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Sheldon Receives NSF CAREER Award

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SheldonKimberly Sheldon, an assistant professor in the Department of Ecology and Evolutionary Biology (EEB), was awarded a highly-competitive Faculty Early Career Development (CAREER) Award from the National Science Foundation (NSF). The award is NSF’s most prestigious recognition for early-career faculty members and recognizes individuals “who have the potential to serve as academic role models in research and education and to lead advances in the mission of their department or organization.”

The multi-year, $1.3 million grant will support Sheldon’s project examining behavioral shifts of temperate and tropical dung beetles in response to temperature change. In addition, the grant will provide internships for UT undergraduate students and research opportunities for Native American high school students.

“Dung beetles remove and recycle waste and are thus both ecologically and economically valuable, but these beneficial insects may be in trouble,” Sheldon said. “Like all insects, dung beetle development and survival are impacted by temperature. Researchers predict that warmer temperatures will result in population declines and tropical insects, which make up the vast majority of biological diversity on Earth, may be particularly at risk.”

dung beetleInsects might compensate for temperature increases by shifting their behavior to use cooler microclimates within their environment. Sheldon’s research team will spend the next five years investigating how dung beetles in Tennessee and Ecuador respond to warmer and more variable temperatures and how that behavior impacts their offspring’s development and survival.

“We will expose tropical and temperate dung beetles to temperature changes using lab experiments and field manipulations,” Sheldon said. “After observing the dung beetles’ responses, we will build a model to predict impacts of temperature change on insect populations.”

This work fits into Sheldon’s overall research program aimed at understanding the processes leading to the distribution and abundance of organisms and applying this knowledge to predict the impacts of climate change on biological diversity.

As part of the award, Sheldon will lead STEM education initiatives for students from diverse backgrounds and perspectives. She will work with a collaborator from the Eastern Band of Cherokee Indians (EBCI) to support science programs for Native American high school students. Her lab will also host undergraduate interns with the goal of increasing STEM literacy through field-based inquiry.

“This type of hands-on experience can increase interest in STEM fields and help students gain confidence to pursue advanced degrees,” she said.

Sheldon, who joined the UT faculty in 2016, credits the backing she received from her colleagues and the college for her successful grant proposal.

“I was given the encouragement and freedom to pursue my research goals and develop the education program that led to the CAREER award,” Sheldon said. “I also have great collaborators in Ecuador and with the EBCI who have supported the research and education goals, and talented lab members who gathered some of the preliminary data that went into the proposal.”

Sheldon received her bachelor’s degree in natural resources from the University of Michigan and her PhD in zoology from the University of Washington before completing an NSF postdoctoral fellowship in biology. She received the 2020 Faculty Academic Outreach Research and Creative Activity Award from the UT College of Arts and Sciences.

Budke Receives NSF CAREER Award

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BudkeJessica Budke, an assistant professor in the Department of Ecology and Evolutionary Biology (EEB) and director of the UT Herbarium, received a highly-competitive Faculty Early Career Development (CAREER) Award from the National Science Foundation (NSF). This multi-year, $1.4 million grant will support Budke’s work on parent-offspring conflict in mosses.

“The conflict is a striking paradox where parents have to balance limited resources between investing in their offspring and reserving resources for their own survival and future reproduction,” Budke said. “Moss plants are an ideal system to study this conflict since their offspring remain physically attached and nutritionally dependent on the parent plant throughout their lifespan.”

mossesUsing field-collected plants and natural history specimens, Budke will use an innovative and integrated research approach that incorporates comparative analysis of function morphology, physiology, and evolution to explore and understand the processes that have led to diverse adaptations for regulating parental-offspring resource allocation across species.

During an engaging May-term course that will be offered multiple years at UT, students will be in the field, laboratory, and behind the scenes of natural history collections, such as the UT Herbarium, where field collections and specimen-based research will be essential components of the class.

“Undergraduate students will also have the opportunity to work with graduate students and postdocs and see the stages of an early-career scientist, which could get them excited about joining the lab and pursuing a career in science,” Budke said.

mosses2Budke and her students will use the experiences and data from the course to build educational modules and activities for UT programs at natural history museums and local public botanical gardens. They will host sessions about mosses and specimen research for students grades 3-12 and will build an educational module for the UT Biology in a Box program to engage kids with natural history collections and moss biology.

This research will lay the groundwork for future biodiversity studies in mosses and improve the body of knowledge and understanding of parent-offspring relationships broadly across plants.

“We are trying to think about this in terms of how plants live in the world,” Budke said. “Evolution can occur over long periods of time, but with this research, we are zooming in on a single generation to understand how parents influence their offspring, specifically how they provide the resources they need to survive, thrive, and produce the next generation of mosses.”

The CAREER award is NSF’s most prestigious accolade for early-career faculty members and recognizes individuals “who have the potential to serve as academic role models in research and education and to lead advances in the mission of their department or organization.”

UT students interested in research opportunities with this grant should contact Jessica Budke to learn more.

Why Are Some Mushrooms Poisonous?

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Poisonous or edible? Ekaterina Morozova/iStock via Getty Images Plus

Karen Hughes, University of Tennessee

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com.

Why are some mushrooms poisonous and some are not? – Alice T., age 11

You may have noticed that mushrooms pop up in your yard or in parks right after a rain but don’t last for long.

A mushroom is the above-ground part of a fungus. Most of the time, fungi live as threadlike structures called hyphae underground or in materials like wood. For fungi to reproduce, a mushroom must form above ground.

Some mushrooms are poisonous for the same reason some plants are poisonous – to protect themselves from being eaten so they can reproduce. Other mushrooms use the opposite strategy. They need animals to eat them in order to spread spores through poop. Still other mushrooms have completely different game plans.

Finger shaped fungi release spores that look like smoke.
The candlestick fungus, Xylaria hypoxylon, releases its spores. Jasius/Moment via Getty Images

Spreading spores

Mushrooms develop when the temperature is right and there is enough water. They usually consist of a cap and a stalk. On the underside of the cap, mushrooms produce spores that, like the seeds of plants, produce new fungi.

If you peek under a variety of mushroom caps, you will notice they are not all the same.

Some mushrooms have gills that look like a pleated sheet of paper. Some have pores that look like sponges. And some have toothlike structures. All of these surfaces produce spores. To create a new generation of fungi, spores need to get to new areas – and there are many fascinating ways mushrooms accomplish this.

For some mushrooms, spores simply fall from their caps and are carried to new homes by air currents.

A cluster of mushrooms glow in the dark.
The ghost fungus, Omphalotus nidiformis, at night in an Australian driveway. Louise Docker Sydney Australia/Moment via Getty Images

Other mushrooms attract insects by glowing at night. The glow from fungi in the woods at night can be very strong and is sometimes called foxfire. Insects, which are attracted to the light, inadvertently pick up spores as they investigate the glow and carry them elsewhere when they move on.

Some mushrooms never form an above-ground structure. Instead the mushroom stays underground and is eaten by squirrels and mice, which spread the spores by taking pieces back to their nests and by pooping. Such mushrooms are called truffles, and sometimes people will pay a lot of money for them.

A window of opportunity

Since mushrooms don’t last long, it’s important they spread their spores quickly. This is where poisons and toxins can come in.

Mushrooms are pretty tasty to snails, some insects, beetles, chipmunks, squirrels, deer and people. If an animal eats a mushroom, usually its spores are lost – unless they’re the type encased in a protective covering meant to be carried to a new neighborhood in poop.

Scientists have figured out that insects and snails avoid eating mushrooms that contain poison. Some mushroom poisons may make the eater only sick enough to avoid that species in the future, but some can be fatal.

A white gilled mushroom lies on its side in the grass.
A deadly poisonous mushroom, Amanita virosa. gailhampshire/Flickr, CC BY

There are many different mushroom poisons. One kind belongs to a group of very beautiful mushrooms, the amanitas, also called “destroying angels” because they are both pretty and deadly. Amanitas are often mistaken for mushrooms that can be eaten, and they cause several deaths worldwide each year.

People use some mushroom poisons in medicine. The poison of the ergot fungus, for example, was developed into a drug used to prevent migraine headaches.

Approximately 1%-2% of mushrooms are poisonous to humans. The common term for such a mushroom is a “toadstool,” but there is no easy way to distinguish a poisonous mushroom from one that is edible. So it’s not a good idea to eat mushrooms you find, because it’s hard to be sure whether they’re poisonous or not.

Many mushrooms are healthy and delicious. Just make sure you get them from a store or from someone who is a mushroom expert.

Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to CuriousKidsUS@theconversation.com. Please tell us your name, age and the city where you live.

And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.The Conversation

Karen Hughes, Professor of Mycology, University of Tennessee

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Tomato Production At Risk Due to Decrease in Buzz Pollinators

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tomatoesTomatoes are the heart of many backyard gardens. Tomato crops are also an important economic revenue in North America. The vegetable we all know as the “T” of a great summer BLT, however, may be in jeopardy due to a decline in its pollinator species because of climate change.

According to a study published in Ecological Applications, tomato production is at risk in the Eastern United States due to climate-induced decrease in the richness of buzz pollinators. Approximately 70 percent of the world’s crops depend on insect pollination for production. Climate change is already affecting the abundance of pollinators, but researchers with the National Institute for Mathematical and Biological Synthesis (NIMBioS) wanted to know how climate change impacts the pollination of specific crops.

Wild bees are an essential component of agriculture and especially important for crops whose flowers use buzz pollination to spread their pollen. Also known as sonication, buzz pollination is a process in which the pollinators attach to the anther cone of the flower and contract their indirect flight muscles to produce vibrations. Wild buzz pollinators can increase pollen load, which increases the fruit production and quality of the crop.

“Buzz pollinators provide pollination services for select groups of plants, including several vegetable species,” said Greg Wiggins, education and outreach coordinator for NIMBioS. “Our focus on a specific group of pollinators allows us to highlight potential impacts the changes in distributions of these pollinators may have on agricultural production.”

Climate change already affects many species by forcing them to move in order to keep within suitable climatic conditions. In this study, researchers looked at how potential future changes in climate will impact the distribution of buzz pollinators and what effect that will have on the species richness of tomato crops in North America.

“Studying distributional shifts is especially important for species that pollinate the food we eat,” said Luis Carrasco Tornero, lead author and postdoctoral researcher with NIMBioS. “Our study exemplifies the potential impact of climate change on the production of tomato crops due to the distribution changes of pollinator wild bees. Our findings could serve as an example of individual crop impacts due to lack of overlap between crop plants and their pollinator, which might help raise awareness about the direct impacts of climate change to our lives in the next few decades.”

Researchers applied ecological models and scenarios of future climatic conditions to estimate the potential geographic distribution of the buzz pollinators, which are rarely used to investigate possible effects of climate change on plant-animal interactions and food production.

“We show that the magnitude of change projected by different scenarios varies across species, thus this variation needs to be taken into account when working at the community level, with multiple species,” said Mona Papeş, assistant professor in the UT Department of Ecology and Evolutionary Biology. “Our models estimated a decrease in the number of pollinator species in several regions across the US where field tomato crops are grown on a large scale.”

Beyond tomatoes, ecological niche models can be used to assess potential impacts of climate change on other crops that depend on buzz pollinators, such as peppers, eggplants, or potatoes. It also has applications outside agricultural systems.

“Our work further supports the growing body of evidence showing the potential detrimental impacts climate change can have on natural systems,” Wiggins said.

Researchers will continue their work in pollinator distribution and plan focus their next study on what factors contribute to the ability pollinators have to shift their distribution in the face of climate changes.

“We hope our results from the next project can help conservationists find solutions to manage pollinator populations and avoid local extinctions of some pollinator species,” Carrasco said.

The research project was supported by a NIMBioS Summer Research Experiences (SRE) program that provides undergraduate students from across the US the opportunity to spend eight weeks during the summer working in small teams on research that incorporates mathematics to answer questions about biological systems. Undergraduate students from three other universities participated in the research and are co-authors on the paper.

Photo by Robert Kalinagil on Unsplash

Study Finds Protected Areas Vulnerable to Food Security Concerns

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Protected areas are critical to mitigating extinction of species; however, they may also be in conflict with efforts to feed the growing human population.

Paul Armsworth, professor of ecology and researcher with the National Institute for Mathematical and Biological Synthesis (NIMBioS) is the co-author of a new study showing croplands are prevalent in protected areas, which challenges their efficacy meeting conversation goals. Varsha Vijay, a researcher at the University of Maryland’s National Socio-Environmental Synthesis Center (SESYNC) is the lead author.

The study, published in the Proceedings of the National Academy of Sciences, shows that 6% of all global terrestrial protected areas are already made up of cropland, a heavily modified habitat that is often not suitable for supporting wildlife. Worse, 22% of this cropland occurs in areas supposedly enjoying the strictest levels of protection, the keystone of global biodiversity protection efforts.

In order to comprehensively examine global cropland impacts in protected areas for the first time, the authors synthesized a number of remotely sensed cropland estimates and diverse socio-environmental datasets.

Read more about the study at sesync.org.

Faculty Honored for Research, Teaching, and Service

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Each year, Dean Theresa Lee and members of her cabinet, with help from department heads, recognize faculty in the College of Arts and Sciences for their excellence in teaching, research and creative activity, and lifetime achievements. 

Due to the ongoing pandemic, however, we were unable to host the annual awards banquet in-person. Each faculty member received a plaque and congratulations from the dean. We posted a video to the college YouTube channel here, which features each faculty award winner. 

This year, eight faculty in our department received awards for their research, teaching, and service to the university. 

Faculty Academic Outreach Research Awards

The academic outreach awards recognize extraordinary contributions of faculty to the public that occur as an outgrowth of academic pursuits and are related to the university’s academic mission. The Academic Outreach Research Award recognizes faculty whose research and creative activities advance knowledge through the pursuit of their scholarly interests while simultaneously addressing community problems and issues and benefiting the scholar, the discipline, the university, and society. 

Kimberly SheldonThis year, the college awarded an academic outreach research award to Kimberly Sheldon, assistant professor of ecology, who developed a research program that is advancing knowledge while simultaneously addressing a community issue through collaboration with the Eastern Band of Cherokee Indians (EBCI). Sheldon makes use of insects from the Southern Appalachians, including her dung beetle system, and climate change in the region to make her outreach research activities culturally and socially relevant to the EBCI. 

Sheldon received funding from the Cherokee Preservation Foundation and the UT Office of Community Engagement and Outreach to collaborate with the EBCI and the Office of Fish and Wildlife Management to provide summer scientific research opportunities for EBCI high school students. The culturally and socially relevant research experiences that Sheldon has developed and led helps students to see the relevance of STEM literacy in their own lives as well as the number of jobs that require it.

Faculty Academic Outreach Service Awards

The academic outreach awards recognize extraordinary contributions of faculty to the public that occur as an outgrowth of academic pursuits and are related to the university’s academic mission. The Academic Outreach Service Award recognizes faculty who apply their knowledge to the benefit of the community by helping to seek solutions to community problems and issues. Defined more specifically, outreach service extends the faculty’s disciplinary expertise acquired through research, scholarship, and creative activity to the community. 

This year, the college awarded an academic outreach service award to Professor Paul Armsworth, who brings mathematical, statistical, and computational tools to bear to help organizations trying to conserve species, habitats, and ecosystems to make more effective decisions. He works with a range of state and federal agencies, local, national and international nonprofits and for-profit companies with the goal of reducing their environmental impact. 

The same commitment to help seek solutions to community problems and issues is apparent through his service both within academia and to wider society. Beyond contributions made directly through his research, his service contributions to the wider society have included serving on the science advisory council for a major synthesis center whose mission is to see scientific results deployed to improve both nature and human well-being, and serving on major taskforces commissioned by the federal government. These taskforces provided policy guidance on how public lands should be valued in the federal balance sheet and how best to help fish, wildlife, water, land and people adapt to a changing climate.

“When there are so many great examples of outreach and service being undertaken within the College of Arts and Sciences, I feel really honored to have the scholarship that my students, colleagues, and I undertake highlighted in this way,” Armsworth said. “People sometimes talk about outreach and service as something distinct they do alongside their teaching and research. But I’ve always seen the three as a single package. The most interesting opportunities for teaching and research always seem to arise when we roll our sleeves up and look for ways to help people address the pressing, real-world challenges we face in society.”

Faculty Academic Outreach Teaching Awards

The academic outreach awards recognize extraordinary contributions of faculty to the public that occur as an outgrowth of academic pursuits and are related to the university’s academic mission. The Academic Outreach Teaching Award recognizes faculty who extend the university’s instructional capacity to provide learning opportunities to public audiences through workshops, public lectures, and other educational activities. Faculty may also perform outreach teaching by extending their classroom beyond the campus to engage their students in service learning.

This year, the college awarded an academic outreach teaching award to Jessica Budke, assistant professor and director of the University of Tennessee Herbarium. In her role of Herbarium director, Budke is training a new generation of undergraduate and graduate students in the preservation and use of natural history collections, welcoming community volunteers to work in the collection, and driving new approaches to update and make the collection even more useful to the academic and non-academic communities that it serves. She developed an internship program where undergraduate students receive credit in an independent study course for learning and applying curatorial skills that includes collecting, processing, preserving, cataloging, and filing of specimens in the herbarium natural history collection. She also encourages citizen science in the herbarium, welcoming community volunteers to be involved in work ranging from basic specimen processing to digitization and databasing of specimen data.

“I feel especially honored to have received this award from the college,” Budke said. “My teaching outreach has broadly focused on expanding people’s vision of natural history collections. They are often thought of as dusty collections of curiosities, but are actually dynamic resources we are using to answer important questions about conservation, invasive species, climate change, and discovering species new to science. I enjoy sharing hands on experiences with specimens that get people excited about learning more about them and engaging with them through online citizen science activities.”

Outstanding Service Award

Nina FeffermanNina Fefferman, professor of ecology, received the Outstanding Service Award, which recognizes extraordinary service in advancing the mission and goals of the college. 

During the past year, Fefferman took on an impressive level of service related to her expertise in modeling epidemiological events – specifically the COVID-19 pandemic. This work is a logical extension of her earlier work examining Zika and other mosquito-driven disease transmissions, the evolution and spread of antibiotic resistant bacteria, Lyme disease risk, human cooperation in vector control, etc. As a result of her current work, she is also publishing several papers related to pandemic mitigation in a number of types of communities, as well as leveraging insights from prior similar events. 

She served the university by advising the COVID-19 Re-Imagining Fall Task Force and continued to monitor and model the COVID-19 infection data in the fall semester. Fefferman has been interview by six different television outlets, five podcasts, and numerous print media during the past year. She has managed this enormous service while continuing to manage six active grants, undergraduate and graduate students, as well as post-doctoral scholars. 

“I’m very grateful to receive this award,” Fefferman said. “This award reminds me how grateful I am to be in a community that inspires us to care about each other and work, in whatever capacity we each can, for each other’s lives to be better.”

While her level of service has been very high and extremely important in the last year, Fefferman has provided exceptional service to NIMBioS, NSF and NIH, and in a variety of editorial roles over the years, in addition to ongoing public service through public presentations and consultation with various organizations, including ACLU, Vera Institute of Justice, State of Vermont, and ongoing service to the CDC since 2009.

Excellence in Research Award/Creative Achievement Awards

We seek to recognize faculty members who excel in scholarship and creative activity while also being fully engaged in the other responsibilities of faculty jobs, primarily teaching and service. To this end, the college honors faculty in three stages of their research careers – early, mid, and senior – with awards for excellence in research or creative achievement, as well as honoring a faculty with an award for Distinguished Research Career at UT.

Brian O’Meara, professor of ecology, received a mid-career research award. O’Meara is an international leader in the creation, development, and application of phylogenetic methods to answer fundamental questions about the Tree of Life. His work in the areas of parameter inference in phylogenetic models and the study of macroevolutionary processes, particularly the association between diversification rates and continuously distributed trait evolution, is outstanding. He develops cutting edge statistical models, implements them in freely available software, and discusses their interpretation stressing their strengths and limitations in his publications. Further, he applies these methods to important problems in evolutionary biology, resulting in his exceptionally high impact in the field broadly, with contribution in both theory and practice. 

His contributions have pushed the theoretical underpinnings of phylogenetic theory forward in concert with development of methods. Due to the explosion in size of gene sequence-based comparative datasets and the rapid growth in computing power, phylogenetic models have necessarily become more complex. O’Meara is a clear leader among only a handful of scientists worldwide that have been developing and implementing such models. He is the recipient of $2.89M in external support. He has a prolific track record of mentoring in his 12 years at UT. He has mentored 16 postdoctoral fellows and graduated four PhD students who have gone on to successful careers.

“Brian is a generous collaborator with his mentees and members of the EEB community and beyond,” said Susan Kalisz, head of the EEB department. “He is a leader in EEB, serves as associate head, chairs the departmental Diversity and Inclusion Committee, and was recently elected president of the Society of Systematic Biologists.”

Karen W. Hughes, professor of ecology, received the Distinguished Research Career at UT award. Hughes is an internationally recognized scientist. Early in her career, Hughes brought her knowledge of plant tissue culture to the study of fungi, culturing individual fungal spores collected from wild populations across the globe and testing their breeding compatibility. She demonstrated that populations of fungi from different continents – originally considered the same species – represent distinct species unable to interbreed. Her findings transformed how mycologists view fungal species, demonstrating more extensive fungal diversity previously recognized. 

Her early work foreshadowed the revolution in molecular phylogenetics using DNA sequence-level data and she continues to extend these findings. Key to her success is her ability to coordinate multiple collaborators, including students, colleagues, and the public. Recently, Hughes spearheaded an NSF-funded research coordination network of 100 scientists called Deep Hyphae, which led to a major reassessment of the evolutionary history of fungi based on molecular phylogenetic data. Most recently, Hughes secured NSF funding to investigate fungal response to the Gatlinburg wildfires and coordinated and trained forays of professional and amateur (Discover Life in America and GSMNP interns) mycologists to collect post-fire fungi. One early finding reveals that some collections were unique, fire-adapted fungi, which persist within mosses and liverworts for long periods of time, then reproduce and spread when the habitat experiences a fire. Because fungi play critical roles as mutualistic partners in the roots of most plants, as well as in ecosystem functioning, her results have important applications in forestry and basic ecological studies. Hughes has been an exemplar of leadership, research, teaching, and outreach throughout her 47 years at UT.

James R. and Nell W. Cunningham Outstanding Teaching Award 

The James R. and Nell W. Cunningham Outstanding Teaching Award recognizes faculty excellence in teaching. The honor is awarded to a tenured faculty member who demonstrates outstanding classroom teaching. This year, the college recognized Edward Schilling and Urmila Seshagiri for their outstanding teaching. 

Often when we envision a professor who has been teaching for more than 40 years, we think of yellowed note pads or dull lectures. Edward Schilling, professor of ecology, was nominated for this award because as teaching circumstances evolve, so does he, and these changes are solely because of his dedication to student engagement and learning in his courses. His teaching has always been exemplary, but he has shown great adeptness at transitioning to online teaching over the last year that students have truly appreciated. 

As someone who has observed his teaching said, “he takes great pains to make the material he teaches relevant and connected to issues students care about, whether it’s biodiversity, or agriculture, or being able to identify plants in the field. Ed meets the students where they are, and leads them to greater understanding and appreciation for biology.”

In all of his teaching feedback there are consistent themes about his teaching: Professor Schilling is incredibly organized and well prepared and provides students with a hands-on and immersive educational experience because he believes that students who are engaged with the material are more likely to learn the material. 

“It was an incredibly uplifting feeling to learn that I had been selected to receive the Cunningham Teaching Award,” Schilling said. “UT has many outstanding teachers, so to be recognized in this way is truly an honor that I will cherish.”

Faculty Advising Awards

The college recognizes excellence in undergraduate advising, providing rewards for past achievements and encouraging future resourceful and creative efforts in undergraduate advising.

Jennifer Schweitzer, professor of ecology, is recognized for serving as a tireless advocate for undergraduates within her department. Her commitment to student success is demonstrated through her relationships with individual students as well in her associate head role where she ensures that the student experience is the focal point of all conversations regarding curriculum development, teaching rotation, and advising practices. Recently, she developed a resource for the faculty titled “Best Practices in Advising/Mentoring” to assist all faculty in their mentor role with undergraduates. 

Schweitzer also serves as an outstanding mentor to the students in her research lab, where more than 80 percent of the undergraduates who have worked with her have gone on to graduate or professional school.  

“Great mentors bring undergraduates into their lab and involve them in all aspects of being a scientist,” Kalisz said. “A really outstanding mentor like Jen goes above and beyond by mentoring in professional development, choosing a career path, getting into graduate school, navigating work-life balance, and being a woman in science.”  

Kalisz also notes Professor Schweitzer is one of the only faculty members she knows who has a list on their CV of all of the undergraduate students she has advised, including the time span of the relationship and whether or not the student graduated.

“Advising students at UT is such an important part of my job and one that I truly love,” Schweitzer said. “In helping EEB students navigate the biology-EEB curriculum and gain professional development skills I hope we are assisting students in finding and reaching their career goals so they can make a difference in the world. EEB students are so motivated, work so hard, and have such high aspirations for themselves and their futures. It is amazing to see all they achieve. I am very proud to be part of this department and grateful for this kind award.”

Congratulations to all our faculty on your outstanding achievements!

Evolution of Tropical Biodiversity Hotspots

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Chapada do Araripe, Ceará.For decades, scientists have worked to understand the intricacies of biological diversity – from genetic and species diversity to ecological diversity.

As scientists began to understand the depths of diversity across the planet, they noticed an interesting pattern. The number of species increases drastically from the Poles to the Equator. This phenomenon, known as the latitudinal gradient of species diversity, has helped define the tropics as home to most of the world’s biodiversity. From plants and insects to birds, amphibians, and mammals, scientists estimate that tropical forests contain more than half the species on Earth.

These biologically rich areas are known as biodiversity hotspots. To qualify as a hotspot, a region must have at least 1,500 vascular plants species occurring nowhere else and have 30 percent or less of its original natural vegetation. In other words, biodiversity hotspots must be irreplaceable, but also threatened.

While scientists agree that most biological diversity originated in the tropics, the jury is still out on how tropical species diversity formed and how it is maintained. A new study published in Science addresses these long-standing questions.

In “The evolution of tropical biodiversity hotspots,” researchers argue that tropical species form faster in harsh, species-poor areas, but accumulate in climatically moderate areas to form hotspots of species diversity. Drawing on decades of expeditions and research in the tropics and the scientists’ own knowledge and sampling of tropical bird diversity, they assembled a large and complete phylogenomic dataset for a detailed investigation of tropical diversification.

Liz Derryberry“This is our magnum opus,” said Elizabeth Derryberry, associate professor in the UT Department of Ecology and Evolutionary Biology (EEB) and a senior author of the study. “This research is the product of a decades-long international collaboration to produce a completely sampled evolutionary history of a massive tropical radiation – the 1,306 species of suboscine passerine birds.”

Roughly one in three Neotropical bird species is a suboscine, making it the predominant avian group in Neotropic terrestrial habitats – from the Andes snow line to the Amazon lowlands – and the perfect group to examine the origins of tropical biodiversity.

Michael Harvey“The tropics are a natural laboratory for speciation research,” said Michael Harvey, recent EEB postdoc and lead author of the study. “Many high-profile studies over the years sought answers to fundamental questions concerning species formation and maintenance, but even the best of these studies sampled only a minority of the existing species within the clade in question.”

In addition, nearly all of the previous studies used highly incomplete data matrices and supertree analyses, which left results open to large estimation errors in downstream analysis, according to Derryberry.

Brian O'MearaFor this study, Derryberry, Harvey, EEB Professor Brian O’Meara, and fellow researchers used a time-calibrated phylogenomic tree to provide information needed for estimating the dynamics of suboscine diversification across time, lineages, and geography. They also used the tree to test links between the dynamics and potential drivers of tropical diversity.

“We took no shortcuts in this study,” Derryberry said. “We leveraged this unparalleled sampling of tropical diversity to illustrate the tempo and geography of evolution in the tropics. It is the first study to demonstrate conclusively that tropical biodiversity hotspots are linked to climates that are both moderate and stable.”

The team discovered species-rich regions in the tropics contain diversity accumulated during a protracted evolutionary period and are not just a locus of young diversity. A key result of their study is that the best predictor of elevated speciation rates in New World suboscines is low species diversity. In other words, new species form at higher rates in areas containing relatively few species.

“The qualities that nurture diversity, lower extinction, and promote the gradual accumulation of species are, paradoxically, not the ones that support biodiversity hotspots,” Harvey said. “The hotspots are seeded by species born outside the hotspot in areas characterized by more extreme and less climatically stable climates.”

The team discovered that, overall, extreme environments limit species diversity, but increase opportunities for populations to evolve to become distinct species. Moderate climates, on the other hand, limit speciation, but provide more opportunities for species diversity to accumulate.

“Our study is the first to be able to address tropical diversification with a large, comprehensively sampled clade and will pave the way for future investigations of evolution in the world’s diversity hotspots,” Derryberry said.

The international collaboration for this study included researchers from Colombia, Brazil, Uruguay, and Venezuela, as well as ornithologists from groups underrepresented in the sciences, include Latinx and women researchers.

Parque Intervales, Riveirão Grande, SP Outubro - 2011“This paper marks not only a change in our understanding of evolution in the tropics, but also in acknowledgement and valuation of the diversity of culture, expertise, and perspective in the field of ornithology,” Derryberry said.

The US National Science Foundation, Brazilian Council for Scientific and Technological Development, and the São Paulo Research Foundation funded the study.

The Queen of Spiders Has Retired

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susan riechertShe has been one of the leading scientists in the field of animal behavior for decades, and a role model for generations of young researchers. Her work with K-12 schools in Tennessee has touched thousands of students over the last 20 years, instilling a passion for biology and for the scientific process. And, as she says, in the 1970s, she helped stopped a war from occurring between two Central American countries.

Susan Riechert, University of Tennessee Distinguished Service Professor in the Department of Ecology and Evolutionary Biology and UT Chancellors Professor, has retired. Because the pandemic and shut-downs threw everything into flux this spring and summer, her retirement did not get the publicity it deserved. Riechert’s impact on the field of animal behavior and on generations of UT students is immense, and her formal departure from the university will long be felt.

Like many animal biologists, Riechert’s professional career built off of an early love of animals. As she described in a Science Forum presentation at UT February 21, 2020, as a young student she worked with a range of species from spider monkeys to freshwater fish. While serving as a teaching assistant for a fish ecology course at the University of Wisconsin, she started collecting local spiders and soon realized she was quite good at identifying them (not an easy task). Her career as a spider biologist began.

At the time when Riechert was carrying out her foundational research projects, it was relatively rare for a woman to be conducting fieldwork in isolated areas. One of her first major independent field studies took place on the Carrizozo lava beds of New Mexico, where she spent seven months a year for two years camped out by herself in primitive conditions. She was trying to understand how spider populations could persist in the extremely harsh and dry habitats of the lava beds and grasslands where she was working.

Testing some key predictions of physics models of heat transfer, Riechert discovered that physical properties of the environment only partially accounted for the locations spiders chose for their web-sites. Individuals competed for the best sites and defended space around the webs they placed in these locations. This led her to develop and then test some of the early mathematical models of game theory with the spiders she was studying. These initial studies were to go on to influence dozens of young researchers who are now major figures in the fields of behavioral ecology and behavioral evolution.

Professor Alison Bell of the University of Illinois is one of those major figures.

“Professor Riechert’s early work was very influential in how I wanted to approach and how I thought about understanding behavioral evolution.,” Bell said.

Riechert’s career paralleled that of another major figure (and fellow spider biologist) in the field, Professor George Uetz of the University of Cincinnati. Uetz recalled reading Riechert’s earliest published study on what became one of her most-studied species and thinking it was a “stellar piece of work.” Around this point of time in the mid-1970s, territoriality in species was thought to be restricted to mammals and birds.

“Riechert’s work on the desert grass spider was totally anti-dogmatic – the idea that an invertebrate like a spider could be territorial and could have behavioral strategies that fit ecological circumstances,” Uetz said. “It was ground-breaking work,” he said, and it led her to generate new research projects with her spiders that “contributed to a lot of major paradigms in the field of animal behavior.”

Some researchers of animal behavior focus on a particular topic of study, and use a variety of species – sometimes very different species – to test hypotheses on that topic. Other researchers take a different route, and learn as much as they possibly can about a single species such that it becomes a “model” species that can be used to test a wide variety of questions in a range of different disciplines. Riechert took the latter route. As she noted about her model species in her Science Forum talk, “I just let it take me wherever it went, and I wasn’t wedded to one particular type of project.”

Since her foundational studies, her more recent work on grass spiders has included the physiological underpinnings of behavior, behavioral genetics, sexual selection theory, predator-prey dynamics, pest species control, and animal personality.

A University of Tennessee colleague, Professor Gordon Burghardt, noted that some of her biggest impacts on the field were her studies “on the ecological and genetic differences between spider populations and their influence on social aggression and competition.” From her earliest studies, Riechert had a sense for what would be the next big ideas in the field of animal behavior and then applying or testing them with her grass spiders – and it could be argued that Riechert’s work was instrumental in raising the importance of these new perspectives and methods in the field. It should also be noted that, in addition to her work on grass spiders, she was a pioneer in the study of social spiders. These animals, often in tropical countries, rather than being solitary and territorial, live in large groups in complex webs containing up to hundreds of spiders.

During her career, Riechert has published more 100 articles, chapters, and commentaries. Her work has been cited in other published studies more than 8,000 times. Importantly, her work has continuing influence, as more than 2,000 of those citations occurred in just the past five years.

Riechert has not devoted all of her academic time to grass spiders. A major initiative she undertook in the late 1990s, and that continues today, was her “Biology in a Box” program. This program brings innovative and exciting hands-on science into K-12 classrooms throughout the state of Tennessee. The different modules in the program, which come in actual wooden boxes, each foster critical thinking and a deeper understanding of science as a verb – a process of inquiry and testing of ideas.

Riechert built this program from the ground up. It has now reached roughly 75% of the counties and more than 300,000 students in the state, and has begun to engage students in other states as well due to the project’s web components. Professor Susan Kalisz, head of the Department of Ecology and Evolutionary Biology at UT, noted that Riechert is “really passionate about that . . . the amount of effort and the creativity that she brings to all the projects she is involved with is just fabulous.”

This passion for science extends to her own teaching. She and her family have long had a menagerie of different non-human animal companions, including a large and quite heavy tortoise. Kalisz remarked that Riechert had a special trailer built so that she could drive the tortoise into campus on occasion to get her students more direct experience with this interesting and, for eastern TN, uncommon animal. “She empowers people to love biology.”

About that averted war? Riechert described the story of a spider collecting trip through Central America in her Science Forum talk. Camping out one night in El Salvador, security forces picked her group up and brought everyone to the area colonel’s compound, purportedly for their own safety. As soldiers drank into the late hours, they divulged an attack they planned against Honduran forces at the nearby border. The next morning, as Riechert and colleagues crossed that border, they informed the US peacekeeping forces there of those overheard plans to attack. US personnel helped keep the peace there and Riechert “helped prevent a war.”

Riechert’s influence touched every part of an academic’s life. UT Professor Arthur Echternacht, who joined the same department as Riechert at roughly the same time, noted over email that she was the exemplary academic citizen in that “she more than carried her weight with respect to service to the department and elsewhere in the university, and in her interactions with the community at large, [and] I’ve tried to meet her standards.”

Uetz commented on the last time he saw Riechert, at a meeting of the Animal Behavior Society in Milwaukee. He was walking to lunch with his own graduate student and ran into Riechert. They all had lunch together and when Uetz’s graduate student realized how well he and Riechert knew one another, “my status grew in the eyes of my own student.” With regard to the study of spiders, “she is the Queen . . . Everyone looks up to her.”

-By Todd Freeberg