Calling all biology-oriented students thinking about where to go to university – here is a post for you!

The Biology Department at the University of St. Thomas is a national leader for undergraduate-led research. We invest a lot in our teaching, but we also are committed to our research with the aim of making an impact on our field (see our recent publications here). Unlike at many larger schools, undergraduate students in our department play leading roles in our research programs. In fact, many of our students present their research at national meetings and co-author papers with their faculty mentors. We strive to create an exceptional environment for students interested in learning how to be the research leaders of tomorrow.

Sustainability is a topic that is getting more attention in our research, our teaching, and our service.  We are excited about continuing the development of this work in the years to come. Our success will depend in large part on the partnerships that we form with students that enter into our program. Below are a few examples of research and teaching projects related to sustainability:

Dr. Jennifer McGuire and her research group investigate issues related to water quality in freshwater environments such as lakes, wetlands and drinking water aquifers. Their interests include chemical fate and transport, applied environmental toxicology, and reactive multi-phase numerical modeling.  One of their current projects is to quantify the rates at which natural processes, primarily bacterial activity, breakdown hydrocarbons from crude oil under various conditions.  Findings from this work help to improve our ability to find cost-effective clean-up strategies for oil spills.

Dr. Kyle Zimmer and his team work on a variety of questions related to the ecology of aquatic systems, with a particular emphasis on Minnesota lakes. The lab has four current projects involving UST students.  The first is assessing the relative impact of watershed features versus fish community composition on ecosystem characteristics in Minnesota shallow lakes. The second is testing the hypothesis that shallow lakes dominated by submerged plants sequester more atmospheric CO₂ than do lakes dominated by algae. The third project is testing for differences in the ecological niches of different types of cisco, an important forage fish in Minnesota threated by climate change and nutrient loading. Lastly, this summer his lab will start a project that will assess how zebra mussels alter the pathway of energy flow and predator-prey dynamics in a Minnesota lake.

Students planting oak trees for the Fish Creek project

Drs. Simon Emms (Biology), Tim Lewis (Biology), and Paul Lorah (Geography) are working on project aimed at both restoring natural habitats and capturing carbon dioxide from the atmosphere to help offset UST’s carbon footprint. The project is restoring oak woodland, savanna, and prairie on river bluffs overlooking the Mississippi River in Maplewood. It is being done in collaboration with Ramsey County, the city of Maplewood, and Great River Greening. It’s being funded by UST’s Campus Sustainability Fund. In 2012, over 200 UST students participated in planting trees as part of courses in the Biology and Geography Departments. The project will also allow current and future generations of students to carry out research on ecological changes that occur on the site as the forest regrows, and to study how different varieties of oak trees perform in the face of ongoing habitat and climate change.

Dr. Dalma Martinovic-Weigelt and her students conduct research on occurrence and effects of endocrine disrupting chemicals and other chemicals of emerging concern (e.g., pharmaceuticals, personal care products) in aquatic environments. The objective of this research is to develop approaches to evaluate whether these chemicals present threats to ecological and human health. Our research has a strong laboratory component and uses technologically advanced approaches (e.g., genomics, bioinformatics) . While we conduct some research in pristine, idyllic settings we are more likely to be found researching urban streams and wastewater. One of our more unappealing field sites is depicted in Upton Sinclair’s The Jungle – a book about the meatpacking plants of the Chicago stockyards.

Scenes from the UST Stewardship Garden

Dr. Adam Kay conducts research with UST students on ecology and sustainable agriculture. Some of his work focuses on the community ecology of ants in tropical rainforests; one part of this work led by UST student Jane Lucas, has examined how ants influence connections between tropical forest canopies and tropical soils. Another part of his lab’s work investigates how environmental phosphorus can influence the ecology and evolution of freshwater snails in New Zealand. Work closer to home combines research on urban agriculture with community service. One of these projects is the UST Stewardship Garden, which combines student-led research on urban agriculture, educational activities, campus outreach, and produce donations to local food shelves. He and current student Taylor Schuweiler are developing the Corner Store Procurement project, which involves testing ecological hypotheses in the UST greenhouse while generating produce for the Minnesota Health and Human Services Corner Store Program.

Dr. Chip Small and his students are conducting research on the fate of nutrient pollution in the St. Louis River Estuary and Lake Superior, combining field measurements, laboratory experiments, satellite imagery, and computer simulations. They are also working on a project in Costa Rica to understand how climate change affects the chemistry and ecology of tropical streams.

One of the products from the Youth Farms service project

UST Biology also has several teaching experiences related to sustainability. Our sophomore level class, The Biology of Sustainability, conducted a service-learning lab to assess soil quality and gardening practices for our community partner, the Youth Farm and Market Project. Youth Farms is a Twin Cities organization that provides experiential education and training activities for over 600 youths organized around the themes of urban agriculture and local food production. UST students collected samples from 13 urban farms in the Youth Farms program and analyzed soil samples for nutrients, heavy metals, and other measures of soil quality. Students then analyzed and summarized the results, and prepared products to disseminate their findings. They produced a variety of products including prezis, web sites, brochures, handouts, and posters. There was even a children’s book and a board game! (see the previous blog post on this event here). It was both productive and really fun.

Dr. Chip Small’s Urban Ecosystem Ecology class explores how cities function as ecosystems.  They are conducting a study for the City of Saint Paul through CityLabs, assessing the feasibility of using community gardens as neighborhood compost sites.  For another project, they have designed a series of experiments involving vermicomposting and aquaponics, using food waste to produce worms, worms to produce tilapia, and fish waste to grow basil. A great video and full blog post about that project is here. They are also involved in an interdisciplinary, collaborative project along with courses in environmental studies, videography, and dance, working with the Ordway Theater and the Pilobulus Dance Company to create an original dance piece exploring how humans interact with the built and natural environments.

UST students after building erosion dams at Mokolodi, Botswana

Dr. Jill Manske’s traveled to Botswana in January. As part of the course, they did a service day at Mokolodi Nature Preserve where they built these dams to help control erosion of top soil during the rainy season. The dams are fashioned from the branches of Acacia trees (which are invasive, so this is also useful in clearing them since they shade out the grasses and low plants) and bunches of grass which were tied into bundles.

Dr. Adam Kay and Tony Lewno’s class, Introduction to Field Ecology, traveled throughout Costa Rica in January 2012. The class focuses on original student-led research projects in remote locations. One place the class visited was a sustainable community in Cerro de la Muerte in the Talamanca range in Costa Rica. For more information about this great experience, see here and here. Note that they’ll be heading back to Cerro and other parts of Costa Rica with a new group of students in 2014.

Students working on a trout farm in Cerro de la Muerte, Costa Rica

All of this work is fueled by student enthusiasm and will. We hope we’ll be able to continue to attract motivated students to help us continue these and other sustainability projects.

For more information, visit our department Facebook page and other posts on this blog.

Kurt Illig

Adolescence can be an awkward time. For humans, the teenage years can be marked by behaviors that are not seen in people of other ages. These behaviors can be relatively benign, such as dressing in all black and going to all-night dance parties, and they can be more dangerous and risky, such as indiscriminate sexual behavior and drug use. Teens usually outgrow most of these behaviors (how many “emo” adults do you see?), but drug use is particularly problematic; research has shown that someone who first uses drugs as an adolescent is far more likely to become chronically addicted than someone who first uses as an adult. Why?

Many scientists have suggested that addiction is the consequence of an over-active “reward” circuit in the brain. Under this view, drug addiction originates as a drive to achieve an outcome that is pleasurable. In support of this view, drugs like cocaine increase the activation of dopamine, a neurotransmitter that is associated with pleasure. But this doesn’t fit every case; for example, why do addicts continue to use drugs even when the outcomes—losing a marriage, a family, a career—are so clearly unpleasant? In fact, drug addicts often report a strong desire to quit using drugs, but find that their behavior is almost automatic, outside their control.

My lab studies the neural circuitry responsible for learning, especially the kind of learning that helps us make connections between an environmental cue and its meaning. Think about that long drive up to the cabin, when you see a big, yellow “M” up ahead. You barely have time to think, “fries and a chocolate shake” before your hands jerk the steering wheel to the right and your car swerves as you make the exit. This link between the sign and its meaning is certainly something that is learned (that is, no one is born knowing McDonalds has fries), but once it is learned the link is automatic; there is no need to think about how the Golden Arches is a sign that stands for McDonalds, that McDonalds is a place to get food, and that the menu includes hamburgers, French fries and chocolate shakes. This form of learning that connects a sign to its meaning is called “associative learning.”

An alternative view of drug addiction is that it is a form of associative learning, where the connections between environmental cues and drug use grow so strong that drug use becomes a compulsive, almost automatic behavior. A smoker lights a cigarette in a particular environment (for instance, in the car) and soon, the environment becomes the reason for the behavior; without thinking, she lights up when she gets in a car. This may be one reason that relapse among former addicts more commonly occurs in familiar environments than in new environments. If this viewpoint holds, then by studying how the brain circuitry responsible for learning changes during adolescence, we should be able to get clues about adolescent drug use, too.

In a paper we published recently in the journal PLoS ONE, we used an odor-guided associative learning task to test whether associative learning changes during adolescence, and we examined gene and protein expression to see whether the dopamine system (which is found in brain areas important for associative learning) changes during this time. We used rats to explore these changes, so that we could look very closely at what was happening in the brain. We used odor associations rather than visual cues because rats get around primarily by using their sense of smell, and they pay careful attention to odors in their environment.

Three undergraduate students were co-authors on the publication: Anna Garske (now pursuing a PhD in neuroscience at the University of Colorado), Chloe Lawyer (a Goldwater Scholar and still working in the lab), and Brittni Peterson (now pursuing a PhD in neuroscience at the University of Minnesota). Six more undergraduates provided help with the two-year project (Kate Hanson, Netsanet Negussie, Rolf Skyberg, Betsy Smith, Anthony Spano and Kim Uy).

We trained rats to dig in a cup of sand to obtain a tasty treat: Froot Loops (rats love Froot Loops). After the rats learned to dig, we put odors in the sand and gave rats a choice between two cups: one cup (e.g., minty sand) contained a Froot Loop, while the other cup (e.g., cinnamon sand) contained nothing. We observed how many trials it would take for the rats to learn the meaning of an odor, which we defined as a rat digging in the Froot Loop cup on eight out of 10 consecutive trials. We tested rats at three different ages: juvenile (21-28 days old), adolescent (34-49 days old) and adult (50-150 days old).

We found that juvenile and adult rats learned the task very quickly; on average, they learned the odor association in about 12 trials. Interestingly, adolescent rats took almost twice as many trials to learn the association (on average, about 22 trials). In addition, we found that adolescent rats had a higher number of trials where they were distracted during the task, either grooming or exploring their cages rather than digging in the cups of sand. Juvenile rats almost never became distracted, and adult rats did so only occasionally. So adolescent rats were not only slower at learning the task, they were also less focused on the task and more distractible. Sound like any adolescent humans you know?

Next, we wanted to find out whether experience with the task would help adolescent animals become faster learners, or at least help them become less distractible. To explore this, we first trained juvenile rats on an odor association task, and then tested them on a new odor association task when they became adolescents. We found that these animals learned the task in about 12 trials, and they also displayed very low levels of distractibility. So previous experience with an associative learning task helped adolescent rats learn faster, and helped them stay focused during the task.

Could the developing dopamine system be playing a role?

Previous research by others has shown that the dopamine pathways that interact with the learning circuitry are starting to mature during adolescence. We were interested whether the cells within the learning circuit were also undergoing changes in how they process dopamine. First, we used real-time quantitative PCR to explore mRNA levels for the dopamine receptor. We found that compared to adult and juvenile brains, there was significantly more mRNA for dopamine receptors in adolescent rats in the areas of the brain that are responsible for associative learning. Second, we used immunohistochemical methods to determine how the dopamine receptor protein was distributed within these areas. We found that the receptors were expressed in about twice as many cells in these brain areas during adolescence compared to juvenile or adult rats. Taking both methods into consideration, we concluded that there are more dopamine receptors in the learning circuitry in adolescent brains than in adult or juvenile brains.

These findings prompted us to test whether targeting the dopamine system with drugs during adolescence would change how well rats could learn the odor association task. We used two drugs that targeted specific dopamine receptor subtypes. When we administered low doses of these drugs to adolescent rats, we found that they learned the associations as fast as adult and juvenile animals, taking about 10 trials to reach criterion. Further, these rats were highly focused during the task, displaying very low levels of distractibility.

These results suggest that dopaminergic modulation of cortical function may be important for learning the meaning of environmental stimuli, and that developmental changes in cortical dopaminergic circuitry may underlie age-related differences in associative learning. These results also suggest that early experience with learning tasks may improve adolescent associative learning.

Our study shows that associations are learned more rapidly, and that behavior becomes more focused, when the dopamine system is more highly activated. Such activation could occur either by a highly rewarding situation or through drug use. What does this mean for drug addiction? It might mean that during adolescence, a drug that is able to activate the dopamine system also activates learning circuitry, which learns behavior of taking drugs, and voilà: an addiction is born.

What could our results be telling us about adolescent behavior in general? What is the advantage of increased distractibility and slower learning during adolescence? Perhaps the system ensures that learning is specific to associations that are repeatedly confirmed, or that are highly rewarding and lead to greater dopamine release. Such a system would be expected to increase behavioral variety and flexibility, including exploratory and risk-taking behaviors. In this way, behaviors that are important for survival such as foraging, colonizing new territory, and engaging in social behaviors are promoted. While these behaviors would increase the survival risk for individuals, the expanded territory and increased social interactions that would result from a population biased towards these behaviors would benefit the survival of the species.

Ecology Gangham style? Well, not quite. But this June UST Biology’s Hangkyo Lim and Tony Lewno will be leading a course that will travel around Korea to learn about the culture and ecology of this biologically diverse area. The course will provide upper-division Biology elective credit. Tuition will be similar to on-campus credit costs. There are only a few slots still available, so contact Hangkyo (lim94497@stthomas.edu) or Tony (awlewno@stthomas.edu) right away if you’re interested. The course is also open to students from other ACTC schools. A full description of the course is below.

BIOL 398: Topics in Ecology and Culture of Korea

Hangkyo at Haeinsa Temple

This course is designed  to help students learn about the biology and culture across the diverse environmental conditions of Korea.  The ecological variety and cultural heritage found on the Korean peninsula are ideally suited to serve the course objectives: 1) the peninsula exhibits a wide range of diverse Northeastern Asian ecosystems, which are not well represented in ecological studies, 2) the Korean peninsula has been populated for longer than 25,000 years and has a well-preserved historical and cultural heritage, and 3) the country is one of the fastest developing countries in Northeast Asia, which provides ample opportunities for studying human impacts on and interactions with ecological systems. Many Korean instructors and their students will support and participate in the program both logistically and intellectually thanks to the connections of the program director.

As an elective Biology course, participating students will learn principles and techniques of Field Ecology under the guidance of Korean instructors and with Korean students.  Students will participate in a field experiment designed to understand the behavioral ecology and conservation of an endangered anuran species.  In another project, the distribution and diversity of the invertebrate and vertebrate fauna will be surveyed and analyzed in the tidal flat zone, brackish water, sandy shallows, and volcanic islands to understand the relationship between the species composition and the diverse oceanic environments.  Students will also study mountain flora to assess the indigenous plant diversity across climatic conditions at varying altitudes.  Each student will have the opportunity to execute the scientific inquiry from making independent hypotheses to data collection and analyses to the result presentation.  Local Korean experts will guide and supervise the activities in the field sites and their students will also collaborate in the entire process.

The Republic of Korea (the southern half of the peninsula, whose approximate coordinates range similarly from northern Georgia to southern Michigan) is situated west of Japan and alongside the northeastern provinces of China (Manchuria).  The country measures approximately 100,000 km² (38,000 mi² ≈ half of Minnesota) and is bordered by the East Sea, the Korea Strait (south), and the Yellow Sea (west). The highly indented coast line (with 4,000 islands) expands 8,640 km (5,400 mi) along the three seas, and the inland water body covers 290 km² (110 mi²).  More than 70% of the peninsula is mountainous (the highest point: 1,950 m, Hallasan Mt.) and contains both deciduous and coniferous forests.  The relatively small area with diverse aquatic and terrestrial ecosystems of the country will provide the students with ample opportunities and field sites to visit and explore.

This abundance of diverse ecosystems and cultural heritage sites can be easily accessible, providing sites rich in opportunities to study and experience the interactions between the environment and human populations of the Northeastern Asian tradition.  The students will meet and actively interact with the local experts and their students affiliated in three different universities, which will facilitate their understandings of the nature and culture under a very safe and friendly circumstance.

The slide show has some of the natural and historic sites the course will visit:

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Phosphorus and the evolution of sexual reproduction 

Mating Potamopyrgus antipodarum snails (photo Bart Zijlstra)

Why do animals reproduce sexually? The answer may seem obvious until you consider that some animal species actually reproduce by making identical clones without input from a partner. Cloning, also referred to as asexual reproduction, has advantages. Most importantly, it results in parents transferring their full complement of genetic information to their offspring; in contrast, sexual parents only transfer half of their genes (the other half comes from the other parent). This advantage is enormous, making it paradoxical that sex is so common in the animal kingdom.

So why is sex so common? Most hypotheses have focused on the benefits of genetic recombination or of producing genetically distinct offspring. One idea – the Red Queen Hypothesis – suggests that sex might be advantageous because it allows parents to produce genetically distinct offspring that are less susceptible to infection by co-evolving parasites. In contrast, asexual groups could have parasites that, over time, evolve specializations that allow them to successfully attack the asexual genotype. The Red Queen Hypothesis has received considerable support. However, it’s unlikely that parasites are the only ecological factor favoring sexual reproduction, and the extent to which other factors influence the success of sexual reproduction is poorly understood.

In our recently published paper in the journal Heredity, my collaborators Dr. Maurine Neiman (from the University of Iowa),  Dr. Amy Krist (from the University of Wyoming), and I develop a new hypothesis about how the availability of food resources could influence the success of sexual reproduction. Our focus is on the role of phosphorus in food and in organisms themselves. We start with the fact that most asexual animals tend to have higher ploidy (=# of chromosome sets) than closely related sexual groups. For example, the New Zealand freshwater snail Potamopyrgus antipodarum consists of both diploid sexual individuals and asexual individuals that are either triploid or tetraploid. The key part of our argument is that higher ploidy should generally increase an individual’s sensitivity to scarcity of dietary phosphorus. The reason for this is that, all else being equal, higher ploidy individuals should have more nucleic acids (DNA and RNA) in their bodies than do individuals with lower ploidy. Because nucleic acids contain more phosphorus (about 9% by dry mass) than other major biomolecules and can make up a substantial fraction of an animal’s body mass, higher ploidy animals will generally contain more phosphorus. We argue that this higher phosphorus content should increase demand for dietary phosphorus and in turn make organisms more vulnerable to phosphorus scarcity in the environment. In our paper, we explain how environmental phosphorus availability should influence competitive interactions between sexual and asexual groups that differ in ploidy. Finally, we discuss whether our hypothesis is consistent with some well-documented patterns of where sexual and asexual groups are found.

Hopefully our paper will be a step toward a more comprehensive understanding about how environmental factors explain why sex is so common in animals.

A sign on a building in downtown Christchurch

At first glance, Christchurch looks like a war zone. We’ve spent several days here this January (for our project on the ecology of sexual reproduction in a freshwater snail), and we’ve seen shocking evidence of the major earthquakes of 2010 and 2011. There are ruined buildings, piles of rubble, and empty lots throughout the downtown. It’s so different from the quaint city Adam remembers from 2007 when he was here for a conference with UST student Katie Theisen and her sister Becky. However, as we’ve walked around we’ve found so many imaginative recovery projects being developed around the damage. What’s particularly interesting to us about these projects is that they share many features with ecological sustainability efforts happening elsewhere.

Katie and Becky Theisen in downtown Christchurch in 2007

City Center was quaint in 2007

The Christchurch Cathedral, 2007

Christchurch experienced a series of earthquakes and aftershocks in 2010 and 2011. In early September, 2010, a 7.1 magnitude quake struck near Christchurch. Although it did not result in any deaths, it likely significantly weakened many buildings and other infrastructure. Then, on February 22, 2011, a 6.3-magnitude quake struck with an epicenter just south of Christchurch. Many buildings collapsed as a result of the quake, including the steeple of the cathedral in Christchurch’s main square. The quake killed 185 people, almost all in the downtown area.

Nearly two years later, the city is still largely in ruins. Many buildings and houses are condemned but not yet demolished. We’ve heard that residents are battling with insurance companies to get fair compensation for their property. Hotel managers have told us that tourists aren’t staying in downtown Christchurch because of fears of aftershocks. In general, we’ve felt that people are frustrated and tired. The rebuilding of the downtown will take many years, and it’s easy to see how people could be discouraged and overwhelmed by the challenge.

The Christchurch Cathedral January 2013

Along the Avon river

A store interior

A bridge across the Avon

A condemned complex

The abandoned convention center

Scenes like this are everywhere

Very few buildings downtown remain intact

But also instead of discouragement we’ve felt amazing energy and excitement about the rebuilding efforts. It seems like one main goal is to quickly make an interesting environment that can attract visitors. One regeneration organization group is called Gap Filler, a collection of projects designed to fill vacant sites for short periods. The projects we’ve seen are very artsy and cool. One of our favorites is the Palette Pavilion, a meeting space in the middle of a big vacant lot downtown. Blue palettes are stacked to make 10-ft-high walls enclosing a central space with a performance stage and a seating area. The palettes are covered with native plants and various art pieces. Other gap fillers were Dance-O-Mat – a dance floor on a vacant site with coin operated lighting and sound, Gap Golf – a temporary miniature golf course, and numerous murals and other art projects.

Outside the Pallet Pavillion

Liz Chambers inside the Pavillion

Part of the seating area inside the Pavillion

Probably the most substantial regeneration effort is the container mall called Re:START. The mall is made up of brightly painted shipping containers recommissioned as retail stores, restaurants, and coffee shops. The tenants include major retailers and downtown businesses that were destroyed by the quakes. Containers house other businesses nearby, including this interesting bar that uses old chests and refashioned shopping carts as tables and chairs. Another interesting reconfiguration is the Smash Palace restaurant that has built a kitchen, bar, and seating into old city buses on an empty lot.

Some of the bright colors in the container mall

Hummingbird Coffee in the container mall

Native plant landscaping in the container mall

Another view of the container mall

Adam at the Smash Palace restaurant

Liz and Adam at the Revival Bar

Inside the Revival Bar

Creative landscaping in a vacant lot

Food trucks are common

Overall, there is a strong emphasis on recycling materials to make interesting public spaces. The structures are simple, but the designs are creative and the overall feel is hip and vibrant. I wonder if this could be a model for a lower energy society in other parts of the world.

During our field sampling in New Zealand this January, we’ve found that it’s easy to get excited about all of the beautiful landscapes and striking plants and animals. However, the more we learn about New Zealand ecology, the more we realize that we have to have a nuanced emotional response to what we see. New Zealand has many invasive species, many of which do substantial damage to native ecosystems. It turns out that much of the biology that catches our attention only exists in New Zealand because of recent introductions resulting from human activities.

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One funny experience happened on our first day sampling. We were walking from sampling Lake Rotoroa near the north end of New Zealand’s South Island. We stopped to admire some beautiful pink flowers and Liz said “Oh, cool” and snapped a picture. Maurine Neiman, our collaborator from the University of Iowa who has worked for over a decade on New Zealand snails and the evolution of sexual reproduction, replied with a tender smile, “Oh, those are actually invasive, haha”. Liz went silent and Adam chuckled. It turns out that the plant with the pretty pink flowers, Digitalis purpurea (=foxglove), was introduced to New Zealand by European settlers some time before 1860.

Like other islands, New Zealand is vulnerable to invasive species. Islands tend to have lower biological diversity than continental areas, in part because they’re distant from populations of potential colonizing species. New Zealand has been isolated from other land masses for about 80 million years. On the one hand, this isolation has produced distinctive and interesting species. For example, there is a large cricket-like creature, the weta, that fills the ecological niche of mice (New Zealand is known as “a land without teeth”, because there are no native land mammals – Adam and I thought this matched the countries overall cute persona!). On the other hand, the isolation likely has also resulted in the evolution of species that are susceptible to competition or predation from continental species that have traits honed by a long history of ecological challenge in a biodiverse environment.

One well-known example of vulnerability involves the flightless birds of New Zealand. Several species of New Zealand birds (including the weka (short video) and of course the kiwi), likely evolved flightlessness because they didn’t face predation pressure from land mammals. However, the introduction of many land mammals since European colonization has resulted in widespread population declines for these flightless birds. The kiwi, the iconic and lovable symbol of New Zealand, is particularly vulnerable to predation by possums and stoats (a member of the weasel family), which are possibly the most despised pests among the people of New Zealand. (According to the New Zealand Department of Conservation, 9 out of 10 north island kiwi chicks born in the wild will die before they are a year old. However, conservation efforts in kiwi sanctuaries all over the country have increased survival rates of kiwi to nearly 70%!)

Liz with her possum purchases

We’ve already experienced the frustration of New Zealanders with the scourge of invasive species. One example was when we were in Hokitika on the west coast. We stopped at ‘The Possum People’, an interesting store that specializes on vests, hats, shoes or other odds and ends made with pelts from possums that were hunted or trapped as part of eradication efforts.  While we were perusing the selection of giant awesome possum vests some native New Zealanders came in and one of the women asked how many ‘pests’ it took to make a blanket hanging on the wall behind the register. The cashier replied, “About 40”, and a chorus of four women responded “Good!” and the room erupted with lighthearted laughter. The people here are happy to see them go, and it’s amazing how they are able to make a new market out of the pelts.

A stunning landscape near Arthur’s Pass filled with beautiful but invasive purple lupines

Because we’ve learned that there are so many invasive species are so common in New Zealand (e.g., 42% of bird species are non-native!), we now end up analyzing vistas as we take pictures and videos. While driving through Arthur’s Pass (a 2000m pass in the center of the south island) we entered a beautiful valley surrounded by snow-caped mountains and filled with vibrant blue tide pools sprinkled with a sea of purple plants. Adam thought the plants looked like the purple lupines in Minnesota grasslands. We left hoping that this beautiful landscape was a result of convergent evolution in nitrogen limited soil (because purple lupines are nitrogen fixers) and that New Zealand was part of its native distribution. It turns out that the purple flower is Lupinus polyphyllus, a plant first documented as naturalized in New Zealand in 1958. According to Wikipedia, it may have been introduced by tour bus drivers interested in adding color to the landscape. Today it threatens native plants near river beds in the South Island.

One obvious landscape transformation related to invasive species has been the conversion of natural rainforest into pasture lands for sheep and cows. In 1773 and 1777, sheep were brought to New Zealand by James Cook (the first person to circumnavigate New Zealand). Cook gave sheep as a gift to the Maori, the native people of New Zealand. However, it wasn’t until the establishment of substantial European settlements (~1840) that sheep farming spread throughout the island. Since that time, sheep have been an integral part of the New Zealand economy. Although sheep numbers have declined over the last two decades there are still many more sheep (40 million) than people (4 million) in New Zealand (here is a nice video of a common sight). Sheep are everywhere we’ve been, and they are not to be messed with (as Liz learns here).

New Zealand will continue to be plagued by invasive species, but further spread can be curtailed using public awareness campaigns. One invasive species relevant to our work is Didymosphenia geminata or Didymo, which has been given the charming little nickname of “rock snot”. It is a diatom that covers rocks on the bottom of rivers and lakes in long stringy mats. It changes water quality and alters lake habitats, which in turn harms native invertebrates and fish species. Didymo has spread over the South Island since the first reported sighting in 2004. It can be spread by just one drop of water, so we clean all our equipment in 5% detergent between sites. Luckily we haven’t seen rock snot in any of the lakes we’ve sampled, although we’ve read that it’s been found in many rivers and lakes in the South Island.

Fighting Didymo spread with flair

a common warning at all of our sampling areas

Ironically, our study species Potamopyrgus antipodarum is one of the few native New Zealand species that is actually invasive in other parts of the world. A recent article in The New Zealand Herald declared that this tiny mud snail is taking over the world! It’s now found in Europe Australia, America and Asia. Although it’s not entirely clear why it is a successful invader, it may be due to the fact that it can live outside its natural aquatic habitat for long periods of time, it is very small (about the size of a pencil lead!), and some members can reproduce asexually (which means that even a single snail can make a lot of offspring quickly). Maurine has had a few conversations with New Zealanders who have expressed surprise and maybe even some pride when they hear that a native species is invasive somewhere else. It must be emotionally draining to live in such an ecologically fragile country.

Field ecologists need to be adaptable, patient, and persistent. We often work in remote locations under variable conditions with limited resources. These limitations certainly make things more difficult, but it’s also really fun to figure out ways to get around the constraints and unexpected challenges that come our way.

Whitebait can solve most problems. It’s a fried pancake filled with fish fry (those white worm-like things)

This January, UST Biology major Liz Chambers and I (along with our colleagues Maurine Neiman from the University of Iowa and Amy Krist from the University of Wyoming) are measuring ecological characteristics of various lakes on the south island of New Zealand. Our funding for the project comes from a grant from the National Geographic Society (to Maurine). Our main goal is to test our hypothesis about the relationship between environmental phosphorus limitation and the relative success of sexual and asexual forms of the freshwater snail, Potamopyrgus antipodarum (for more information about the project, see here). Toward this end, we’re sampling 15 lakes across the south island to estimate the extent of nutrient limitation for algae (the main food for our snails) and to determine algae chemical composition. We’re also collecting snails for various biochemical analyses that will help us estimate the extent to which their growth is limited by phosphorus availability.

One challenge for us is that New Zealand is sparsely populated and the lakes we’re sampling are in fairly remote locations. It isn’t possible for us to return our samples to a lab for processing. As a result, Maurine and Amy worked out a system for taking care of samples in whatever motel room we find ourselves in. In the afternoons and evenings, we’ll be out on the porch scrubbing tiles with toothbrushes and filtering water samples. We also have a cute little toaster oven that dries our samples. And you’ll often find Liz back in some dark corner running chlorophyll A assays on our portable spectrophotometer. (Liz would like to point out that the room NEEDS to be dark, and she is not emo or anti-social.)

Maurine setting up NDS assays in the available space!

our toaster oven is drying samples

thankfully no noxious chemicals on the kitchen counter

Maurine and Bennett processing samples

Amy Krist collecting algae in the kitchen

Another challenge is that we don’t have a lot of money or time to do this project. It’s really expensive to fly to New Zealand, and the cost of living here is also high (e.g., we’re currently paying $10/day for internet). Maurine and Amy did a fantastic job organizing the field sampling, but the equipment all had to be sent from the US because we didn’t have time to buy and build things once we arrived. We also didn’t have the opportunity to scout out our sampling locations before we got here. So we had to be creative. Maurine and Amy spent the first 3 weeks of December traveling to the lakes to lay out white tiles (to assess algal growth) and to put down Nutrient Diffusing Substrate (NDS) assays (collections of glass filters spiked with different nutrient mixtures – these assays allow us to estimate which nutrients limit algal growth under standardized conditions). Now, three weeks later, our job is to go back to the lakes, find and retrieve tiles and NDS assays, collect snails, and prepare samples for analysis.

That sounds easy enough, but the weather has changed lake conditions dramatically over the last few weeks. Heavy deluges resulted in water levels in our lakes to increase but as much as 2 meters. Our best experience was at Lake Ianthe, where we expected to collect our tiles and NDS assays in about thigh-high water. When Liz and I got to the site, we realized that the shore line was gone. We began walking out to the sample location in our waders, but the water got deep quickly and our waders soon filled with water. We tried to swim in our waders (not a good idea). We then swam out to the sample location in our clothes, but we couldn’t find them in the murky water. (Here is what we looked like when we made it back to shore). Later in the afternoon, we returned with Maurine and her husband Bennett. We created a floating platform (made out of an inner tube, duct tape, and a cafeteria tray) to bring our tiles and NDS assays to shore (Here is a video of Adam being a wimp as Maurine launches into the cold water) (Here is a funny video of Liz, Adam, and Maurine swimming to the site ). Using swimming goggles and with a little luck, we were able to find all but one of our samples. It was exhilarating!

After a drive across the south island over Arthur’s Pass, we’re back in Christchurch to drop Bennett at the airport. From here, it’s down the southeast coast and then over to Fjordland in the southwest. Spirits are high.

Adam near Arthur’s pass

Liz near Arthur’s pass

Why have sex? It’s a difficult question to ask without sounding creepy. But the answer isn’t as obvious as you might think.

A male trying to offset the two-fold cost of sex

Evolutionary biologists have shown that sexually reproducing organisms should theoretically be at a disadvantage when competing with asexual organisms. The reason for this is that sexual females need male partners to reproduce, whereas asexuals can reproduce by themselves (“who needs guys anyway?” says Liz). Therefore, all else being equal, sexual females (which produce both males and females) will produce only half as many descendants over the long term as asexuals will. The production of males is referred to as the “two-fold cost of sexual reproduction”, and it should result in sexual forms being outcompeted by asexual forms. However, sexual reproduction is very common, especially in animals. Why sex remains so common despite this two-fold cost has been termed the “queen of questions” in evolutionary biology.

Research on this topic has focused on finding advantages of sexual reproduction that can more than offset the cost of producing males by sexual females. One clear advantage is related to the ability of sexual organisms to produce genetically distinct offspring instead of identical clones of themselves. One reason it can be good to have offspring that differ genetically from yourself is if you’re attacked by parasites that can adapt to your particular genetic makeup. This idea is referred to the Red Queen Hypothesis (the Through the Looking Glass character said “It takes all the running you can do, to keep in the same place.” The analogy to evolutionary biology is that populations need to evolve in order to remain equally successful in the face of challenge from parasites or other environmental challenges that are themselves evolving). Although this idea has received a lot of support, it’s not well understood how other features of the environment can affect the benefits of being sexual.

The star of the show, Potamopyrgus antipodarum

This month, UST junior Liz Chambers, Adam Kay, and our collaborators (Maurine Neiman from the University of Iowa and Amy Krist from the University of Wyoming) are testing a hypothesis about how the availability of phosphorus in the environment could affect the advantages of sex. Fortunately for our adventurous selves, our study system is a freshwater snail species, Potamopyrgus antipodarum, that occurs in New Zealand. It is a rare species of animals that has co-occurring sexual and asexual individuals. These snails are found in lakes across New Zealand, and different lakes have different mixtures of asexuals and sexuals. It has become a model system for studying what determines the relative success of these different reproductive strategies.

Our hypothesis focuses on a common difference between sexual and asexual taxa – their ploidy level (that is, the number of chromosome sets per cell). In our snails, sexuals have 2 sets of chromosomes (they’re diploid) while asexuals have 3 or 4 chromosome sets (triploids or tetraploids).  Our hypothesis is that higher ploidy increases demands for dietary phosphorus (P), which is an important component of nucleic acids. Our prediction is that the growth and reproduction of organisms with higher ploidy (that is, asexuals) will be more sensitive to scarcity of phosphorus in their food. If that’s the case, it would indicate that phosphorus scarcity in the environment would be more detrimental to asexuals than to sexuals. In short, sexuals snails may do relatively well in low phosphorus conditions because their lower nucleic acid content and in turn their lower demand for dietary phosphorus. This finding would be important because it would indicate that the success of sexual animals could depend on the phosphorus content of the foods in their environment.

Maurine has stepped to the side. Not sure why…

where did Liz go to now?

Pretty

Feeling ewe-y after a long drive on a windy road

“Should we be leading? Liz?”

“Those sheep are not RAMbunctious” – Liz

Our work this January aims to determine whether there is the potential for snails in our system to experience phosphorus limitation. We are traveling to 15 lakes across the south island to measure various indicators of phosphorus availability for our snails. The field work is pretty straightforward – we’ll have more posts about it soon (here’s a video of Liz and Lady Lake). So far, we’ve traveled up the northeast coast and across the northern part of the south Island (does that make sense?). (Here’s a video of the view from Kaikoura). I think we’ll be able to post several more times about our adventures exploring the sex life of snails over the next few weeks. Liz thinks this ends abruptly, but there’ll be more to come later…

Below are posts from UST Biology’s Kerri Carlson and one of her students, Ryan Augustin. They are reflections on a departmental seminar from this semester given by David Largaespada from the University of Minnesota Cancer Center.

Dr. Carslon’s reflections

It has always amazed me how scientists are able to harness the power of naturally occurring phenomenon to develop novel tools to enhance our understanding of genetics.   The use of plasmids and restriction enzymes revolutionized the way we study genes through the advent of gene cloning.  An understanding of homologous recombination led to gene knock out technologies in mice.  In Dr. Largespada’s seminar we were presented with another example: the use of a transposon system called Sleeping Beauty to identify novel cancer genes.  (Transposons are DNA elements that are capable of “jumping” from one DNA location to another DNA location in the cell of an organism-and in some cases cause mutations).

Most of us have likely felt the impact of cancer in our lives. Cancer is a genetic disease and historically, forward genetic screens (in which a researcher causes mutations in a mouse, looks for tumor development and then works to identify the gene mutations that led to that tumor) have moved slowly. This is because forward genetic approaches are long, labor-intensive tasks.  As a geneticist who has been involved in these types of studies (although with heart disease not cancer) I can speak from personal experience that this can be painful and frustrating! The Sleeping Beauty System for causing mutations has made the process of identifying cancer genes significantly quicker and more efficient.  In addition, each cancer type is characterized by a unique group of important genes.  The Sleeping Beauty system has allowed researchers to generate genetic profiles for many cancer types (including cancers that have previously been recalcitrant to studies in mouse models). While there is still a lot of labor and cost involved in using this tool, the advantages over past approaches are significant.  After listening and talking to Dr. Largespada, I can’ t help but feel hopeful that his efforts will one day soon lead to new patient specific therapies for cancer.

While not the focus of his talk, Dr. Largespada also touched upon the use of the Sleeping Beauty Transposon system for gene therapy.  Gene therapy involves correcting defective genes that cause genetic diseases.  As a human geneticist I have interacted with many people that suffer from debilitating genetic diseases, and I have been hearing about the potential of gene therapy for many years.  Sadly success in this field has been a long time coming and many initially enthusiastic researchers have been disheartened.   There are many factors that have prevented progress in this field.  For example many gene therapy researchers rely on viruses to deliver genetic material to patient’s cells.  These approaches are hampered by the risks of immune responses from the patients, a size limit in the DNA material that can be delivered, and concerns that the inactive virus will become active and cause disease.  The Sleeping Beauty system, while not without risks of its own, overcomes many of the concerns that exist with viral gene delivery systems.  After the seminar Dr. Largespada mentioned that (although not yet published) the first human gene therapy trial with a Sleeping Beauty system has shown some success!  This intrigued me.   I am looking forward to reading the published results.

Overall, I left Dr. Largespada’s seminar with a sense of amazement over the progress they have made in only a few short years towards understanding the genetics of different cancers, an appreciation for the power of the Sleeping Beauty Transposon System as a genetic tool, and curiosity (and perhaps cautious optimism) to see how Sleeping Beauty will fit into the gene therapy field.

Mr. Augustin’s reflections

Sleeping Beauty is not often linked with mice, genes, and cancer; but Dr. Laragaespada’s seminar revealed a new approach regarding forward genetics that takes advantage of a specific transposable element called Sleeping Beauty (SB). While some of his talk was beyond my level of understanding, many of the techniques and issues that were brought up provided unique insight into the topics discussed in our St. Thomas genetics course—including forward genetic screens using random mutagenesis, the creation of transgenic mice using deletion vectors and homologous recombination, the identification and amplification of mutated genes using PCR, the quantitative study of gene expression using RT-PCR, and the important use of bioinformatics for studying unknown nucleotide or amino acid sequences and their relation to entire genomic systems.

In his talk, Dr. Laragaespada introduced us to the “old” approach of studying mutations linked to cancer—randomly mutating mice DNA in order to induce tumor growth and subsequently working to find the causative mutation—but he pointed out the difficulty in this approach since the genomes of mice and humans are naturally polymorphic, displaying thousands of dissimilar sequences. When specifically studying cancer, the causative mutation may not be easily detected. Ironically, the “new” approach for studying genetic mutations—using whole genome sequences and bioinformatics software—still leads to the same problem. Even though scientists are realistically capable of attaining entire genomic sequences of cancer patients (or test organisms), the specific mutation linked to oncogenesis is difficult to pinpoint.

For these reasons, Dr. Laragaespada’s research team is taking advantage of a technology that has its roots in the naturally occurring genomes of almost every organism—transposons. Transposons are genetic elements that literally “hop” around the genome, cutting and pasting themselves to and from different sequences. Currently, specific roles for these elements are not known; however, some geneticists are manipulating this random “cut and paste” mechanism to study cancer—specifically cancer linked to mutations that can be mimicked through transposon insertion.

Sleeping Beauty is one of these manipulated, synthetic transposon elements that has been useful for three reasons: it has provided an all purpose mutagenesis system in mouse somatic cells, it is able to locate both oncogenes and tumor suppressor genes, and it can work for most types of cancer. The beauty of this system (no pun intended) is that the transposon’s inherent ability to mutate cancer causing genes can now be linked to an actual location within the mouse genome. Using PCR, the junction between the Sleeping Beauty transposon and genomic DNA can be amplified and identified from tumor cells of mice. A question remains, though, as to how this insertional mutation can be linked to cancer formation. Laragaespada’s lab obtains hundreds of thousands of these amplified sequences and looks for repeatable patterns from mice possessing similar cancers. Using this method, his research team can identify 60-70 “cancer genes” for every 100 tumors analyzed—which, in my opinion, is an amazing feat.

Laragaespada has implemented a tissue specific, insertional mutagenic system for studying cancer causing genes in mice; but this feat still begs the question: Is any of this relevant towards the study of human cancer? Even after acknowledging the present benefits of sequencing technology and the important link between epigenetics and cancer, our speaker provided much hope for the relevance of transposon technology towards the study of human cancer. First, sequencing technology cannot detect subtle promoter differences or rare subsets of human cancers that are evident with Sleeping Beauty. Second, by using mice for these studies, correlations may be discovered between mutated genes and the phenotypes of certain tumors. And finally, this transposon system has provided a large number of candidate genes with known mutations causing either a gain or loss function—important implications for the study of cancer formation.

Is Sleeping Beauty a perfect model for studying human cancer? No. Does it provide valuable information and a promising future? Absolutely. By comparing Laragaespada’s mouse model (along with the list of cancer-linked insertion sites) to the accumulating data from human cancers, future research hopes to find recurrent and causative links between mutations and human oncogenesis. From here, functional assays (e.g. knock-out studies, TALEN technology, and other approaches studied in our genetics course) will hopefully narrow down the most important cancer-causing genes, and also help identify therapeutic steps to help treat and manage mankind’s most elusive disease.

Students in Dr. Jill Manske‘s class (BIOL 467- Emerging Infectious Diseases) completed a semester-long project on dual use research (life sciences research that yields information with the potential to be misused to threaten public health or national security) and the case of influenza A virus subtype H5N1. As part of  the project, the class wrote an informal opinion piece. Here it is!

Pandemic in the Periphery:

How Dangerous the Search for a Cure Could Be

Edward Aika, Daisy Alfaro, Erica Bye, Terese Heighway, Abby House, Ashton Johnson, Brandilyn Reak, Toni Teague, Linda Thomas, Paul Zerfas

21 December, 2012

Department of Biology, University of St. Thomas

Introduction to Influenza: The Common Misconception of the Common “Flu”
Through modern advancements in both science and technology, researchers have been able to stand toe-to-toe with some of the world’s deadliest infectious diseases. Like a zookeeper walking into the lion exhibit, we have developed a sense of invincibility while handling these diseases. We must be careful though. There is always that one rare occasion when the zookeeper pays with his life by encountering nature too closely. High-risk agents and toxins are no different. By playing God in the laboratory, we often forget that we are handling nature. Whether through ignorance or intention, there exists an ever-present possibility that our creative capacity exceeds our foresight. Unfortunately, discussion and action are already too late. Toying and experimentation with these high-risk agents have been done and sent for publishing. More work is in progress. But, with what, you may be asking? This work does not involve work with history’s notably notorious killers, like smallpox or the plague. It involves a virus that the body’s defenses normally fight off. It often gets mislabeled as several common symptoms of other illnesses. It involves the virus that everyone loves to shrug off as no big deal: INFLUENZA. And now, we have a bigger problem on our plate than we ever imagined.

According to the CDC, seasonal influenza infects the respiratory tract of roughly 5-20% of the U.S. population.¹ Vaccines and antivirals help prevent complications and severe infection, allowing for us to sleep at night. More often than not, those infected are down for a week but return even more resilience to the flu without a second thought. However, very few laymen know the potential behind the flu’s biology. More specifically, the strain of influenza that has come to be known as the “the bird flu”, H5N1, packs more punch than otherwise known. The World Health Organization has reported an unfathomable mortality rate of 60% for those infected with highly pathogenic avian influenza H5N1 (HPAI H5N1).² Fortunately, we can breathe at least one sigh of relief. Thanks to differing receptors on our cell surfaces, HPAI H5N1 is unable to sustain human-to-human transmission, and infection is reserved for those who intimately handle infected birds. But we can’t celebrate just yet. Mother Nature always finds a way to “one-up” us. One weapon in her arsenal is the capability for genetic recombination. We all remember the 2009 H1N1 influenza pandemic as being globally widespread. In terms of its virulence, however, its bark was worse than its bite. However, let’s say, for instance, that only one little cell is introduced to both the H1N1 strain and the H5N1 strain. Let’s expand that further and suppose that the two strains decide to do a genetic tango. A switch and a swap, and voilà: now, we have a new virus with swine flu’s bark and bird flu’s bite. Now that bigger deal just became a scary reality. However, you might be convincing yourself, “Mother Nature takes her time! We’ll be fine.” To that, two men named Ron Fouchier and Yoshihiro Kawaoka would say, “Are you so sure about that?”

“And then the first ferret sneezed…”: How Ron Fouchier and Yoshihiro Kawaoka Amplified the Concern

Ron Fouchier and Yoshihiro Kawaoka demonstrated just how scary H5N1 can be when they independently conducted research with this menacing virus and tried to get their papers published. However, it was not so simple to share with the world what they had created. Both papers were labeled as “dual use research of concern” or DURC. This means that the risks associated with their work could potentially outweigh the benefits. In other words, the research was super super super dangerous despite the potential of obtaining ground-breaking results. This term, DURC, may not be one that many people in the scientific community are familiar with. Even experts disagree on what defines DURC and how the Fouchier and Kawaoka papers should be published. Therefore, we first need to understand what makes these experiments unique as well as why scientists were so concerned with releasing this information.

Fouchier himself stated that the mutated H5N1 virus is “probably one of the most dangerous viruses you can make”…one of the MOST DANGEROUS viruses you can make. When Fouchier “mutated the hell out of H5N1”, it eventually became airborne transmissible between ferrets. “This is very bad news, indeed,” stated Fouchier. Great. Furthermore, his findings suggest that this mutated H5N1 virus may also be airborne transmissible between other mammals. And yes, we are other mammals. This wouldn’t be such bad news if the virus had required an extensive amount of mutations. But the fact that Kawaoka and Fouchier were able to transmit the virus literally through sneezing ferrets with as little as four or five mutations means that evolution may outsmart us more quickly than we originally thought possible.

This may be especially true considering this research on HPAI H5N1 has come to a screeching halt. What was initially a 60-day voluntary moratorium agreed upon by influenza researchers including Fouchier and Kawaoka, has been dragged out for almost a year. So as Fouchier and Kawaoka’s mutated H5N1 viruses sit untouched in the research facilities, H5N1 may be growing wings in the wild.

The Double Edged Sword of Dual Use Research of Concern

An organic chemistry final could go without a hitch, provided you’ve taken the time to study endlessly in the Leather Room, attend all review sessions, and even bring out your artistic side in crafting a rather colorful set of study guides. OR, the final could end in an incredible failure because of one freakishly simple aspect: you forgot to set an alarm and slept through the exam. This is DURC.

Dual use research of concern is research that could potentially be used to cause widespread harm to the general public. DURC does not exist simply because it is guaranteed to lead to an adverse outcome (i.e. the Viral Villain walks out of the lab with a vial of mutated H5N1 and single-handedly launches a pandemic). However, DURC exists because of the possibility of the research to be used to do harm. This is one side of the double-edged sword.

On the other “edge”, DURC may still lead to groundbreaking results. Kawaoka and Fouchier are essentially trying to predict evolution. The thought is that if we can get a few steps ahead of evolution, we may be able to detect extremely dangerous H5N1 strains in the wild and respond to them. How would we respond? By having a specifically tailored vaccine and/or treatment ready for use. In this case, dual use research of concern could be incredibly beneficial.

However, we need to remind ourselves that these potential benefits, such as a fantastic H5N1 vaccine, do not “solve” the risks that are still involved. It is still entirely possible that the Viral Villain could launch his pandemic. Therefore, we need to analyze this double-edged sword. In the hands of science, which side of the sword will come swinging down to land on the chicken’s head? Hopefully, we all agree. After all, we’d still like to pass our organic chemistry final.

Education: The Intellectual Vaccine to This Potential Danger
            So what does any of this information about DURC’s “double-edged sword” mean to the average college student? Well, in short, it means a lot. We feel that one of the greatest tools available to both the scientific community and the general public in combating the dangers of conducting DURC is to educate those who are about to enter into the field, such as us science nerds.

The first step is to realize that DURC even exists. From this point, educational materials, such as instructional yet entertaining YouTube videos, should be used to further inform students. Rather than conducting classes in which massive amounts of material are memorized and later dumped onto a final exam, students should be encouraged to view research through a different lens. Students should be able to recognize the benefits AND the risks of a research project and how this could impact both science and the general public. By maintaining this mindset throughout our undergraduate research careers, we will be able to move into our future careers with a broader sense of understanding and preparedness toward DURC. Long story short: we need to avoid scientific tunnel vision.

So here’s the point: the goal is to start with small steps. We need to inform. We need to educate. We need to practice. With these humble beginnings, we will develop a greater awareness of just how important it is to understand our responsibility to perform safe yet pivotal research. Let’s do this. Challenge yourself. Change our world.

 More detailed information about this issue as well as access to the report is available upon request. 

Dr. Dalma Martinovic-Weigelt and friends sampling from the Bahai farm in Minneapolis

The Biology Department at the University of St. Thomas is committed to integrating research, teaching, and community outreach activities. On Friday December 14 (2012), our new sophomore-level class (Biology 209 – Biology of Sustainability) had a symposium to display student projects from a service-learning lab on sustainable agriculture. The lab was designed to assess soil quality and gardening practices for our community partner, the Youth Farm and Market Project. Youth Farms is a Twin Cities organization that provides experiential education and training activities for over 600 youths organized around the themes of urban agriculture and local food production (youth farm link). Our UST students collected samples from 13 urban farms in the Youth Farms program and analyzed soil samples for nutrients, heavy metals, and other measures of soil quality. Students then analyzed and summarized the results, and prepared products to disseminate their findings. They were allowed to choose among three target audiences: farm managers, youths involved in the program, or the UST community. Student groups produced a variety of products including prezis, web sites, brochures, handouts, and posters. There was even a children’s book and a board game! We awarded prizes for best offerings in each of the categories.  It was a hard choice because there were so many good ones. Here are the winners:

“Decreasing Environmental Impact” – a brochure by Liz Chambers, Christian Hager, Dalton Neu, and Aly Phillips.

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“Youth Farms Project: Nellie Stone” – a website developed by Natalie Khoury and Eyerusalem Lemma

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“FARM” – a board game by Jill Haugen, CeCe Peterson, and Lexi Tarter

The FARM game with Lexi Tarter and CeCe Peterson

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“A Kid’s Guide to Urban Farming” – a children’s book by Megan Beetch, Abby Lown, Allison Keith, and Tess King

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“Services for Urban Gardening and the Youth Development Program” – a Prezi by Meaghan Hunt, Lauren Knapp, Meghan O’Reilly, Devin Molnau

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UST Biology’s Chip Small and colleagues recently published a study in Limnology & Oceanography, a leading ecosystem science journal. Below is a general audience description. The full article is available here.

Chip Small on Lake Superior

Gazing out across Lake Superior from a rocky beach on Minnesota’s north shore, it’s easy to imagine that this massive lake has been unaffected by humans.  The crystal-clear waters of this lake, which holds 10% of Earth’s liquid freshwater, hide the fact that, over the past century, nitrate levels have increased more than five-fold.  Scientists have assumed that this increase is simply due to external inputs such as nitrogen deposition from the atmosphere.  However, a new study published in the journal Limnology & Oceanography, my colleagues and I show that a group of microbes that was only recently discovered is playing an essential role in maintaining an imbalanced nitrogen cycle.

The process of nitrification is an essential link in the nitrogen cycle, in which a waste product (ammonia) from fish and zooplankton is converted into nitrate by a specialized group of microorganisms.  In order to understand how this process works in Lake Superior, our research team conducted experiments in a series of research cruises from 2009-2011. We added isotopically-labeled nitrogen to bottles of lake water from 10 different depths spanning the 150 m deep lake, and attached these bottles to cages on a long floating cable.  A day later, we retrieved the bottles, and measured how much of the labeled nitrogen had been transformed from ammonia to nitrate.

The actual rates we measured in and of themselves were not particularly exciting–similar to values measured in coastal ocean waters, and much lower than most other freshwater lakes.  But when we put our data together with the other pieces of this nitrogen puzzle, we found that nitrate is being produced by nitrification at a rate more than 50 times greater than external nitrogen inputs, and also at a rate much greater than it is being removed by other biological processes.

Until a few years ago, scientists believed that only a handful of bacterial species were responsible for transforming ammonia into nitrate.  Recently, a group of archaea (first described from samples collected at a wastewater treatment plant!) have been shown to be the dominant group of nitrifiers in the ocean, and our colleagues at Bowling Green State University showed that this same group of archaea are also responsible for nitrification in Lake Superior (the nitrifying bacteria that you would find in a textbook are not present).  We found that these nitrifying archae were absent from the shallow depths of the lake during the summer months, which temporarily shuts down the nitrogen cycle, until the water mixes again in the fall.  We know next-to-nothing about these organisms–what eats them, how effectively they compete with algae for limiting nutrients, how well they operate at different light and temperature levels.  We didn’t even know they existed until a few years ago, and yet it turns out they are playing a central role in this long-term nitrate buildup.  Humans are also playing an important role, too, and it’s likely that changes in forest composition and nitrogen deposition over the past century put this excess nitrogen in the lake in the first place.

So, the next time you have an opportunity to gaze across Lake Superior, consider how our actions, and the lifestyle of a group of tiny microbes, have combined to dramatically change the water chemistry in Earth’s largest lake.

UST Biology’s Jadin Jackson and colleagues recently published a study in the Journal of Neuroscience. Below is a general audience description. The full article is available here.

Learning to associate rewarding experiences with the location at which they occurred is a fundamental adaptation for survival, that allows us to return to a food source or other primary reward in order to get more of something valuable. Using rats, we studied the simultaneous activity in two important brain regions involved in learning these reward-place associations and planning actions that will lead to reward: the hippocampus, involved in place and episode learning; and the ventral striatum which uses location and reward-related information for the planning of actions. We found that neurons in the hippocampus most reliably represented the location of an animal when the animal was able to predict that a reward would be available, and that ventral striatal neurons included more spatial information in their activity during this same period. Additionally, the activity of neurons in the hippocampus much more precisely locked to the time it would take the animal to reach a reward, fitting with the involvement of the hippocampus in human episodic memory. This study clarifies the information being processed by these two important brain regions and how the presence of reward-predictive cues in an environment will bias that information.

Lansink C.,  Jackson J.C., Lankelma  J., Ito R. , Robbins T.W. , Everitt B., Pennartz C.M.A. (2012)  Reward cues in space: commonalities and differences in neural coding by hippocampal and ventral striatal ensembles. Journal of Neuroscience 32:12444-12459

Can where an organism lives on the planet influence something as seemingly unrelated as how much steroid hormone they have circulating in their bodies? It turns out, yes, it can! The reason for this is that in the tropics there is a longer amount of time to potentially breed, and further away from the Tropics (toward the poles) the time available to breed (the breeding season) gets shorter and shorter. During the breeding season, males of many vertebrate species compete intensely over access to females that are ready to reproduce. The steroid hormone testosterone has an important role in ramping up males for reproduction and is typically elevated during the breeding season. Corticosterone, another steroid hormone, typically associated with “stress” and the response to stress, is also moderately elevated during this period, probably to facilitate the uptake, storage, and mobilization of energy needed for breeding. In places where the breeding season is short, for example at high latitudes, competition over females may be more intense than at places where breeding is extended, such as in the Tropics. In a recent study, my colleagues and I sought to test whether species having a shorter breeding season, and presumably more intense competition for mates during this short window of time, would have higher steroid hormones levels compared to species living in areas closer to the Tropics where there is a larger window of time for breeding. To do this, we examined variation in circulating levels of testosterone and corticosterone, as well as latitude and length of the breeding season in two major vertebrate classes: amphibians and reptiles.

The southeast Asian River Toad (left) is a tropical, low-latitude amphibian that has circulating testosterone levels 300 times lower than the high-latitude American Toad (right). American Toads can be found in Minnesota, and they have a very short breeding season, so male competition is intense, requiring lots of testosterone!

For both groups we found that male testosterone levels are higher when breeding seasons are shorter. This makes sense, because the short window of time to breed leads to intense competition among males, competition that is governed by testosterone production. In amphibians, male corticosterone levels are also higher when breeding seasons are shorter, but no such relationship was observed in reptiles. These patterns most likely reflect more intense reproductive competition experienced by males when the time to reproduce is short. In both groups testosterone and corticosterone levels are positively correlated, which suggests an energetic demand for testosterone-regulated behavior that is met with increased baseline corticosterone concentrations. Similar studies have shown some of these trends also exist across bird species. Our study shows that examining large-scale patterns of hormone levels in free-living vertebrates can offer important insights into how even very large-scale factors such as geography may influence physiology and life history traits beyond local factors, such as density, that are traditionally studied.

Jon Foley, from the Institute on the Environment, recently gave a seminar  entitled “Can we feed a growing world and sustain the planet?” in the UST Biology Department seminar. (If you missed it, you can watch Dr. Foley’s TEDxTC talk at http://www.youtube.com/watch?v=uJhgGbRA6Hk). Below are comments on the seminar by Dr. Chip Small and Breanna Arndt from our department.

On feeding the world, and reasons to be hopeful

Chip Small

The message that I took away from Jon Foley’s seminar, “Can we feed a growing world and sustain the planet?”, is largely one of hope–that agriculture must be, and can be, done in a much more sustainable way.  And yet, for me, the path towards achieving this goal is not altogether clear.  When I hear talks, or read books by scientists offering a prescription for saving the world, I can’t help but think, “Well, if the world were a dictatorship, and you were the environmental advisor to the dictator, I could see this happening.”  But the world is far more complex, and the course of action (or, more accurately, the millions of individual courses of action) that might be best for society over the long run may not be the actions that bring short term benefits to the individuals who make these decisions.  It is easy for us to criticize Brazilian farmers who cut down rain forests to graze cattle or raise soybeans, but these are entirely rational decisions–just as me driving my car to work this morning was a rational decision, albeit one that consumed a small amount of non-renewable petroleum and added a little more CO2 to the atmosphere.  All actions have costs and benefits, but the problem, as it so often is in environmental economics, is that the costs get passed on to society.  There is not a simple solution here, although there are models where conservation biologists and social scientists are working together with local farmers in developing countries to produce sustainably-grown coffee and other projects.  Whether this sort of model can scale up, and quickly, seems to be an essential question.

I also find myself reflecting on another economic question from Professor Foley’s talk.  The challenge of feeding a growing world is a double-edged sword in the sense that human population will continue to increase over the next 50 years to at least 9 billion people, and at the same time economic development in countries such as China and India is creating a higher demand for meat.  I’m somewhat troubled by the presumption that we must bring supply up to match the level of projected future demand.  Obviously we want to live in a world with food security for everyone, but this is a complicated proposition.  Modern agriculture produces more than enough calories to feed today’s population, but problems of distribution still result in food shortages in parts of the world.  Moreover, it seems to me that demand for meat may be somewhat dynamic, just as people tend to drive less when gas prices increase.  If we had to pay the true cost for meat (including all the costs currently borne by society ranging from nutrient pollution to the creation of strains of antibiotic-resistant bacteria), I suspect we would consume a lot less.

One of the final points made by Professor Foley was that, while our actions as individuals don’t really matter that much (Michael Pollan writes about his “carbon doppelganger” in China who, with each passing year is driving more and eating more meat, erasing Pollan’s own efforts to reduce his carbon footprint), we do have the potential to influence others, exponentially increasing the effect of our actions and producing real change.  In the UST Biology Department, this fall we are teaching “The Biology of Sustainability” for the first time, to 150 students.  Their new ideas, the optimism that they bring to these immense challenges, and their ability to influence so many others is truly the best reason to be hopeful.

More thoughts on feeding the world sustainably, and the role of the United States

Breanna Arndt

Dr. Jonathan Foley’s seminar last week provided eye-opening insight on the global issue of sustaining a growing population with limited resources. His talk included hard facts along with possible plans of action. This left me with a sense of urgency and energy to try to tackle the issue rather than the classic doom and gloom feeling. That being said, there is still much left uncertain.

Many themes of the seminar relate to the content of UST’s Biology of Sustainability course. Foley mentioned our increasing population due to increasing births, but also increasing survival rates. This is a good thing, but it poses a problem as we run out of space to grow food for everyone. He stated a need for more efficient crop yields more than GMOs, and the problems with overuse of water and nutrients in places like the US while places in Africa do not have enough water or nutrients to sustain sufficient crop yields.

I was surprised when Foley said that “buying local” is actually worse for the environment than buying produce coming from all over the world through places like Walmart, due to efficiency of packaging during transport. I was also struck by his remarks regarding how much water is used to produce one calorie of food and how much of that food is then wasted in this country. I have thought about how much water goes into each bundle of produce when deciding how much food to buy in the grocery store.

Foley’s suggestions for stretching our food resources further made sense, but I couldn’t help questioning the likelihood of people across the world coming together to implement them. It makes sense that reducing consumption of meat products and many other food habits would make our food system more sustainable, but it is highly unlikely that this will happen. People in developed nations like the US are not likely to give up their habits, and it would not go over well to tell developing countries that are just beginning to afford our lifestyle that they cannot engage in those practices.

I almost have to wonder if conflicts among countries would arise if American scientists going into other countries and telling them how to be more sustainable with food production while Americans continue to be wasteful here. Conflicts might kill people before a shortage of food would. This may mean that we really need to focus on getting Americans more globally minded and used to the idea of sacrificing for the common good.

Foley highlighted the fact that this is a global problem, and it is an urgent one. We need to come together, and we need to act now. The uncertainty lies in finding ways to bring about this unity and change.

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Student projects in Costa Rica – part 2: From poison dart frogs to cannibalistic tadpoles at La Selva Biological Station

The January-term course in Costa Rica, Introduction to Field Ecology course, is over. I’m sure everyone is happy to be home, but I hope the memories of the course will stay with people for a long time. I’m finally getting my life in order again, and I thought I would share some information about our final stop on the course – La Selva Biological Station – and post abstracts from the amazing projects that folks did there.

lunch time for our group at La Selva

an eyelash viper, picture from Tyler Abrahamson

La Selva was a great place for our course to visit. La Selva itself is fairly small (about 1600 hectares) but it is connected to the massive 36,000-hectare Braulio Carrillo National Park. The large combined area and the elevational gradient from lowlands to the 3500 meter peaks in Braulio Carrillo make this area a unique conservation area on the Caribbean slope. The flora and fauna are very diverse: there are over 700 species are trees at La Selva, a lot of beautiful snakes such as the eyelash viper (that many of us saw) and the dangerous and aggressive fer-de-lance (that one of us stepped on!), thousands of arthropod species such as the army ant Eciton burchelli (video), charismatic amphibians like the strawberry poison dart frog (see below), and more than 400 species of birds (representing almost half of Costa Rica’s bird species) (here’s a gratuitous baby peccary video). There’s also extensive infrastructure at La Selva. There is also modern lab space, comfortable living quarters, a cafeteria, and an extensive trail system. Some of the trails through the forest are even paved. La Selva is really wet (it gets about 4 meters of rain a year) and a lot of foot traffic on paths would quickly degrade the surrounding area. Paved paths also make it easier for researchers to travel to their study sites; the station even rents bikes that you can ride along the paths (here’s a video from some of our group). The diversity and infrastructure is part of the reason that La Selva is one of the most important places for tropical research in the world: since the station was established by the Organization for Tropical Studies in 1968, there have been over 1600 scientific papers published based on research at the site.

Our group contributed to this research output with 4 great projects. Here are their abstracts:

Factors that influence territorial calls in the strawberry poison dart frog, Oophaga pumilio

Katelyn Bojan, Maya Peters, Danny Oseid

a strawberry poison dart frog - not for licking

There has recently been growing concern regarding the potential effects of global climate change on the diversity and population density of amphibians in the tropics (Whitfield et al. 2007). Consequently, it is important to understand the behavior and lifestyle of tropical amphibians for conservation purposes. One amphibian species that is especially important is the charismatic Oophaga pumilio, the strawberry poison dart frog (video). This organism communicates with potential mates and competitors in form of bright coloration and territorial calls. Here, we investigated the factors that influence these signals by addressing: 1) the effect of call intensity and length on the magnitude of neighbor response and 2) the traits of frogs that determine response intensity. It is unknown how these frogs respond to varying calls and how they allocate their energy towards the expensive signals of bright coloration and territorial calls. There are two alternative hypotheses concerning allocation of energy towards these signals. The tradeoff hypothesis suggests that brighter, bigger frogs will call less, whereas the handicap hypothesis postulates that the highest quality individuals will have the best genes, and therefore will produce both signals equally well. We predicted that 1) longer and louder calls would signify a greater relative threat and evoke greater response calls and 2) signaling intensity would fit either the tradeoff or handicap hypotheses. We found frogs were found in disturbed areas and classified them by size (small, medium, or large) and brightness by a scale. We then played vocal recordings of Oophaga pumilio near identified frogs at half or full volume and for a length of 20 or 60 seconds, and recorded time to respond and call duration. We found that louder and longer recordings both evoked a delayed response (F_3,56 =6.17 , p= 0.0160; F_3,56 = 3.80 , p= 0.0562) and a significantly longer response call (F_3,56 =4.24, p= 0.0440; F_3,56 = 3.83, p= 0.0551). These results suggest that louder, longer calls signal closer, more aggressive opponents, and frogs recognize these as a greater threat. In addition, larger (F_2,26 =4.28 , p= 0.0246), and brighter (F_3,26 = 2.94 , p= 0.0520) frogs generally produced longer response calls. This result is consistent with the handicap hypothesis (but not the tradeoff hypothesis), suggesting that the highest quality individuals in the population are both brightly colored and have a good territorial chirp. Overall, this study demonstrates the complexity of Oophaga pumilio signaling behavior and indicates that this organism is an appropriate model system for studying behavioral ecology. Based on these findings, we hope that continued effort will be taken to conserve this species in the long term.

Whitfield SM et al. (2007) Amphibian and reptile declines over 35 years at La Selva, Costa Rica. Proceedings of the National Academy of Sciences, USA 104: 8352–8356.

Fruit Eating Fish: Pattern recognition versus initial quality assessment in Brycon guatemalensis

Evan Nolander, Tyler Abrahamson, Mark Painter, Leah Ruhland

            When foraging, animals need to make a decision on when food is worth attempting to acquire. Food quality can often be assessed directly by sampling. However, sampling opportunities may be limited when competition for resources is intense; how such competition affects assessment strategies is poorly understood. Here we examined assessment behavior in Brycon guatemalensis, a frugivorous river fish that groups in large schools underneath fruit trees. We predicted that B. guatamalensis would rely upon a system of pattern recognition for areas with elevated amounts of high quality food, rather than individual assessments of each piece of falling fruit when deciding whether or not to attempt to consume it. We conducted 3 tests to evaluate B. guatamalensis foraging behavior; we replicated each tests at 3 sites. First, we assessed how food quality affects foraging by adding either “high quality” banana pulp or “low quality” banana peel at 20-sec intervals in distinct locations. We found that significantly more fish responded to the high quality food (mean=8.19) than to the low quality food (mean=2.00, t=10.671, df=126, p<0.001), and that high quality food was consumed in less time (mean=3.29 seconds) than was low quality food (mean=13.40 seconds, t=8.883, df=126, p<0.001). In a second test, we examined the timing of food assessment by adding food with an alternating pattern of high and low quality at 20-sec intervals in distinct locations. We again found that significantly more fish responded to the high quality food (mean=5.27) than to low quality food (mean=2.95, t=4.909, df=131, p<0.001), and that high quality food was consumed in less time (mean=2.66 sec) than low quality food (mean=12.45, t=-8.128, df=131, p<0.001). Results from the alternating and non-alternating tests were compared using a two-way ANOVA, and the differences between number of fish responding to both high quality food and low quality food were found to be significantly different (F_(1,257)=26.92, p<0.001). No significant difference was found between time pre-consumption (F_(1,257)=0.03, p=0.8520). A third test was run to assess if more high quality food or a higher frequency of food regardless of quality affected foraging. This was done by adding high quality food at 30-sec intervals in one area while adding food with a pattern of high quality- low- low- low every 15 seconds to another distinct area. We found that fish responded with higher numbers in the area receiving a higher amount of high quality food (mean=7.60) than the high quality food in the higher frequency test (mean=5.35, t=2.417, df=63, p=00185). However, the high quality food in the high frequency test was consumed faster (mean=0.45 sec) than that of the low frequency test (mean=3.57 sec, t=3.312, df=63, p<0.001). Low quality food was responded to by less fish (mean=4.16) and consumed more slowly (mean= 8.81 sec). Contrary to our prediction, we found that food was both individually tested for quality as well as pursued based on pattern recognition of high quality food. Overall, it can be concluded that B. guatamalensis react to food hitting the surface in a manner of pattern recognition but use quality assessment after food enters their mouth.

Using the Island Biogeography model to determine island characteristics in tropical microhabitats 

Jordan Goetting, Amy Niemela, Tom Langer

Islands in the stream at La Selva

Boulders in streams and fallen logs provide a unique place for tropical plants to grow, making these surfaces important contributors to species diversity. The Equilibrium Model of Island Biogeography (EMIB) is a well-established model that predicts the species richness on islands based on rates of immigration and extinction. These rates are predicted to be affected by the size of an island and its proximity to source populations (the “mainland”). In the rainforest within La Selva Biological Station the boulders and logs are distinct habitats that could act as islands within their greater environment.  By accepting the EMIB as a working model of the forest, we were able to use it as a tool to determine whether or not these two microhabitats could be defined as islands. We hypothesized that species diversity on both fallen logs of a forest floor and boulders within streams would show trends predicted by the EMIB: species diversity should increase with island size and decrease with distance from source populations.  We measured the surface area of ten “islands” and the distance from each island to the nearest island at each of three different sites per microhabitat. We also measured the number of plant species on each island. As predicted, there was a significant positive correlation between island size and species diversity for both microhabitats (fallen logs: R² = 0.4643 p<0.0001, boulders: R² = 0.4041 p=0.0003). However, we found that there was no significant relationship between species diversity and distance from other islands for either microhabitat (fallen logs: R²=0.0611 p=0.1879, boulders: R²=0.0440 p=0.2840). Therefore these microhabitats follow the EMIB based on the island size but not on connectedness. This implies that colonizers are not coming from the nearest island that we measured distance to, but rather they are coming from an alternate “mainland” source. We conclude that boulders and logs within a tropical ecosystem function as ‘islands’ in certain ways to increase species diversity. This is important to take into account when clearing forests or damming streams.

Tadpoles with a side of fava beans: Cannibalistic behavior of Bufo marinus tadpoles at the La Selva Biological Station, Costa Rica

Cory Birkestrand, Liz Chambers, Braedon Wieseler, Matt Scott

The prevalence of cannibalism in wild populations of aquatic animals is often underestimated. Cannibalism may be advantageous due to the nutritional benefit of consuming animal tissue, especially where food is scarce or less nutritious. A potential consequence for cannibalistic behavior is the potential disease transmission from the deceased organism to the consumer. However, there are costs associated with cannibalism due to the challenge of fighting an equal and the potential for disease transmission from a conspecific carcass. Here, we study behavior associated with cannibalism in tadpoles of the cane toad Bufo marinus. We studied an aggregation of tadpoles on the banks of the Rio Sarapiqui in La Selva Biological Station (watch their cool movements here). Rapid changes in the level of the river caused some of the tadpoles to become trapped within small tide pools that eventually lead to their death. After the water rose, the surviving tadpoles would consume carcasses of the dead B. marinus tadpoles. Here we tested whether the tadpoles were more reluctant to consume a tadpole carcass or the pulp of Passiflora fruit from a nearby tree. We conducted feeding trials in low (<50 tadpoles/m₂), medium (50-250 tadpoles/m²), and high (>250 tadpoles/m²) density areas in natural habitat. We measured initial discovery time (the time it took for the first tadpole to begin feeding on an item) and the difference in time between the fourth discovery and fifth discovery (= “5^th discovery time”). We predicted that tadpoles would initially take longer to begin feeding on a carcass but subsequent discovery would be faster for carcass feeders due to the potential costs associated with feeding on a conspecific. We found that, at all densities, tadpoles discovered fruit faster than carcasses (p<0.0001). However, the difference between the length of the 5^th discovery time and that of the initial discovery time was much larger from carcasses than for fruit. These results suggest that tadpoles were more reluctant to feed on carcasses than on fruit, but once carcasses were fed upon by one tadpole reluctance in other tadpoles disappeared. In an isolated pool, we tested (video) whether tadpoles would become acclimated to cannibalistic feeding by examining whether discovery time would decrease on successive feeding trials. Our results showed that feeding on the carcass occurred more readily after previous exposure, suggesting that tadpoles that have previously taken part in cannibalistic activities are more likely to feed readily on a carcass in the future. Together, our results suggest that B. marinus tadpoles respond to the costs and benefits associated with cannibalism.

{Editor’s note: This semester, UST senior Nick Michalak is doing an independent study in which he is reading and writing about prominent books in Biology that are written for a general audience (the “lay public”). Here is the first of his entries.]

Nick getting some inspiration

I’m mingling at a New Year’s party this past December, when the host calls me over to chime in on a discussion her fiancé and his friend are having. I bounce over, we exchange niceties, and the fiancé’s friend confidently states, “Psychology is a soft science.” He’s a chemical engineer, proud of his role as a “hard” scientist, and he goes on to say that, “You can ask a chemist to make a certain amount of a specific compound, and he can cook up almost exactly that amount. Psychology just doesn’t have that kind of predictive power.”

I’ll spare you the details of our mostly half-baked exchanges. I do, however, want to highlight this notion of predictive power in science. Yes, a pharmaceutical engineer can take raw materials and tell you almost exactly how many kilograms of a medicinal compound he can make. A behavioral scientist can only approximate how many people will purchase that compound, and actually take it. You can say the same about the guy behind the Subway counter making sandwiches, and the party planner pondering how many people to order for. In the scientists’ case, to say that the engineer’s prediction of yield is more accurate than the behavioral scientist’s prediction of the target group’s consumption isn’t wrong, but I think the distinction is redundant. It’s redundant because these scientists are answering different questions. Electrical currents, organic compounds, vaccines, car engines, and bridges behave more predictably than do critters and people. Or maybe animal behavior is just as predictable, but the large variance in individual differences (e.g., personalities, physical traits) and features of specific environments (e.g., food sources, mating opportunities) make the task a little messier. When push comes to shove, this predictive power that people like to underscore in the old and tiresome hard science/soft science dichotomy is actually confined within the parameters of different scientific disciplines; these parameters are set by the questions these disciplines tend to answer best.

My interest in this topic was reignited when I began reading Robert Sapolsky’s book, The Trouble with Testosterone: and Other Essays on the Biology of the Human Predicament¹. In his introduction, Sapolsky, a neurobiologist at Stanford, explains that behavioral biologists are trying to understand bad behaviors by exploring connections between the body and the mind. Is anti-social behavior the result of differences in neuroanatomy, hormones, genetic abnormalities, drugs, or even junk food? Or are bad behaviors simply the result of bad people? Are diagnoses like depression or attention deficit disorder just euphemisms for sulking and “being a kid”, or are there underlying chemical imbalances and connections within the brain that are producing debilitating differences in thought, emotion, attention, and the like? If the mind is the product of our bodies and our brains (it is), then questions about people, about individualities, generalities, limits, and potentials, ought to be within the scope of not just behavioral scientists, but also natural scientists.

This common ground isn’t just easy to miss; it’s a little unsettling. Sapolsky nails it on the head when he says, “It’s easier to determine how birds navigate while migrating or how muscle fibers contract than to answer a question like ‘Is there a genetic basis to criminality?’” Chemistry, biology, and physics seem so controlled, so distant until we begin talking about them in relation to behavior. Biology is over there, but behavior…no, that’s over here. Don’t challenge our sense of autonomy with your lab coat sciences. Of course, there’s no denying the vast complexity in how people behave in comparison to how body parts work. There are just so many more variables. This is why we’ve known about the structure and circulation of the heart since the 18^th century, but we still have to question whether macroeconomists can help us prepare for a financial meltdown within a practical timeframe. But, as I’ve mentioned, these facts can be used to make silly distinctions. An anatomist or a cardiologist knows more about hearts than an economist knows about the consequences of binning the Euro in Greece. So what? The cardiologist can’t answer the economist’s problems any better, certainly not with the latest literature on heart malformations or gene therapy.

I’m not exactly sure of how a heart specialist and an economist can team up (pulmonary-economics?), but I do know that different disciplines within science offer tools that can be used to tackle complex human behavioral questions. Sapolsky’s book is a compilation of essays illuminating how biologists attempt to answer some of these questions. His goal is to bring good science to the general reader because, “When science works right, it is an amazing thing to behold—it provides us with some of the most elegant, stimulating puzzles that life has to offer. It throws some of the most provocative ideas into our arenas of moral debate. And occasionally, it even improves our lives.” I’ll continue to blog about the topics he addresses with this appreciation for science in mind, and it’s my hope that at the very least, your evaluations aren’t muddied with the idea that science deals only with exact, “hard” answers. Science deals with questions. Let’s see how biology deals with questions about behavior.

1. Sapolsky, R. M. (1997). The Trouble with Testosterone: and Other Essays on the Biology of the Human Predicament. New York: Simon & Schuster.

Maurine Neiman, formerly a post doc in our department and now an assistant professor in the Biology Department at the University of Iowa, recently had her research featured in a Huffington Post article about mating. You can check it out here: http://www.huffingtonpost.com/carin-bondar/no-eggs-no-problem_b_1250895.html

Beef and conservation in a tropical dry forest – notes from Palo Verde National Park

Entering the Palo Verde forest

A main reason that the Introduction to Field Ecology course comes to Costa Rica is so that we can use the rich biodiversity zones as natural laboratories for student-led research projects. Although there is a lot of biodiversity at individual sites, it is amazing how different the flora and fauna can be among the various sites. So far, we’ve traveled from a high elevation, oak-dominated forest at Cerro de la Muerte, to a lowland seasonally wet forest on the Pacific coast (Corcovado), to our recently departed dry forest location (Palo Verde). Visiting such different sites in a short period of time can make your head spin, but it has made for a great adventure.

marshlands at Palo Verde

Palo Verde National Park is a 19,000-hectare area in Guanacaste Province in NW Costa Rica. One main feature of the park is the extensive marshlands around the Rio Tempisque. This area provides important breeding grounds for resident bird species and feeding areas for migratory species; the Tempisque also has the highest concentration of American crocodiles in Costa Rica. In addition, the park has some of the best patches of dry forest left in Central America; the relatively open canopy in these forests make it easy to see mammals (we saw agoutis, collared peccaries, coatis, white-tailed deer, and monkeys) and snakes (here is a video of a rainbow boa that we saw).

Maya Peters at "La Roca" - a limestone perch

Tropical dry forests are one of the most vulnerable ecosystems on earth. Tropical dry forests can actually be quite wet – for example, the average rainfall at Palo Verde (150-200cm/year) is about 3 times higher than the average precipitation in Minneapolis. However, a tropical dry forest has an extensive dry season that has a dramatic effect on the biology of the system. The fertile soils and mild climates in these areas make them well-suited for human activity, including logging, agriculture, cattle ranching, and, more recently, tourism. It’s estimated that only 1.7% of the original tropical dry forest cover remains in Central America (Olson et al. 2001).

a 6-ft croc on the Tempisque

Many Costa Ricans moved into the Guanacaste region after the 1930’s to search for fertile land for subsistence farming. However, the main pressure on the forest came from 2 sources directly related to activities in the United States: timber extraction and beef cattle production. Guanacaste was a major source of mahogany, an excellent wood for building because of its workability, durability, and lack of knots. Much of the mahogany in the region was logged before 1960 for shipment to markets in the US. After 1950, much of the forest in Guanacaste was cleared for pasture. The intensity of ranching was fueled in large part by the increase in beef prices that were associated with a massive increase in demand for beef by American consumers. The impact of beef prices on forest clearing wasn’t limited to Guanacaste. This phenomenon, termed the “Hamburger connection”, led to forest clearing throughout Central and South America (Myers 1981).

Dan, our guide Raphael, Braedon, Tyler, and Evan in the marsh

Since the mid-1980’s, forest cover has actually increased significantly in Guanacaste province due to declines in beef prices and changes in socioeconomic patterns (Calvo-Alvarado et al. 2009). Ranching became less profitable in the region because the Costa Rican government withdrew their support for the industry, and because beef consumption in the United States began to decline as consumers became more health conscious. In addition, beach- and eco-tourism have become much more common in Guanacaste, and tourism is now the most important industry in Costa Rica.

the group in a cactus grove

This background provides context for our stay at Palo Verde. The accommodations at our site were simple but more than adequate: cold-water showers, bunk beds with mosquito netting, a classroom that even had air conditioning. We spent the morning and late afternoon hours out in the forest doing research projects on ant lions (Jordan Goetting, Tyler Abrahamson, Matt Scott), the bull-thorn acacia (Leah Ruhland, Maya Peters, Katelyn Bojan, Tom Langer), ant foraging (Mark Painter, Braedon Wieseler, Dan Oseid, Amy Niemala), and dragonfly activity patterns (Evan Nolander, Liz Chambers, Cory Birkestand). The mid-day “unforgivable hours” – when the temperature reached 100F – were spent resting or doing writing and data entry in the classroom. We also found time for an occasional hike to limestone promontories that looked out over the marshlands, a boat ride along the Tempisque, and a surprisingly intense soccer game. No one seemed to mind the fact that our resource use was much lower than it would be back home. Simple was good, and this theme was part of some of our late night conversations about conservation and the earth’s ecology. Given the direct connection between activities of Americans and the pressure on biodiversity preservation in this region, we begin to understand that we can really make a difference. And spending time in this amazing place should help motivate us to help simplify the American lifestyle because we can see first-hand what is being lost.

mark painter and dirty dan oseid setting up their experiment

Calvo-Alvarado J, McLennan B, Sa´nchez-Azofeifa B, Garvin T (2009) Deforestation and forest restoration in Guanacaste, Costa Rica: Putting conservation policies in context. Forest Ecology and Management 258: 931-940.

Myers N, (1981) The hamburger connection: how Central America’s forests became North America’s hamburgers. Ambio 10: 3–8.

Olson DM, et al. (2001) Terrestrial ecoregions of the world: a new map of life on earth. BioScience 51: 933–938.

 

Maya, Leah, and Tom working on the acacia-ant mutualism

Cory, Liz, and Evan observing dragonfly flight behavior

Student-led ecology projects in a remote tropical forest

Lab courses in Biology provide students with training in many aspects of the scientific process, but students rarely have the opportunity to come up with and develop their own research questions. The Introduction to Field Ecology course,  which is organized almost exclusively around student-led projects, is an exception. The course travels to sites in Costa Rica for a month. Students spend a couple of days at each site making observations which they then use to generate a question about the ecology or behavior of organisms at the site. They then develop an experimental design, collect data to test predictions, and present their findings to the group. It is a great opportunity to employ their creativity, inquisitiveness, and effort to the process of discovery.

We recently finished a week-long stay at Corcovado National Park in SW Costa Rica. All of the students did amazing work. Below are abstracts from each of their projects. Videos and pictures from their studies are embedded.

Amy and Leah observing spider monkeys

Relationship between social structure and lifestyle habits in co-existing monkey species in Corcovado National Park

Amy Niemela, Mark Painter, Leah Ruhland, Matt Scott

a capuchin monkey

Much of the world’s biodiversity is in tropical forests. Similar species often coexist in the same location, but the factors that allow for their coexistence are often unclear. Monkey species in Neotropical forests are known to have a variety of distinct behaviors and social organizations.  In some species, the alpha male fills the role of a lookout when the rest of the troop is foraging, while in others, each individual looks out for itself.  Social structure can affect movement patterns through the canopy in a similar way in regards to how mothers caring for young respond to challenges when moving from tree to tree.  To test potential relationships between social organization and foraging or movement habits, we performed an observational study in Corcovado National Park on three coexisting monkey species: spider monkeys (video), howler monkeys, and white-faced capuchins (video).  We measured forager vigilance by comparing the amount of time spent surveying surroundings to the amount of time focused on foraging.  We then compared vigilance among species in both the presence and absence of an alpha male lookout.  We measured movement patterns by counting the number of gaps in the canopy from one tree to another that an individual crossed in the observed time, as well as the number of times that the individual jumped in the same period.  We found that capuchins, howler monkeys, and spider monkeys had significantly different levels of vigilance when foraging.  In addition, individuals foraging in the presence of an alpha male lookout were significantly less vigilant than individuals in troops where the lookout role was not clearly defined.  Capuchin troops never employed a lookout and individuals spent much of their time being vigilant. In contrast, howler monkeys always had an alpha male lookout and individuals were rarely vigilant. Half of observed spider monkey troops had a lookout, and individual vigilance was significantly higher in the absence of a lookout.  In regards to movement patterns, mothers faced a similar number of canopy gap-crossing situations as non-mothers. However, mothers jumped at a significantly lower frequency than non-mothers across all species.  This result suggests that, in any species, the role of caring for young affects risk-taking behavior when traveling through the canopy.  Overall, we conclude that there is a clear relationship between community roles and foraging and movement patterns in these three monkey species.

Size-based differences in territorial displays and activity levels in the common basilisk (Basiliscus basiliscus) in Corcovado National Park

Cory Birkestrand, Katelyn Bojan, Liz Chambers, and Jordan Goetting

Basiliscus basiliscus in Corcovado

Competition for territories containing prime resources is common behavior for many organisms. Some species maintain territories by displaying aggressive behaviors while others must actively search for resources. The common basilisk (Basiliscus basiliscus) is a Neotropical basking lizard found in lowland areas near rivers and streams. Male basilisks are territorial, holding and defending their territories by exhibiting aggressive head bobbing and chasing behaviors. In this study, we examined the relationship between size, distribution, activity level, and territorial display of the common basilisk. We predicted activity levels and territorial displays would be higher in smaller basilisks because small basilisks compete for territory with lizards of all sizes, whereas larger basilisks typically only compete with basilisks of similar size. We conducted 11 30-minute observations over a 3-day period (see videos of Cory here, of Katelyn here, and of a small basilisk here). We classified basilisks by size (small, medium, or large), number of head bobs, and number of dashes for each observed basilisk. We found that small lizards were more active (p<0.0014) and exhibited more territorial displays (p<0.0001) than medium or large lizards. It was also found that small and large basilisks generally occupy distinct areas within each habitat. Our observations suggest that small lizards may have higher activity levels and exhibit more territorial displays because they must move around and compete with basilisks of all sizes for territory and resources, whereas large basilisks have larger, more established territories. Large basilisks only take action to defend their territory when others of the same size challenge them. Also we suggest that small and large lizards occupy distinct areas within their habitat because large basilisks are more dominant, and therefore occupy the most preferable and protected areas, whereas smaller subordinate basilisks are forced to occupy marginal areas of the habitat.

Trade-off Between Safety and Food Acquisition in Terrestrial Hermit Crabs

Maya Peters, Tyler Abrahamson, Braedon Wieseler

Tyler, Braedon, and Maya investigating hermit crab behavior

Animals often face a trade-off between acquiring food and staying in safety. However, the nature of this trade-off may differ among individuals with different characteristics, and it may also differ across environmental conditions. Here, we investigate foraging-safety tradeoffs for terrestrial hermit crabs (Coenibita compressus) (video of crabs eating coconut) at Corcovado National Park, Costa Rica. This species is found across a gradient from exposed beach, to a beach-forest transition zone, to the margins of the forest. We examined whether crab behavior suggests they face a trade-off between acquiring food and defense, and we determined whether the response to this tradeoff depended on crab size and environmental conditions.  We tested defense response by using a stick to mimic a bird attack (birds are major predators of this species), and we compared these responses in the presence and absence of food. Our main results were that larger crabs spent more time in their shell after a simulated predator attack, but only in the absence of food. In addition, crabs without food were particularly slow to emerge from their shell after facing a threat in the forest or on the beach. Because crabs were most abundant at the forest-beach transition zone, our results suggest that predation threat is a major factor determining the distribution of hermit crabs in this environment.

Size and food acting as determinants of interactions in the freshwater shrimp, Macrobrachium americanum

Tom Langer, Evan Nolander, Dan Oseid

The shrimpers doin' some shrimp'n

Why do some organisms exhibit territorial behavior, while others do not? One explanation is because the benefits of being territorial depend on ecological conditions. Macrobrachium americanum is a freshwater shrimp common in lowland tropical rainforests and size-dependent behavioral interactions among juvenile M. americanum can easily be observed in low-flow pools. Based on general observation, we classified juvenile M. americanum into three categories of size, small, medium, and large. Observational and experimental data were collected from eight pools in two streams found in Corcovado National Park and analyzed by viewing densities and numbers of interactions between sizes in the presence and absence of food. Data were analyzed using a two-way ANOVA and Tukey’s HSD test. We found that size of shrimp (F_1,5=21.94, p<0.0001) significantly affected the number of interactions among shrimp; the most common type of interaction was medium-sized shrimp interacting with small shrimp. Interaction frequency also generally increased when we added food to natural pools (F_1,1=18.73, df=1, P<0.0001) In addition, there was also a significant size-by-food interaction (F_1,5=2.77, P=0.0228) because interactions involving medium sized-shrimp became more frequent relative to other interactions in the presence of added foods. Our results suggest costs and benefits of territorial interactions differ among different sized individuals in this population. Future work should determine the ecological factors that account for these differences.

In the land of endangered species – sightings of the Baird’s tapir

Liz's picture of a male tapir on the beach in Corcovado

Our Introduction to Field Ecology course spent last week at Corcovado National Park in SW Costa Rica. This park is the largest protected area of lowland forest on the Pacific coast of Central America. Larger parks can support populations of animals that have large home ranges, special habitat requirements, or are particularly at risk when in proximity to human settlements. Many of these species – jaguars, white-lipped peccaries, and scarlet macaws – are abundant in Corcovado, and they are one of the reasons why this place is such an exciting location to visit.

Braedon's picture of a baby tapir in the Rio Claro

Probably our most exciting animal sighting at Corcovado was the Baird’s tapir, Tapirus bairdii. Baird’s tapir is the largest non-domesticated land mammal in Central America. It used to be abundant across its range from southern Mexico to northern Columbia. However, in 2002 it was listed as Endangered by the International Union for the Conservation of Nature (IUCN), which estimated that there were only about 5000 tapirs left in the wild. This number is down by at least a 50% in the last 30 years, and it’s expected to drop by at least another 50% in the next 30 years.

Tapirs don’t have many natural predators. They’re big animals (about 2m long and 1m high) that are likely only attacked by big cats (jaguars and pumas) and crocodiles. These predators are themselves rare. Instead, the threats to tapirs are related to human activities: habitat loss, hunting, and transference of disease from domestic animals. About 70% of forest land in Central America has been lost in the last 40 years, and much of the remaining forest has been fragmented. Fragmentation is particularly detrimental to tapirs because small fragments are unable to maintain viable tapir populations. Even though tapir hunting is generally illegal across Central America, poaching laws are rarely enforced. Larger parks like Corcovado have guardians, but there are usually far too few park rangers to eliminate poaching. There has been speculation about disease transmission from cattle and horses. It’s probably important, but the magnitude of the threat isn’t yet known.

many of us with our honorary class member, a male tapir

Luckily for us, Corcovado still has a moderate number of tapirs and most of our group has been able to see one. Liz Chambers and Tyler Abrahamson took several pictures of a tapir on the beach. Our group kept their distance (tapirs have been known to charge humans that get too close) but they were still able to get great photos, including a nice group shot with the tapir in the background. In addition, Matt Scott took this amazing video of a male tapir walking near the ocean at low tide, and Tyler Abrahamson took this great video of a tapir in the surf. Tapirs in the surf aren’t looking for food – they eat fruit and leaves in the forest. Tapirs are good swimmers and they like to wade in the ocean or rivers to cool down and to get rid of ticks and other ectoparasites.

Spending time in Corcovado has made us think a lot about whether it’s possible to create a sustainable human society. Can we control resource use and reduce environmental degradation such that our current biodiversity is maintained over the long term? Watching a tapir walk through the surf gives me a sense of urgency; I want to help preserve places like Corcovado so that we can bring our kids and grandkids to see these amazing creatures.       

This January, UST senior Abbie Bruning is conducting research in Panama on how diet affects social immunity in the ant, Ectatomma ruidum. Since January 3rd, she has been on Barro Colorado Island in the Panama canal zone conducting research on her own. Below is a description of her experiences:

Abbie at work in the lab on BCI

A stint on Barro Colorado Island (Panama) in the dry season – by Abbie Bruning

                Coming back to Barro Colorado Island (BCI) has been a fun and exciting experience. I was previously on the island May through July of 2011. The atmosphere of the island is much different this time of year compared to the summer months. This is not only because the number of researchers are significantly reduced but also because, starting mid December, the dry season begins. During the dry season temperatures raise slightly and the humidity drops. The significant characteristic of the dry season is the large reduction of rain fall. During the rainy season there is a 40% to 50% chance of rain everyday which makes it very difficult to stay on schedule with field work. While during the dry season you’re lucky if you get a five minute cloud break from the sun, as my Irish skin can attest. (I am still trying to figure out how I got a sun burn while working under the rainforest canopy all day.) My first few days on BCI, my professor Adam and I collected ant colonies almost every day; it would have been impossible to have done that in the rainy season. (Here is a video of Abbie walking the stairs going into the forest. Here is Abbie going into the forest. She’s not wearing field clothes – this was a quick excursion to a canopy tower)

the "Ambient Soil Lab" on Barro Colorado Island

Because of Adam’s help we were able to get the project off and running before he left to go lay on a beach somewhere in a tropical paradise (or to instruct a field research course in the rough terrain of Costa Rica… same thing). Besides the first two weeks I will be working with the colonies of the ant Ectatomma ruidum in the main lab as well as in a building we call the ambient soil lab, which is located back in the forest. Because I didn’t spend as much time in the lab this past summer I failed to notice that the spider monkeys use the lab clearing as their own person playground and that tarantulas set up camp in the cinder block steps outside the back door.

Though BCI is very quiet this time of year the traditions of the island still persist. One running tradition is the Thursday night Bambi talks. These weekly seminars were started initially for researchers beginning in the field to get their feet wet and receive fed back on their work. It is said that the name comes from the idea, like Bambi, that you need to learn to walk before you run. Researchers from Panama City and Gamboa (the nearest town on the mainland) come to the Island for the weekly seminar; the influx doubles the population of BCI. This talk became rather formal over the years so a second less formal seminar, called the Capybara, was created to take over the role that the Bambi once held.

Abbie at the "big tree" on BCI

Another running tradition is “morning walks with Bert”. Egbert Leigh (Bert) is an evolutionary biologist and a recent retiree of the Smithsonian Tropical Research Institute (STRI). It’s hard to fully capture Bert’s presence and role on the island. Bert has lived on the island for years. His children, who are grown, lived and spent most of their childhoods on BCI. On his morning walks he takes young researchers out hiking and discusses plant species, evolution, and literally anything under the sun. Many times for me, and I assume for some others, it’s a little over my head (ok way over my head) but it is a very fun learning experience. Bert also often invites researchers and interns up to his office for a scotch after dinner. The “office” is up on hill. Inside, there are books and journal articles everywhere, and harpsichord music is often playing in the background. Bert will talk at length about ecology, conservation, academia, politics, world history, religion, you name it. It can be a surreal experience. In fact, the entire experience on BCI, from the weekly seminars to the nightly gatherings on the balcony after a long day in the field, is intellectually engaging.

Reflections on culture and ecology in Costa Rica – by Leah Ruhland and Evan Nolander

Most of our course – Introduction to Field Ecology – in Costa Rica focuses on ecology research projects at various locations across the country. However, on our first day in the capital city, San Jose, we ask students to visit a cultural site and to write about how this aspect of Costa Rican culture has affected or is affected by the natural world. We had many great submissions, but we picked two exceptional posts for the blog. Here they are:

A visit to the Gold Museum – by Leah Ruhland

            While in San José, I walked with a group of my fellow students, along the street called Colón, to the Pre-Columbian Gold Museum. While at the museum, I learned a lot about how the presence and use of gold shaped the history of Costa Rica and the culture of its people. I was able to learn about how the trajectory of gold mastery and usage affected the relationship between the nature of the country and the lifestyle of the indigenous people.

The indigenous people of Costa Rica saw gold as a precious item that was to be used for rituals and ceremonies. One specific ceremony in which the use of gold was highlighted was in funerals. One funeral rite known as “ceremonial killing” was a key part of the burial process. In this ritual, an item of gold, stone, or ceramic was intentionally broken or pierced. This was done to completely disfigure the object being used and symbolized the disfigurement of the deceased on earth since they were no longer existing in the same physical form. Gold was incorporated into the trade practices of the natives with other villages to purchase a variety of needed goods such as food, clothing, wood, and pottery.

Artifacts at the Gold Museum in San Jose

The abundance of nature all around the indigenous peoples in Costa Rica made it natural for them to pull this inspiration into their gold creations. The diversity of natural features allowed for the ability to create many different diverse designs, many of which were dependent on the local area in which the person was living. An example of this is of the people who lived on the coasts drew inspiration from marine life and animals such as frogs and fish. All the natives incorporated a lot of natural features such as mammals, plants, people, insects, birds, amphibians, and other organisms into their designs. Another aspect unique to the Costa Rican culture was their tendency to integrate human and animal features in their final gold designs. The creation of disks, diadems, and pendants were also popular designs that were made.

In 1502, the Spaniards reached the Caribbean coast of Costa Rica. The exchange of Old World objects and native gold pieces occurred between the Costa Rican people and these new arrivals. These trades would change the future of the native people who had lived there for thousands of years. The further conquest of the Costa Rican land shattered the lifestyles both politically and socially of the indigenous people permanently. Because of this colonization, the artisan traditions that had made progress over the many years of development were no longer needed to produce the gold objects for the purposes of before and the gold craftsmanship of these people ended up dying out.

The main technique used to extract gold by both the native and the Spanish conquerors were set up in a similar manner. In order to extract gold from the beds and banks of rivers, a terrace was built to be used. Sand that was stirred from the river bottom comes to rest at this terrace. The current of the water is used to separate the lighter materials from those that are heavier, like gold, which are deposited at the bottom. Then this material was washed in a large, porous tray with circular movements until the desired gold product began to appear. This technique is still effective for small-scale extraction today. Some clearing of forests and land area is required to set up these systems. In the future, gold mines would be set up, and excavating on a large scale would cause the tearing down of large areas in order to collect larger reserves of gold for profit.

The natural world of Costa Rica influenced the way the native people viewed and used gold in many different ways. One main connection that the natives had with nature was in how the objects they depicted in gold were of natural items that they experienced in their daily lives and found inspirational. They saw nature as a gift to be protected and admired and showed these feelings in honoring nature in their gold creations. The natives of Costa Rica understood that the earth provided them with all the necessities in their lives. They respected this relationship by using their resources sparingly and only when needed. This included how they viewed and used gold since they didn’t believe that it should be exploited or used in excess.

Importantly, the arrival of the Spanish in the 1500’s had a significant impact on the natural world in Costa Rica. Spaniards changed the original use of gold and other resources that they saw to be valuable when they arrived and conquered indigenous people in this area. They exploited gold as a commodity that needed to be used exclusively for profit. If gold, or any other objects that were valuable, were not collected in as large of quantities as possible, then they considered these objects to be going to waste. They cleared out many different areas and trees to build terraces to be used for small-scale extractions in search of gold to be sold in Europe for profit.

Exploitation of the natural world by humans has been around since the beginning of time. With the continued movement towards modernization in our world, the human population is constantly acting in ways that hurt and destroy our environment without a second thought. Thankfully, research is revealing evidence that we cannot continue acting in such selfish ways if we wish to continue to survive. Continued awareness and movements towards a more eco-friendly way of life are still necessary, however, if we hope to have any chance in saving the world in which we live.

 A change in perspective – by Evan Nolander

On my second day in Costa Rica, I journeyed into the city center in search of the defining characteristic of the Costa Rican people, a characteristic that really separated them from everyone else. I spent time in parks, restaurants, shops and the streets discovering that rather than the differences between societies being what struck me, it was all of the similarities. I saw mothers walking hand in hand with their children and scolding them for wandering too far, elderly couples slowly meandering down the street, men and women in suits bustling from their place of business to their cars or buses, hot pink haired teenagers with piercings through every conceivable section of their face, and in the end, I realized that I could have easily been standing in St. Paul. McDonalds was on this corner, KFC on that, both bustling. Throughout this, I found myself becoming a bit depressed and downtrodden at what I believed would be an incredible, indigenous experience had really just turned out to be a continuation of commercialized society.

Sculpture with nature images in San Jose

However, as I continued through the city I ended up at the Jade Museum of Costa Rica, where the history of the natives was traced from the early hunter-gatherer nomads who settled in an area that was once 98% forest and created the country seen today. Though it wasn’t a modern experience in the parks, streets or restaurants of San Jose, it provided me with an incredible view of the beginning of Costa Rican society and began to show me that, below the surface, there is a truly unique, proud history and feel to the Costa Rican people. The museum provided information on the most basic beginnings of the settlement of the early Costa Rican natives and thus exploitation of land by humans. In order to settle in one place, agriculture and communities were necessary. In order for this to proceed, land needed to be cleared and animals needed to be hunted. However, a unique angle was provided by the Jade museum that took this desire for progress and allowed it to be seen instead as a desire for the acquisition of power. Though jade wasn’t mined in Costa Rica, it was acquired through the trading of goods taken from the land. This jade was used to make headdresses and jewelry for the prominent people within each chiefdom, like powerful families, caciques and shaman. It was in this exploitation of land that the very first example of materialism arose, and personal power took precedence over the health and survival of natural resources. This realization, combined with the commercialization I had seen on the streets of San Jose, initially left me believing that this pattern had continued until today and was the cause for my earlier feelings of disappointment. However, this changed as I began to look and learn more about the prides of the people.

In every establishment, and in almost every public park or display, a theme of nature began to emerge. Rather than the normal run of the mill artwork that is used to decorate cities and establishments, almost everywhere was a depiction of a native plant or animal of Costa Rica. As this realization hit me and I began to think more, I realized that rather than people continuing to care about nothing but power and themselves, at a certain point the people of Costa Rica must have realized that many of the things that identified them were quickly disappearing, something that unfortunately may not be happening in many other places in this world. This realization has created a people who put into motion programs to save their forests from massive amounts of agriculture, and a people who took great pride in displaying what it was that made their country unique at the most basic, ecological levels. This belief was only driven home more when we had the incredible opportunity of visiting a biological research station at Cerro del Muerte, a national park area that had been saved in the same fashion as numerous others in Costa Rica. It was here that I saw Costa Rican pride had flourished in the most pure and inspirational way.

Don Carlos - our host at Cerro de la Muerte

In Cerro del Muerte we had the opportunity to see a group of people that took the greatest pride in living in equal balance with nature and humanity, not tipping to either extreme. Rather than staunch conservatism where humanity is suffocated for the sake of nature, or reckless treatment of the environment where all our resources are destroyed through ignorance and selfishness, a group of people had found a way to build a reserve that was self-sufficient. The area contains a completely self-contained, organic trout farm that runs off water from numerous streams in the area, so as to not deplete one stream too much. The water from the trout farm runs through a hydroelectric generator that powers the homes within the reserve. The trout are fed with worms, which are grown in the organic waste that comes from the humans, cows and horses that live on the land. Some trout are sold, and with it the goods that can’t be grown are bought. Buildings are built from trees in the area, and new trees are planted every year. Seeing this with my own two eyes provided me with a real understanding at how simply, but effectively these people have made an effort to find a way to thrive while allowing the natural ecology around them to thrive. Though it’s only been a short period of time, I feel that I’ll be able to really appreciate the ecological and cultural aspects of the other parks we’ll be visiting in the next three weeks.

From the overlook at Cerro, with Mark Painter, Danny Oseid, Tony Lewno, Maya Peters, Leah Ruhland, Evan Nolander, Matt Scott, Tyler Abrahamson, and Katelyn Bojan

Walking to the “most biologically intense place on earth”

Corcovado National Park in southwestern Costa Rica is an amazing place to visit. It is one of the last large expanse of lowland tropical rainforest in Central America. Lowland rainforest is particularly important for conservation because much of the biodiversity in the tropics is located there. Unfortunately, lowland rainforest contains valuable tree species for logging, and it’s relatively easy to convert into agricultural land. Forest conversion not only destroys natural habitat, but the resulting habitat fragmentation makes it difficult to maintain viable populations of organisms with large ranges. Corcovado, with 263 square miles of continuous forest, is the largest primary tropical forest on the American Pacific coastline, and it is home to populations of some of the rarest animals in the New World tropics – Jaguars, Baird’s tapir, harpy eagles, scarlet macaws, white-lipped peccaries, and the Central American squirrel monkey.

Our class – Introduction to Field Ecology – is currently staying for a week at the Sirena ranger station in Corcovado. Getting here is not easy. One option is a 15-min flight from Porto Jimenez on a small plane. Two of our students, Braedon Wieseler and Amy Niemela, volunteered to fly in with all of our equipment. They saw the pristine forest from above, and bravely endured the landing on the little airstrip cut out of the forest near the station.

The rest of the class made it to Sirena by traveling across the Osa Peninsula from the little town of La Palma. We traveled the first 10 km in an old military vehicle; most of the habitat was subsistence farms (banana and oil palm) and river beds. One of the highlights was seeing the rare King Vulture perched on a branch overlooking a dead horse in the riverbed. Another highlight was seeing pairs of scarlet macaws flying in unison above us.

the riverbed on the way to Corcovado

The second part of the excursion was a 23km walk through the forest. Walking 23km through pristine rainforest is the type of experience that one never forgets. Check out some video here and here. Sure, it was hot and humid, and the blisters are still healing, but the sight of huge palm fronds, giant strangler figs, the occasional spider monkey group, and all of the other biological complexity was enough to keep our spirits high throughout. It took us about 7 hours, and was the most demanding hike some folks had ever taken.We knew we were close to the station when we started hearing the crashing waves of the Pacific.

a giant strangler fig at Sirena

Evan Nolander in a contemplative (RSC) moment

a break during the walk to Sirena for Katelyn Bojan, Leah Ruhland, and Maya Peters

Emerging from the forest at the Sirena station was exhilarating. There are a few tourists here (that come by plane, boat, or an equally long hike along the beach), and a small staff. All of the supplies for the station are transported in by boat or plane. The station has photovoltaic cells for generating some electricity, but power is only available here for about 3 hours in the evening. There is a kitchen that makes us 3 hardy meals each day, but there are no other supplies available. Our group is in bed by 9:30 and up at 6, unless someone takes a morning hike at 4 (the pristine beach is a popular location). Everyone is excited about being here and they are developing interesting research projects. We’ll report on those in the near future.

Field Ecology in Costa Rica – A Visit to the Mountain of Death

This January, 14 UST students and 2 instructors are taking part in a field ecology course in Costa Rica. We’re going to visit a variety of forests and ecosystems, ranging from classic lowland tropical rain forest to the endangered tropical dry forests to misty, montane cloud forests. The focus of the course is teaching students how to conduct field-based ecological research. Costa Rica is a great environment for teaching field ecology because there is so much biological complexity. In this environment, students can come up with their own research questions and carry out simple observations or experiments to address them. It’s exciting for everyone when someone is able to discover something new about the biological world using simple tools, ingenuity, and the scientific method.

Our first stop was the capital city, San Jose. Students worked on a statistics assignment on the patio of our hotel. It was a tough assignment, but working on it with a view of the mountains in the background sure beat a sterile classroom in frosty St. Paul.

Cory Birkestand, Mark Painter, Matt Scott - Stats in San Jose

Our next stop was Cerro de la Muerte (Mountain of Death), a high elevation site about 3 hours SE of San Jose.  Cerro de la Muerte is in the Talamanca range, which extends from eastern Costa Rica into western Panama. According to Wikipedia, the name comes from the fact that, in the past, crossing the mountains from the central valley meant a three or four day journey and many ill-prepared travelers succumbed to the cold and rain. Well, it’s certainly misty and chilly but we’ll take care of each other so that no one will succumb to the elements while we’re here!

epiphytes everywhere at cerro de la muerte

Cerro contains many endemic species and interesting habitats. Many of the trees are covered in epiphytes – plants that grow on other plants. It’s so wet that there are sometimes epiphytes growing on epiphytes! Risk of UV damage is high because of the thin atmosphere at this elevation, and many plants have adaptations for dealing with UV stress. One thing that seems odd about this habitat is that there are close relatives of temperate species. For example, there are a lot of oak and alder trees, and the bird fauna include robins, finches, thrushes, wrens, and juncos. One place we’re excited about seeing is the paramo, which has stunted shrubs, dwarf bamboo, and tree ferns, and smaller plants like blueberry, gooseberry and lady’s slipper.

the field station at cerro de la muerte

Our field station at Cerro is a trout farm that aims to have minimal ecological impact. It’s an amazing place. One of the owners, Carlos, has raised trout on the land for over 20 years and has built much of the infrastructure. The trout farm is impressive. There are a series of tanks and ponds that are used to provide fish at different life stages with the conditions they need to thrive. The fish are fed a variety of food, including worms from compost supplied with on-site kitchen waste. Matt Scott made a cool video of the trout – it’s here. Carlos explained that his trout farming operation is completely organic, and that he has developed and optimized his own organic techniques over the last 20+ years.

There are a lot of admirable qualities about this place. Much of the electricity for the station comes from a turbine that is powered by a stream on the property (Evan Nolander explains the process here). The buildings and furniture are constructed primarily with oak and alder that has been harvested locally. Almost all of the food comes from local sources. Carlos emphasized that the most important thing to keep in mind when living here at this station is maintaining balance. For example, whenever any trees are cut down and used for building material, he makes sure to plant more seedlings in order to ensure that the forest’s diversity is preserved. He proudly demonstrated this by showing us trees he planted 25 years ago that are now flourishing in the forest, as well as seedlings of the endangered palm tree that he plans to plant in this area to ensure the survival of this species. Being here gives you a sense that it’s actually possible for humans to live sustainably. And so far, the simplicity of the life seems to suit us well.

Student research in Panama – the beginning of an adventure

Today UST senior Abbie Bruning and I are traveling to Barro Colorado Island (BCI) in Panama to start a research project

Abbie with friend

on social immunity in ants. Abbie is going to be on BCI through January and will write several entries about her experiences. Today we wanted to write a quick entry describing a bit about our travels, with some information about Panama and the history of BCI thrown in.

Panama has been undergoing an economic boom over the last few years and signs of modernization are everywhere. The skyline of Panama City looks like Miami – glossy new skyscrapers pressed right up against the beach. But it’s really stressful in Panama City. It’s very noisy – drivers honk constantly (what are they honking for?) – and filled with smog. Crossing a street is treacherous – you just have to go for it. Luckily, there are some cool out-of-the way hostels that give some respite. A fun place to go is Luna’s Castle in the old part of the city (Casco Viejo), which still has a lot of old french colonial architecture – some it well-maintained, some of it crumbling.

the crumbling charm of casco viejo

We were able  to bypass Panama City on this trip, as we left St. Paul early and are able to make it all the way to BCI in one day. From the airport, we took a 1-hour taxi ride to the town of Gamboa, which is in the Panama Canal Zone. In Gamboa, we sit on the docks for an hour or so watching huge tankers travel through the canal (a video of Abbie’s description of the trip is here). We then take a 45 minute ride up the canal in a “water taxi” (video).

Barro Colorado Island was formed in about 1913 after the damming of the Chagres River. The damming of the river was a key step in creating the Panama Canal. The original attempt to create a canal in Panama was led by the indefatigable Ferdinand de Lesseps, who had also overseen the successful completion of the Suez Canal. De Lesseps, with the backing of the French government, insisted on building a canal at sea level. A main impediment to the construction was that the rainy season would turn the Chagres into an unstoppable force that would wipe out much of the progress made during the dry season. The French effort was abandoned in 1890 after numerous setbacks, deaths due to diseases such as yellow fever and malaria, and financial mismanagement. The United States picked up the effort in 1904 and began building a lock-style canal. The Gatun Dam of the Chagres was built between 1907 and 1913. It created the Gatun Lake at 85-ft above sea level. Locks lift ships up to the level of Gatun Lake, and then much of the transit across the Panama isthmus occurs across the lake instead of a traditional canal. A great history of the Panama canal is “The Path Between the Seas” by David McCullough. BCI is a 1500 hectare former hilltop that is now in the center of the canal zone.

BCI was set aside as a nature preserve in 1923. The only permanent structures that have been on the island since its formation are buildings associated with a field station run by the Smithsonian. The station is probably the most famous field station in the New World – much of what we know about the biology of the new world tropics is because of research that has been done at this site. This station is where Abbie is going to stay for the next month. (see the cool video of us arriving at BCI here). Almost all of the island is made up of pristine forest, filled with white-faced and howler monkeys, ocelots, and three-toed sloths. Abbie will be able to spend her days walking through the hilly terrain listening to the sounds of the forest (while thinking about ants). There are very few people here at this time of year, so Abbie will be spending much of her time alone. Luckily there is a staff that will provide her with three buffet-style meals each day. These comforts allow her to focus on the work and the experience of life in a tropical rainforest. Let’s hope she comes back and doesn’t end up like Mr. Kurtz in Joseph Conrad’s Heart of Darkness.

I am not a fathead

I remember an episode one summer day when I was a teenager. I was daydreaming while I was riding my bike and I rode through a stop sign into an intersection. There was a car at the stop sign on the cross street and a tough-looking guy was watching me while leaning out his open window. He had started pulling out into the intersection and I almost hit him. As I clumsily tried to stop, the only thing he said was “fathead”. And then he drove off.

Well, I do have a big head. But all humans do. Brain mass:body mass ratio is higher in humans than in most other mammals (although it’s certainly not highest in humans – see comment below) ; it’s about 3 times larger than is the ratio for our closest living relative, chimpanzees. So, instead of “fathead”, “encephalized” is a more appropriate description of my appearance.

Why are we humans “encephalized”? Brains are costly to maintain, so animals with larger brains must either have higher overall metabolic costs or have reduced maintenance for other metabolically active tissue. This latter idea has been called the “expensive tissue hypothesis”. It proposes that mammals decrease investment in expensive tissues (like the gut) to fund relatively large brains. This is a classic example of a tradeoff – using more resources for cologne means less money for dinner on your date.

In the most recent issue of the journal Nature, Navarette and colleagues tested the expensive tissue hypothesis using data from 100 mammal species. They found no evidence that mammals with larger brains had relatively smaller guts or that any other major organ was smaller. So much for the expensive tissue hypothesis.

Navarette and colleagues did find evidence for one tradeoff: mammals with larger brains have less body fat. Fat stores aren’t expensive to maintain, but carrying them around might make it harder to avoid getting eaten – luckily for us there aren’t tigers roaming the mall. The authors suggested this fat-brain tradeoff reflected alternative starvation resistance strategies: fat stores offer a “physiological buffer” against starvation, and big brains offer a “cognitive buffer”. In other words, you don’t need to pack on the fat if you’re smart enough to figure out how to get food when times are tough. This tradeoff doesn’t seem to exist in primates. For example, we big-brained humans also carry a lot of fat (14-26%) compared to chimpanzees (3-10% body mass). Navarette and colleagues suggest our efficient form of locomotion – bipedalism – may allow us to be both fat and “encephalized”. Go humans.

So, I’m not “fatheaded”. I’m encephalized and this provides me with a cognitive buffer against starvation resistance. I wish I could have said that before that guy drove off.

Perspective of an Undergraduate – Attending the ESA meeting in RENO 

(This is a guest post by Katie Miller, a senior Biology major)

Although intimidating as it might be for an undergraduate student to hop a plane to a new place they haven’t been before, possibly by themselves, and attend a big scientific meeting, I believe that it can be an extremely enriching experience. Recently, I temporarily vacated my undergraduate classes to attend the Entomological Society of America meeting in Reno, Nevada. For those who don’t know, this is the largest insect meeting in the world where scientists from almost every continent attend to present their research and attend professional networking and collaborative meetings. Upon the looming date of departure to the meeting, certain troubling thoughts occurred to me such as: “what if I don’t see anyone I know?”, “what if I mess up my presentation?”, and “what about my coursework!” Despite the potential hazards of attending a scientific meeting during the semester, there are numerous benefits that an undergraduate student can gain from attendance. During the meeting, I had a variety of different opportunities to learn about hot topics in Entomology and Ecology and about research related to my current project on ants.

One talk I attended was by Ben Hoffmann from Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia on “Invasive ant eradication – history, global status and requirements for improvement”. Biological invasions can have devastating impacts on ecosystem function and are one of the main threats to biodiversity globally. Successful eradications are rare. For ant species, there are only ten recorded cases of successful eradication of an invasive ant even though eradication efforts have been going on for nearly a century¹.

No doubt the increase in global commerce is a major factor behind the increase in ant invasions, requiring even greater management actions. It certainly doesn’t help that there are folks out there attempting to actually sell invasive ant species (http://myrmecos.net/2011/11/19/world-of-ants-store-sells-extreme-pest-insects/)! Hoffmann discussed the fact that most eradication programs begin well after populations have been established, making success much less likely. There is also a lack of understanding of how ants process food within a nest, making effective food baits more difficult to develop. Furthermore, there are underdeveloped links between researchers and rangers/managers (at least in Australia…not sure about the U.S. but I wouldn’t be surprised if there are similar problems in the U.S.). Managers are not necessarily required to publicly communicate strategies or results of their program and as a result there is a lack of publication of project outcomes. I am deeply concerned about the ever increasing species extinctions and subsequent decreases in biodiversity occurring as a result of human impacts and thus I find it particularly important that people become aware of issues such as the problems Hoffmann highlighted in his talk.

Another talk I went to by Cleo Bertelsmeier, which focused on a database website called Ant Profiler (http://www.antprofiler.org/) set up to record ecological characteristics of ants including morphology, behavior, habitat, nesting, distribution, and invasiveness status. Once information is loaded into the system for a given species of ant, the ant is given a sort of ID card which lists all of its traits. This database has the potential for use to make comparisons among a variety of ecologically important traits, and to examine trait variation across geographic distributions (it could therefore be useful in assessing the spread of invasive ant species). One might worry that simply checking off check boxes next to certain traits could potentially delimit the value of comparison of characteristics due to ambiguous definitions of the particular traits used in the database. For example, Ant Profiler lists tree/canopy, leaf litter, ground, twigs and logs, underground, nomad, and ubiquitous as possible nesting types for ants. However, some ant species such as certain Myrmica ants have been found to nest in snail shells and this does not fit nicely into any of these categories. However, the database could still serve as an important research tool and possibly be used to identify areas where ambiguous definitions might hinder analysis of trait distributions. Furthermore, research on other organisms could stand to gain much from a database such as this one, where multiple characteristics of the organism and natural history are all recorded in one place in a digestible format. This database is clearly just in its beginning stages and needs a lot of work before it can become a valuable research tool but one can hope that with time the site will be able to gain enough contributors to make the site viable.

There were also a number of interesting talks that weren’t about ants. For instance, May Berenbaum, a professor and head of the Department of Entomology at the University of Illinois at Urbana-Champaign (UI) gave a talk about “What students learn through engagement in entomological entertainment-related activities”. Her talk focused on the Insect Fear Film Festival held at UI since 1984. During this festival, they show two or three feature-length films such as the films “Them” and “Invasion of the Bee Girls” interspersed with animated shorts, each focusing on a different theme. As May puts it in her summary of the history of the festival “When we began, Ronald Reagan was in office, materialism was rampant, and insect movies were terrible; today, there’s a democratic president in Washington, environmental awareness and volunteerism are more fashionable, and insect movies are still terrible; it’s nice to know that there are some things in life to count on”. The festival is also interspersed with opportunities for the public to see and handle live specimens, enjoy deep-fried appetizers, get the insect fear film festival annual T-shirt (which has gained fame by itself), and get more accurate answers to questions about insects than what’s depicted in the films. Students are heavily involved in this festival and as a result have a number of opportunities to engage with not just the university community but the general public as well. My favorite example she gave occurred at the 1999 mosquito film festival where students organized the thematically relevant blood-drive. It has always been my constant struggle to convince certain members of my family of the importance of insects and that we need not always just squish them because it’s somehow politically correct to hate them. Her presentation and other outreach related talks I attended gave me many new ideas for current efforts I am pursuing on my campus and more fuel to continue my attempt at changing these views or at least with multiple new ideas to “brain wash” my baby sister…

Through talks such as these, I had multiple opportunities to speak with distinguished scientists, even though I had never met some of them before. This opportunity to speak with experienced professors and current graduate students not only allowed me to expand my entomological and ecological knowledge but to obtain some great advice on dealing with the hazards of research, the process of moving forward toward getting a PhD, where good potential future labs are that I might want to join to obtain my PhD, and, well, good advice on how to live life as a responsible citizen. Even if the undergraduate student does not wish to go on to graduate school, much can still be gained from attendance and I left the meeting inspired and ready to take action.

¹Hoffmann, B. (2011) Biodiversity and Conservation 20:3267-3278.

 Introducing the Real Green Man

Humanity currently faces significant environmental challenges due to climate change, habitat destruction, overexploitation of natural resources, and biodiversity loss. These challenges are related to human population size, resource use, and waste production. Given that our population continues to grow and our per capita ecological footprint gets ever larger, there’s a lot of work for us to do. Is there any chance that we can make our society sustainable? Can we create a world in which we live happy lives in a vibrant society without degrading our natural systems? The short answer is YES: good descriptions of the policies that we need to enact can be found in recent books by Thomas Friedman and Paul Gilding. But we need passionate buy-in to create major societal restructuring needed to become sustainable. We need a war effort focused on reducing our environmental impact.

So how do we increase our collective appreciation of these dire circumstances? One way would be to target the message to demographics that show the least concern. If we can begin a dialogue with the most skeptical among us, than it should be easier to build a broad consensus that will actually lead to action.

So what’s a demographic to target? What is a group that shows less concern about environmental issues and can be easily targeted with “educational information”?

The most obvious answer is MEN. A Gallup poll of Americans from 2006 assessed feelings about environmentalism; it found that 68% of woman were either “sympathetic to or active in the environmental movement”, while only 56% of men were. But does it have to be this way? Are the goals of environmentalism in conflict with the goals of the average man? Maybe we just need to find some common ground.

And I think there is a lot of common ground. There are clearly aspects of the stereotypical male lifestyle that can help galvanize environmentalism. So here’s a first attempt to put together a list of the traits for what I’m calling “Real Green Men”. I’m sure this list is incomplete and I’d love to get some more suggestions. But here’s what I came up with:

1. Real Green Men don’t “shop ‘til they drop”. Social pressures sometimes force a real man to spend a lot at the mall. Women report enjoying shopping more so than men and are more involved in shopping activities (Fischer & Arnold, 1990, Journal of Consumer Research, 17, 333-344). For example, 78% of respondents to a survey about Christmas shopping (Laroche et al. 2000, Canadian Journal of Administrative Sciences, 17, 1-19) and 73% of respondents to a survey about food shopping were female (International Mass Retail Association, 1993). If pressured to go shopping or to allocate resources to shopping, a Real Green Man can say “the United States emits more greenhouse gases than any other country except China, and we emit more than 4 times the amount of greenhouse gases per capita than do the Chinese. Consumerism in the US is a big contributor to these emissions. And we’re in trouble – in 2010, the amount of greenhouse gases emitted globally exceeded the International Panel on Climate Change’s worst case scenario model. The mall is not a place for a Real Green Man or his kin.”
2. Real Green Men don’t obsess about their appearance. Social pressures sometimes force real men to wear clean, wrinkle-free outfits. Social pressures force real men to take daily showers and shave. A Real Green Man can stand up to those pressures. He can say “more than one out of six people on the planet lack access to safe drinking water, and more than one out of three lack adequate sanitation. In the US, the average individual daily use of water is ~159 gallons, while more than half the world’s population lives on less than 25 gallons per day! Wearing my favorite shirt day after day serves a greater purpose.”
3. Real Green Men don’t complain about physical discomforts. Social pressures sometimes force real men to turn up the thermostat during the winter. But real men are tough, and they view physical stress as a challenge. Armed with the knowledge that raising your thermostat down by two degrees F in winter and up by two degrees F in summer can decrease your carbon emissions by 2,000 pounds per year, a Real Green Man can display his manliness with bold displays of thermoregulation.
4. Real Green Men make things from scratch. The centers of all of the world’s oceans are filled with particles of plastic, with devastating consequences for the marine ecosystem. There are many ecological costs associated with plastic waste, including the fact that they can release hormone-mimicking substances that may alter sexual development and increase cancer risk in humans and other animals (for a case study, see Nancy Langston (2010) Toxic Bodies). Real men know how to build things, to fix things, and to grow things. Real Green Men know that making things themselves also means that they don’t have to buy everything that comes in ultra-durable plastic wrapping.
5. Real Green Men aren’t lazy. At some point, men became associated with inventions that make life easier – leaf blowers, snow blowers, riding mowers. But real men don’t use these tools. They use their massive shoulders and thick forearms. They’d rather grunt and grown with a rake or a shovel than use the tools of decadence. According to the US Environmental Protection Agency, one gas lawn mower spews 88 lbs. of carbon dioxide and 34 lbs. of other pollutants into the air every year. A new gas mower produces as much CO₂ per hour as 11 cars; older versions are even worse. A Real Green Man not only knows the value of using his brawn, and he also knows the impact he can have on the environment.
6. Real Green Men eat meat (but only if it’s an invasive or pest species). What could be manlier than bringing down a wild animal and using the meat to provision one’s family and friends? Even Hollywood knows: Real men hunt. But what about Real Green Men? There are certainly ecological reasons for a Real Green Man to be a vegetarian. Given that only about 10% of the energy at one trophic level (e.g., plants) is transferred up to the next trophic level (i.e., herbivores), eating lower on the food chain as a vegetarian is much more efficient than eating as a carnivore. But the primal urges are strong in the Real Green Man, and he yearns to track, capture, and overcome his prey. And he likes the taste of meat. Must he satisfy himself with attacks on mock duck? No. A Real Green Man can hunt and have a positive effect on his environment at the same time, as long as he targets invasive and pest species. Invasive species are having an increasingly large effect on native ecosystems – their spread is largely due to human commerce and other economic activities. One idea for controlling invasive species that is getting attention is to promote them as dinner items. For example, the lionfish – an invasive species that is having a devastating effect on reef-dwelling fish communities in many tropical areas – apparently tastes delicious! The Real Green Man can even hunt deer – a traditional favorite of many real men hunters – because deer populations are well above long-term average abundances in many areas. Of course, the Real Green Man is well informed, and knows how the specifics of his actions affect the environment. For example, trapping lionfish can ensnare native fish instead, so spearfishing is the right strategy for the Real Green Man. And a Real Green Man would not support managing an ecosystem to support his hunting needs – a Real Green Man doesn’t need a handout.

Does the Real Green Man have a future? I hope so, because we need him for the environmental war effort. Greening up may also do wonders for the traditional real man by giving him a way to lead his community to a more promising future.

Population ecology and the coming of the zombie apocalypse

In 300 A.D there were 50-60 million humans, by 1804 there were 1 billion, and last week, the UN reported that there are now 7 billion of us. And more are coming. Given that the planet has a limited resource base, the human population cannot grow forever. Demographers describe constraints on population growth with a metaphor, the carrying capacity, which is the maximum population size that a habitat can support indefinitely. Population growth rate decreases to 0 as the population size approaches the carrying capacity. The processes that bring about this decrease in population growth rate are called negative density-dependent factors. These factors include the crappy aspects of civilization – food and shelter scarcity, violence among individuals, higher risk of disease, waste accumulation – as well as behaviors that reduce birth rates. As of now, resource use per person is still increasing as the global economy continues to grow (albeit unevenly). But it’s impossible for the human population to increase in size indefinitely – even if technology increases resource use efficiency. Population growth rates will decrease, and this decrease will be due to negative density-dependent factors. Hopefully, we’ll figure out a way to reduce birth rates and resource use rates without mayhem. I’m not optimistic.

And I don’t think I’m alone in this view. My feeling is that people are getting a stronger sense that human impacts on ecosystems are becoming increasingly severe and show no signs of abating. These impacts will cause greater and greater challenges for us, but how exactly they will affect population growth and resource use is unclear. Will there be gradual modifications in lifestyles until we emerge as a globally sustainable society? Or will there be catastrophic transitions that massively restructure society? I imagine that most people have a general sense that the world is crowded, it’s getting more crowded, and this trend can’t continue forever. They feel that change is coming, but they are uncertain about what that change will look like.

So what’s going to happen? One option that is getting a lot of attention is a zombie apocalypse. The idea of zombies originates from the depiction in Haitian culture of bringing corpses back to life using witchcraft. In modern culture, the zombie concept was popularized by the classic 1968 film “Night of the Living Dead”, in which the dead become re-animated and then seek out the living as food. Although the zombie concept has remained a part of American culture since that time, its prevalence has exploded over the last few years. A quick search for “zombies” on amazon.com brings up over 30 titles (!) published since 2006, including “The Zombie Survival Guide: How to Live Like a King After the Outbreak” by Etienne DeForest, “Pride and Prejudice and Zombies: The Classic Regency Romance – Now with Ultraviolent Zombie Mayhem!” by Jane Austen and Seth Grahame-Smith, and one that I highly recommend, “World War Z: An Oral History of the Zombie War” by Max Brooks. I’m currently reading “Zone One” by Colson Whitehead, about a military unit assigned to “eliminate” any remaining zombies in New York City about 2 years after a zombie apocalypse. I started reading this book because of all of the critical acclaim it’s received; the New York Times described it as “a cool, thoughtful and, for all its ludic violence, strangely tender novel, a celebration of modernity and a pre-emptive wake for its demise.” But I’m still trying to figure out why the zombie genre has become so popular, and I wonder if it has to do with global ecology.

Zombieism is a strong negative density-dependent factor. It’s interesting that the cause of zombieism in “Night of the Living Dead” was the release of radiation from a satellite. That was 1968 – the height of the space age and the threat from the great Communist menace. In today’s literature, zombieism is a combination of cannibalism (zombies eat humans) and an emerging infectious disease (getting bit by a zombie gives you the zombie plague, which kills you (within hours or days) and then re-animates you (within minutes) hungry for human flesh). In the real world, cannibalism occurs in a variety of species and often becomes more prevalent at higher population densities. My favorite example of cannibalism is from the spadefoot toad genus Spea, a group of desert-dwellers that inhabit rain-filled pools. Spea tadpoles often have to mature rapidly to reach adulthood before ephemeral ponds dry up. Conditions indicating high tadpole densities trigger the development of a cannibalistic Infectious disease transmission is more likely when population density and contact among members of the same species are high. Cannibalism and infectious disease can be interconnected. For example, tiger salamanders are more likely to develop a serious hemorrhagic disease when they eat infected members of their own species. In humans, observations of a Papua New Guinea tribe have shown that eating human brains increases the risk of catching the deadly disease kuru. 

Zombieism is an even tighter connection between cannibalism and infection disease. For the zombie disease, the plague actually leads to cannibalistic behavior. In fact, it seems to create a singular and insatiable drive for the flesh of the living. Every successful attack spreads the disease, and the positive feedback can quickly lead to an apocalypse. (The dynamics of this disease have actually been modeled in a book on host-disease interactions). The only hope for the living is to create a well-protected refuge and hone your anti-zombie defensive skills (you can kill a zombie by destroying its brain).morphology, and the ensuing carnage leads to a reduction in population size. Infectious disease transmission is more likely when population density and contact among members of the same species are high. Cannibalism and infectious disease can be interconnected. For example, tiger salamanders are more likely to develop a serious hemorrhagic disease when they eat infected members of their own species. In humans, observations of a Papua New Guinea tribe have shown that eating human brains increases the risk of catching the deadly disease kuru.

So how is the recent explosion (epidemic?) of zombie literature related to today’s population ecology? Maybe zombie literature describes a type of worst-case scenario as the world gets more crowded and our natural support systems become more degraded. Imagining worst-case scenarios may prepare us psychologically when (if?) real chaos actually emerges. And even though the destruction brought about by a zombie apocalypse is horrific (even parts of the campy “Night of the Living Dead” are hard to watch), the end result is a massively reduced population size and a lot of civilization’s infrastructure left intact. That scenario will have broad appeal. Survivors of the zombie apocalypse won’t need to think about the ecological consequences of their actions – they’ll be able to use a leaf blower while sitting in their Hummer without having to think about what some crazy environmentalist has to say about it.Life will be good. So it might be time to hone your skills as a writer of zombie literature; that fantasy may become even more appealing for us in the future as the impact of climate change and habitat destruction become even more acute. Or, better yet, learn how to slay zombies.   

Humanity’s future is bright, or maybe it’s not

The United Nations last week reported that the earth’s population has now reached 7 billion. The 7 billionth person doesn’t change our social or ecological conditions in any fundamental way, but the milestone provides an opportunity for reflection on broad trends. What is in store for this mass of humanity? Will more creative minds give us a better opportunity to develop technologies that enhance our quality of life? Or is the impact on the global ecosystem of so many humans moving us toward a catastrophic collapse?

I’ve been struck recently by how variable the answers to these questions are, even among experts in global development and human demography. In particular, two recent books on humanity’s future that have received a lot of attention, “The Great Disruption” by Paul Gilding and “Getting Better” by Charles Kenney, paint such distinct pictures of our current conditions and challenges that I thought it would be worthwhile to contrast their assumptions and interpretations.

Gilding’s title refers to the massive societal reorganization that he argues will inevitably occur as a result of climate change and other human impacts on global ecosystems. He points to evidence that humans long ago passed the planet’s limits to supply our resource needs and to absorb our waste. One area of emphasis is work by the Global Footprint Network, which estimates the amount of natural resources needed to maintain our economy and lifestyle. The estimates are frightening: humans overshot the earth’s carrying capacity in 1985; in 2009, we needed 1.4 planets’ worth of ecological services to support our activities (the short-term overshoot is possible because of reliance on fossil fuels and other non-renewable resources). He also describes the evidence for the connection between climate change and human activities, identifies the likely scale of the near-term problems associated with climate change, and states that there is essentially no disagreement among scientists about these general conclusions.

The main thrust of Gilding’s presentation is that because we are already significantly past the earth’s carrying capacity and the pressure of humans on the global ecosystem is only going to increase, the die has already been cast and we are headed for calamity. “This means that assumptions we make about global society – that we will bring the poor out of poverty, that we will carry on creating jobs, food, and basic needs for the more than two billion new global citizens and the existing seven billion or so, that we in the West will continue to increase our financial and material standard of living, that the world, despite conflicts here and there, will carry on in relative stability – are a grand delusion.” Instead, he predicts massive turmoil leading to a major reorganization of society focused on sustainability and a more equitable distribution of resources across the global population. What’s inspiring about Gilding’s argument is that he argues convincingly that the knowledge and the resources are available to guide a societal transformation to sustainability. We know what to do – implement cap-and-trade systems for dealing with emissions of carbon and other pollutants, massively invest in renewable energies, start government programs to reduce consumer consumption in developed countries, etc. – and he argues that when people feel the full force of the Great Disruption, they will support these measures with the same passion and verve that populations in the past have shown when facing existential threats in war.

Charles Kenny’s book, Getting Better, provides a much more optimistic view about the state of the world. He argues convincingly that the collective well being of the human population has never been better. Almost every per capita indicator of human welfare – income, child survival rates, longevity, infectious disease prevention, reductions in violence, gender equality, adult literacy rates, democratization – have all increased substantially across the globe over the last 50 years or more. Moreover, the overall pattern in these measures has been toward convergence among countries – quality-of-life measures in poorer countries are increasing faster than in richer countries. He shows that even in areas of the world in which per capita income and gross domestic product (GDP) have stagnated over the last 50 years (as in much of sub-Saharan Africa), other quality of life measures have significantly improved. For example, in 12 countries that had a decrease in GDP from 1960 to 2005, life expectancy increased by an average of 10 years, and adult literacy rates closed to doubled on average. His main conclusion is that much of the improvements that we refer to as “development” can be brought about through the creation, spread, and application of ideas and technologies for improving the quality of life that do not require an increase in income and its associated ecological costs.

I found the core message in Kenney’s book noteworthy and inspiring. It’s too easy to lose sight of the tremendous improvements in the general quality of human life over the last century given the current inequities, calamities, and environmental challenges. Things are generally better, and general improvements can lead to further improvements as people begin to expect health, education, and equal opportunities. However, he largely sidesteps the issues of resource depletion and climate change. These issues are viewed as another challenge that the global development community can take on, rather than as the inevitable cause of catastrophe that will radically transform society.

These very different perspectives on the future of the global society made me think of an ecology talk I recently attended by Mike Pace from the University of Virginia. He and his colleagues provided evidence that an increase in the variability of key features of an ecosystem (in this case, the amount of chlorophyll a (a measure of productivity) in a lake ecosystem) was an indicator of an upcoming “regime shift”, a substantial and largely irreversible change in the state of an ecosystem. So are highly divergent views on the global condition the sign of a pending global “regime shift”? Let’s hope not, but it’s certainly time to get to work.

Why I like Biology

(Note: I wrote the essay below for a popular science blog. It didn’t get published, but I can publish it here and I hope it’ll get the ball rolling with this blog)

I like biology because it has helped me understand who I am and how I fit into the world around me. As an undergraduate student, I struggled to understand why conflict and suffering seemed to be an inevitable aspect of the human experience. I searched for answers as a religious studies major at the University of North Carolina, but I never found anything deeply satisfying until I stumbled across E.O. Wilson’s “Sociobiology”, a wonderful book that describes social behavior from microbes to mammals. By the time I finished the famous final chapter, “Man: From sociobiology to sociology”, I was convinced that evolutionary biology had enormous potential to help explain human nature. Over time, I found that core evolutionary theory about social interactions – kin selection, parent-offspring conflict theory, sexual selection – provided explanations for my motivations that were far more satisfying than anything else I had been exposed to. Now, as a researcher and professor studying behavior, I have learned that ideas about the evolutionary underpinnings of human behavior are novel, interesting, and often challenging to students trying to figure out meaning and purpose in their world. Studies from the natural world describing complex behavior help students feel more connected to nature. One of my favorites is a study by Jeffrey Hoover and Scott Robinson that describes how cowbirds, which lay eggs in the nests of songbirds, use mafia-like behavior to ensure that the parasitized songbirds rear rather than destroy the cowbird eggs (Hoover and Robinson 2007). At the same time, studies of the adaptive significance of modern human behavior, for example the studies by Randy Thornhill, Steven Gangestad and others showing how odor attractiveness is sub-consciously associated with body symmetry (e.g., Thornhill and Gangestad 1999), or the study by Melissa Bateson and colleagues showing how the presence of a photograph of human eyes increases contributions to an honesty box (Bateson et al. 2006) often give students new insight into the motives underlying their social interactions. Given the complexities of modern life and the incredible challenges facing the global population, I hope that self-awareness gained through biology will help us understand causes and find remedies for our social ills.

Bateson M, Nettle D, Roberts G (2006) Cues of being watched enhance cooperation in a real-world setting. Biology Letters, 2, 412–414.

Hoover JP, Robinson SK (2007) Retaliatory mafia behavior by a parasitic cowbird favors host acceptance of parasitic eggs. Proceedings of the National Academy of Sciences of the United States of America, 104, 4479-4483.

Thornhill, R., & Gangestad, S. W. (1999). The scent of symmetry: A human pheromone that signals fitness? Evolution and Human Behavior, 20, 175-201.

Our New Blog!

The field of Biology has relevance for many of our major societal challenges and opportunities. Faculty in the Biology Department at the University of St. Thomas conduct research and teach classes that address societal issues, but we are also interested in generating a dialogue and sharing information with a broad community. The aim of this blog is to give department members an opportunity to share  information about their research, their teaching, their philosophy, or their opinions on recent biology-related news. We encourage comments on all posts. If guests (e.g., current students, department alums, other visitors) would like to post an entry, you can contact adam kay (adkay@stthomas.edu). Please include the phrase “Biophilia Blog entry” in the title of the email.