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Gavrilets Receives Army Research Grants

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Sergey Gavrilets, a distinguished professor in the Department of Ecology and Evolutionary Biology, has received more than $1.1 million in grants from the Army Research Office for study into societal resilience using evolutionary models and theories of revolution.

Gavrilet’s research is funded by the Department of Defense’s Minerva Program, which is dedicated to predicting future socio-political crises in the world and societies’ resilience to various political, economic, environmental, and health-related shocks.

“I work with mathematical models to develop a theory that hopefully will be useful to predict or identify certain problems or uncover gaps in our knowledge,” Gavrilets said. “I used to work a lot in biology and biological evolution, but lately I’ve shifted towards social and cultural evolution and behavior.”  

By using new and improved modeling tools, analysts will be able to assess political stability risks, improving predictions and explanations for societal unrest.

“The reason why we want to do this is because life is getting pretty complicated, especially over the last 10 to 20 years,” he said. “Conflicts are popping up in different places and usually come completely unexpected. Naturally, everyone wants to understand them better and hopefully predict them.”

Gavrilet’s research will also yield theoretical and modeling approaches with applications in fundamental sciences such as psychology, anthropology, and evolutionary biology.

–By Kelly Alley

The University of Tennessee wishes to acknowledge Lisa Troyer at the Army Research Office for supporting these projects.

Kivlin Coauthors Article on Fungal Aerobiota

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Stephanie KivlinStephanie Kivlin, an assistant professor of ecology and evolutionary biology, coauthored a paper titled “Fungal aerobiota are not affected by time nor environment over a 13-y time series at the Mauna Loa Observatory,” published in the journal Proceedings of the National Academy of Sciences.

Researchers used 13 years of collected air samples from Mauna Loa Observatory on Hawaii Island to determine if local or global environmental factors influence fungi composition.

“One of the big questions in microbial ecology is trying to figure out how microbes disperse around the world and if they can disperse everywhere,” Kivlin said.

Kivlin and other researchers from the University of Hawaii initially genetically sequenced fungal spores and studied their traits, such as size and shape, before discovering the role wind patterns play in fungal spore dispersal.

“What we found was that we could trace back wind patterns to try to understand where the wind was coming from that deposited the fungal spores on the filters,” Kivlin said. “We saw some that were coming from Asia, bringing fungi that are never found in Hawaii. The wind patterns are really what’s blowing the fungi around.”

The researchers also discovered that some airborne fungal spores are still viable after traveling long distances.

“Because we found a couple of fungi that were dispersing all the way across the Pacific Ocean, we need to really consider how far fungi can go and what that means for dispersal of new pathogens into new areas,” Kivlin said. “We need to have better theory about how often those dispersal events occur, which fungi are coming, and if they are beneficial or harmful.”

Coauthors on the paper include Laura Tipton, Anthony Amend, and Nicole Hyson from the University of Hawaii at Manoa, Erin Datlof from the University of Hawaii at Hilo, Geoffrey Zahn from Utah Valley University, and Patrick Sheridan from the National Oceanic and Atmospheric Administration’s Global Monitoring Division.

By Kelly Alley

Faculty Honored at College Awards Banquet

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The 2019 College of Arts and Sciences Faculty Awards banquet took place Thursday, December 5 at the Holiday Inn Downtown. From Diversity Leadership to awards in research, advising, and teaching, the annual awards banquet honors faculty excellence in all areas of the college mission.

Elizabeth Derryberry, Charlie Kwit, and Beth Schussler received awards for their work in the Department of Ecology and Evolutionary Biology.

“As we recognize particularly outstanding faculty this evening, I want to thank all of our faculty in the college, individually and collectively, for everything you do— your teaching, research, service on college and university committees, thesis committees, and tenure and promotion committees, and service to the public through community engagement,” said Theresa Lee, dean of the college and emcee for the awards ceremony. “A college can be no greater or stronger than its faculty and the College of Arts and Sciences is a college of excellence because each of you has a passion for our profession and you work selflessly to make our students, departments and university the best they can be.”

derryberry

Elizabeth Derryberry, associate professor, received a Mid-Career Award for Research and Creative Achievement. Derryberry’s research focuses on passerine bird evolution and bird songs – important topics that are notoriously difficult to study. Her exciting project on the effects of human-mediated noise in urban environments on bird song demonstrate both changes in song parameters in response to noise and consequences for ecosystem fitness. Derryberry is the author of more than 50 highly cited papers and an associate editor for two prestigious journals: Evolution and Journal of Animal Behavior. Her work is top-notch, broad-thinking, impactful science at its best. She is an outstanding student mentor and passionate about her outreach to increase opportunities for girls and women in science.

kwit

Charlie Kwit, professor and joint faculty in EEB and the Department of Forestry, Wildlife, and Fisheries in the Herbert College of Agriculture, received the Academic Outreach Award for Teaching. His work to promote natural history knowledge in the Southeast exemplifies academic outreach in teaching. This year, he received a grant to increase HBCU representation to the Southeastern Chapter of the Ecological Society of America and support students engaged in the work of the Society. He also organized a session at the annual ESA meeting that spotlighted the biodiversity of the Southeast and the challenges we face in maintaining that rich biological heritage. Kwit also fosters UT students in outreach through clubs and courses. Students in his class experience the very best of what is intended as part of the new Experience Learning efforts. They see the utility of what they are learning, enriching their engagement with the material, while also helping to build relationships between UT and the community that strengthen the institution.

schussler

Beth Schussler, professor, received the James R. and Nell W. Cunningham Teaching Award, the college’s highest teaching honor. There are no specific requirements listed for the award, but there are some things that are typical of the winners. One, excellence in the classroom. Schussler is highly praised by students and peers for her work in some of the more demanding biology courses. Two, contributions to excellence in others. Schussler supervised the lecturers and GTAs in the general biology courses, and helped train the GTAs, which came from all three of the departments in the Division of Biology. Finally, contributions to teaching beyond their courses and department. Schussler has organized workshops on teaching for STEM departments, and continues to be involved with nation-wide efforts and grants helping to improve biology and STEM instruction.

Congratulations to our Department of Ecology and Evolutionary Biology faculty award winners.

Gaoue Coauthors Article about Medicinal Jungle Plants

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Ourou Gaoue, an assistant professor of ecology and evolutionary biology, coauthored a paper titled “Non-random medicinal plants selection in the Kichwa community of the Ecuadorian Amazon,” published in the Journal of Ethnopharmacology.

Researchers analyzed data collected on indigenous people’s uses of non-random medicinal jungle plants at the local level, rather than at the national level. This is the first time a village-level study has taken place, better ensuring the consistency of plant availability in certain areas.

“When people are doing this study, they are usually doing it at the national scale,” Gaoue said. “If you’re doing the analysis at the national level, you are overestimating the number of plants from which the indigenous people actually find that have medicine.”

The study is also one of the most diverse in research of non-random medicinal plant selection, analyzing gender, age, and exposure to outside influences, such as ecotourism projects, to determine overuse and underuse of medicinal plants in jungle communities.

“Village level analysis provides a different result than at the national level,” Gaoue said. “A plant is not medicine for everyone. Men and women know different kinds of plants. An older person will see a plant with medicine in it that a younger person will not see. People who are educated would not see medicine in a plant that someone in a rural area would be able to see.”

Other authors on the paper include Daniela Robles Arias of Florida Atlantic University, Daniela Cevallos of Pontificia Universidad Católica del Ecuador, Maria Fadiman of the University of Parakou, and Tobin Hindle of the University of Johanesburg.

-By Kelly Alley

Budke Publishes Paper on Spore Dispersal of Fern

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Jessica Budke, an assistant professor of ecology and evolutionary biology and director of UT’s Herbarium, published a paper titled “Evolution of Perine Morphology in the Thelypteridaceae” in the International Journal of Plant Sciences, that looks at the dispersal of fern spores.

Researchers focused their study on Thelypteridaceae, a family of ferns that includes more than 1,000 species. Their research focused on spore ornamentation, or shapes and structural characteristics of the outside of the spores.

Researchers then used different spores from across the family to better understand relationships between the species, using a technique called ancestral character state reconstruction.

“We used a lot of molecular data to build a phylogenetic tree, and then mapped on the spore characteristics onto the tree,” Budke said. “By mapping them on the tree, we can look at the evolution of those features.”

The study used resources like the UT Herbarium, a repository of native and naturalized plants and fungi of Tennessee, for dried samples of previously collected ferns.

“We have more than 600,000 plant specimens on campus,” she said. “It saves time and money and resources because you’re not having to run around collecting everything.”

Other coauthors on the paper include University of Connecticut post-doctoral research assistant Nikisha Patel, University of Vermont graduate student Susan Fawcett, and University of Vermont research assistant professor Michael Sundue.

-By Kelly Alley

Underground fungal relationships key to thriving plants

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Stephanie Kivlin

For a plant to thrive, it needs the help of a friendly fungus–preferably one that will dig its way deep into the cells of the plant’s roots.

Plants live in symbiosis with root-associated, or mycorrhizal, fungi. The fungi provide up to 80 percent of the nutrients and water a plant needs to grow, and the plants produce up to 30 percent of the photosynthate–a food substance made through photosynthesis–that the fungi need.

There are two main types of mycorrhizal fungi – arbuscular and ectomycorrhizal. An arbuscular mycorrhiza penetrates the cortical cells of the roots of a plant. Ectomycorrhizal fungi do not penetrate the plant’s cell walls, instead forming a netlike structure around the plant root.

A new paper published in the Proceedings of the National Academy of Sciences and co-authored by ecologist Stephanie Kivlin, an assistant professor at the University of Tennessee, Knoxville, shows that arbuscular mycorrhizal fungi are especially helpful to the plants they colonize.

“Mycorrhizal fungal associations below the ground are one of the largest influences on plant tissue nutrient concentrations,” said Kivlin. “To optimize plant nutrition, we need to incorporate mycorrhizal associations into our agricultural and management frameworks.”

Arbuscular mycorrhizal fungi increase plant nutrient concentrations in plant leaves, litter, and roots more than ectomycorrhizal fungi. The type of root-associated fungi present has more influence on a plant’s nutrient levels than plant leaf traits or plant associations with nitrogen-fixing bacteria.

Kivlin’s co-authors are Colin Averill from ETH Zürich, Jennifer M. Bhatnagar and Michael C. Dietze from Boston University, and William D. Pearse from Utah State University.

The study analyzed more than 17,000 trait observations from nearly 3,000 woody plant species in six categories that demonstrate how readily the plant uses nutrients: the nitrogen and phosphorous concentrations in green leaves, senescent leaves–leaves that are about to fall off or have recently fallen off–and roots. It looks at how mycorrhizal effects vary across environments, doing similar analyses in boreal, temperate, and tropical latitudinal zones.

The Kivlin Lab studies the effects of global change on the distributions, function, and ecosystem consequences of plant mycorrhizal fungal associations worldwide.

“The next steps are to understand if there is variation in nutrient acquisition among fungal species within each mycorrhizal group and how soil nutrient concentrations may interact to influence plant nutrient concentrations with global change,” Kivlin said.

Derryberry Recognized in Women of Ornithology Article

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Elizabeth Derryberry, a professor of ecology and evolutionary biology, received recognition in a timeline of important female ornithologists in a Cornell Lab of Ornithology article, focusing on the achievements of female ornithologists and their role in determining the causes of evolutionary advancements in birds.

Part of Derryberry’s research focuses on the how bird songs are shaped by urban environments.

“One of the things I’ve been most interested in over the last five years is looking at how urban noise affects bird song,” she said.

Through research in San Francisco of urban and coastal white-crowned sparrows, Derryberry and other researchers determined that the volume and frequency of a song is correlated to the birds’ environment. As noise frequency increases in a city or along the coast, so does the birds’ songs. This creates loud, high pitched notes in shorter intervals, as compared to songs from birds living in low noise frequency environments.

“We found that within a population, males vary their vocalizations in their songs based on how loud it is on their territory,” said Derryberry. “As traffic noise increases and city noise levels increasing, we are seeing a shift up in frequency.”

The article provides a recognition of women ornithologists and highlights the importance their research has had. “I think women have been really impactful in ornithology for a long time,” she said. “It’s really just a matter of recognition. It’s great to see those sorts of efforts.”

Invisible Organisms with an Enormous Impact

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Understanding the distributions and functions of microscopic fungi and bacteria is what drives new Assistant Professor Stephanie Kivlin’s research.

Stephanie Kivlin“Microbes can sometimes get a bad reputation, causing disease, food spoilage, etc.,” Kivlin says. “But, people are often surprised to learn that most microorganisms are beneficial for humans; increasing crop yields, purifying water, and recycling nutrients from dead plants back into soils.”

Because there are more than 1,000,000,000 microorganisms in a scoop of soil, determining exactly where, when, and how microbes perform these beneficial functions is still an open line of research. These questions motivated Kivlin to follow a career in microbial ecology after being trained as a microbiologist. She has since pursued research to connect the function of these tiny organisms (< 0.01mm) to whole ecosystem scale resource dynamics.

Kivlin’s research occurs in locations near and far from Knoxville. She spends her summers assessing microbial response to the 2016 Chimney Tops 2 fire in the Great Smoky Mountains National Park and elevational patterns of microorganisms and the soil resources they affect in the western Colorado Rockies at the Rocky Mountain Biological Laboratory. The rest of year, she models microbial biogeography and ecosystem resource cycling at regional to global scales.

Students participate in a long-term warming experiment at the RMBL collecting fungal endophytes from grass leaves for metabolic analysis.

Students participate in a long-term warming experiment at the RMBL collecting fungal endophytes from grass leaves for metabolic analysis.

Kivlin is especially thrilled to be joining the UT EEB faculty. “I have always valued and encouraged collaborative science. The unique opportunity to collaborate with plant and soil ecologists, mycologists and spatial ecologists in the UT EEB department combined with associations with ecosystem modelers at the Oak Ridge National Lab is the perfect fit for my research program.”

Kivlin’s field site view from Rosy Point, Gothic, Colorado.

Kivlin’s field site view from Rosy Point, Gothic, Colorado.

Kivlin is no stranger to the excellent microbial and ecosystem ecology group already established in the department. To start her lab, Kivlin brought on recent UT EEB PhD graduates Jessica Moore and Leigh Moorhead, with expertise in ecosystem modeling and response to disturbance, as postdoctoral researchers. Moore and Moorhead took advantage of the UT-ORNL connection by conducting their PhD research at ORNL.

“The unique opportunity to collaborate with leading ecosystem experts at ORNL enticed me to select UT for graduate school, and I’m excited to further my ORNL collaborations throughout my post-doc,” Moore says.

“Ecosystem and microbial ecology have always been a strength of the UT EEB department, so I was exceptionally fortunate to attract two postdoctoral researchers whose graduate careers I had been tracking over the last five years,” Kivlin says. “We are all looking forward to building intra- and inter-departmental scientific synergies!”

The Geography of Ecology

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What’s the difference? How is it that a pest or pathogen can kill its host in one place but not another? Research Assistant Professor Christy Leppanen wants to know.

Leppanen is looking for differences that explain why an invasive insect, the hemlock woolly adelgid (Adelges tsugae or HWA), kills North American eastern hemlocks (Tsuga canadensis) and Carolina hemlocks (T. caroliniana), but not hemlocks from its native range in Asia.

Christy Leppanen“Simply speaking, I am interested in identifying mechanisms responsible for different outcomes when communities are considered the same,” Leppanen says. “For example, a particular insect pest or biocontrol agent kills its host plant in one location, but not another. We increase the likelihood of success and reduce the risk of negative non-target effects when management takes these mechanisms into account.”

Easier said than done. Including these considerations seems intuitive, but discerning differences in communities is challenging. Populations are influenced by direct and indirect interactions, such as with predators, competitors, pathogens, and microbial communities, or host resistance, all influenced by variation in nutrients, phenology, and climate.

“Difficulty transferring population control mechanisms from one location to another might reflect the fact that differences in these systems might not be inconsequential.”

For instance, in eastern North America, hemlock woolly adelgid (HWA) biocontrol using natural enemies translocated from HWA’s native range has not yet proven successful. HWA infests different hemlock species in its native range. Evidence suggests host resistance influences infestations, and while this does not preclude some role of natural enemies, vulnerability in eastern North American hemlocks might override possible population level control by natural enemies.

Leppanen comes from a multidisciplinary research, management, and regulatory background in environmental toxicology, conservation biology, and pest management. Her work with HWA falls within her larger interests to improve pest control, mitigate associated harmful non-target effects, and increase sustainable practices.

“The HWA problem embodies many challenges we face managing nature,” Leppanen says. “We have not confirmed which mechanisms control HWA populations in its native range, but specificity associated with effective biocontrol means its interactions and role in population control must be precisely understood. We sometimes feel pressured, however, to implement before we understand. Additionally, approaches sometimes counter one another; for example, chemical control that is often broad spectrum can have broad non-target impacts, even to natural enemies.”

Leppanen is confident scientists will find solutions.

“Collectively, we’ll keep at it. This is interesting and important work, with new tools and technologies and an enthusiastic and engaged group of participants.”

At UT, Leppanen teaches courses in environmental toxicology and invasion biology, the latter with Professor Daniel Simberloff. She is also the author of an award-winning mock scientific journal. The Bulletin of ZOMBIE Research (BOZR) is a collection of deadpan post-apocalyptic articles that uses popular culture to lure readers into learning about research and technical literature, dissolving barriers to accessing and understanding science.

Illustration by Steven Lee (graphiko.com)

Gross Receives SEC Award

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Professor Louis Gross was honored with the 2018 SEC Faculty Achievement Award this week.  The award recognizes professors from the 14 Southeastern Conference schools who have outstanding records in teaching and scholarship. Honorees from each university receive an honorarium and become their university’s nominee for SEC Professor of the Year, to be awarded later this spring.

The full press release can be viewed at news.utk.edu.