Spring 2023 EEB honors graduate Colton Adams received a Fulbright student award. Read about his plans here: https://news.utk.edu/2023/05/17/11-ut-students-receive-fulbright-awards/?utm_source=newsletter&utm_medium=email&utm_content=2023-24%20Fulbright%20student%20awards&utm_campaign=TN%20Today
Jonathan Dickey, a graduate student in the Fordyce lab, investigates the mediation of pollinator network assembly by rhizospheric soil microbiota through reproductive plant traits and aboveground fitness consequences in the genus Salvia. He demonstrates this by sampling soil microbiomes of Salvia lyrata at various phenological stages of development while measuring traits like photosynthetic biomass and floral abundance.
“We have seen before that the main driver of pollinator visitation and community composition relative to ecoregion and soil context is driven by plant composition, floral traits, and rewards, but how do belowground communities influence plant distribution and relative attractiveness towards insects?” Jonathan says.
Jonathan plans to quantify soil microbial communities based on 16S rRNA gene abundance using Illumina next-generation sequencing for each plant replicate per phenological stage. Jonathan’s exploration of community assembly with Salvia lyrata is multidisciplinary and connects community ecology with population level, evolutionary processes like the phenotypic selection. Furthermore, he has been optimizing a protocol for seed sterilization and germination for the genus Salvia by repeated processes that include seed coat surface sterilization and heat treatments to remove all potential endophytic microbiota. Upon successful germination, Jonathan plans to use soil microbial slurries associated with juveniles and flowering individuals to measure flowering time, abundance, corolla tube length, and ultimately pollinator visitation rates.
Additionally, he uses species distribution modeling (SDMs) to inspect how nutrient based mutualisms can breakdown in future climate scenarios. Through this exploration, he explicitly states the spatial extent at which potential niche divergence could occur in Eastern North America and the implications for conservation and effects on higher trophic levels. From yet another avenue, Jonathan is writing an R package employing MuSSE, a phylogenetic method, to analyze population size as a trait dependent on the presence of a stress-tolerant gene. The utility of this package is versatile and can provide a nuanced look at community disassembly in light of climate change or various disturbance events.
“We’re just now beginning to fully appreciate the vital role that microbial communities play across levels of ecological organization,” Fordyce says. “Jonathan’s project, entirely of his own design, is timely and novel. I’m looking forward to seeing what he discovers.”
Although it is likely most people have experienced ants at a picnic, they may not realize ants are important seed dispersers, a mutualism referred to by ecologists as myrmecochory. Seed dispersal by ants exists worldwide, but the eastern deciduous forests are a hotspot for this ant-plant interaction. Approximately 35 percent of the herbaceous plants in the understory of forests in eastern North America rely on ants for seed dispersal. Plant species that have coevolved myrmecochory have an oil-rich appendage, known as an elaiosome. The elaiosome attracts the ants with chemical cues. Ants pick up the seed by the elaiosome and return with it to their nest where they feed the elaiosome to their brood. The seed either remains in the nest or is taken outside of the nest. Thus, in myrmecochory, ants gain food, and seeds receive dispersal away from their parent plant, protection from seed predators, and a nutrient-rich germination site in or around ant nests.
Additional organisms likely play a role in this interaction. Microbes, such as bacteria and fungi, are abundant in soil and decaying wood environments where ants nest and seeds germinate. Some of these microbes are harmful to plants or ants, so ants and plants have defenses against these pathogens. Each partner in the ant seed dispersal mutualism has the potential to affect the other partner’s microbes. Chloe Lash, a graduate student in the Kwit Lab, is investigating the effects of chemicals and microbes in this mutualism for her dissertation.
Chloe uses advanced chemical identification techniques to investigate plant and ant chemicals and their potential antimicrobial properties. A combination of traditional and next generation sequencing techniques allows Chloe to understand the microbial loads that both ants and seeds encounter and how those microbial communities change when the partners interact with each other. This novel incorporation of chemical and microbial facets into myrmecochory will contribute to understanding the evolution and persistence of the myrmecochory mutualisms and can help scientists predict the consequences of global change-related disruptions.
The Ecology and Evolutionary Biology Department had their annual awards ceremony on Friday, May 11, 2018. Congratulations to:
o 2018 EEB Outstanding Master’s Thesis: Chad Stachowiak
o 2018 EEB Jim Tanner Outstanding Dissertation: Sara Lipshutz
o 2018 EEB Best Progress Toward Dissertation: Chloe Lash
o 2018 EEB Sandy Echternacht Outstanding Teaching by a Graduate Student: Melqui Gamba-Rios
o 2018 EEB Outstanding Publication by a Graduate Student: Jennifer Summers
o 2018 EEB Outstanding Outreach and Community Service by a Graduate Student: Maggie Mamantov
o 2018 EEB Tom Hallam Appreciation Award: Angela Chuang
o 2018 Outstanding Undergraduate Poster Award: Daniel Malagon (Kalisz Lab) and honorable mentions Samantha Cahill (Giam Lab) and Alexis Case (Hughes Lab)
o 2018 EEB Outstanding Undergraduate: Alexis Case
o 2018 EEB Outstanding Undergraduate Research: Anna Cameron
o 2018 EEB Undergraduate Award for Professional Promise: Kane Lawhorn
o 2018 EEB Outstanding Outreach and Community Service by an Undergraduate Student: Justin Baldwin
o 2018 EEB Outstanding Administrative Service Award: Jeff Martin
Congratulations to Jayne Lampley (Schilling Lab), who has received a Hollaender Fellowship from the Division of Biology! This Fellowship recognizes an outstanding graduate student within the division, that shows outstanding academic qualifications, research accomplishments, and scientific/professional promise.
EEB undergraduate Justin Baldwin and EEB graduate student Maggie Mamantov (Sheldon Lab) both received honorable mentions in the prestigious National Science Foundation Graduate Research Fellowship Program. This program selects early career students with high potential in science.
Amanda Wilson Carter (postdoc, Sheldon Lab) was awarded an NSF Postdoctoral Research Fellowship in Biology! Using dung beetles, she will integrate thermal plasticity across life stages with maternal behavior to understand the mechanisms driving responses to increased temperature variation.
Congratulations to EEB graduate student Miranda Chen. Miranda was selected as a recipient of the 2018–2019 Shipley-Swann Graduate Fellowship. By receiving this fellowship, Miranda is being recognized as one of the most promising graduate and professional students at the University of Tennessee, Knoxville.
The Graduate Student Senate Awards were held on April 4. Check out all the winners from EEB!
Graduate Research Mentor of the Year: Associate Professor Elisabeth Schussler
Excellence in Teaching: Justin Hendy (Small Lab)
Excellence in Research: Sara Lipshutz (Derryberry Lab)
Excellence in Service: Alannie Grant (Kalisz Lab)
Graduate Student Chad Stachowiak (Armsworth Lab), is a finalist for a 2018 Presidential Management Fellowship.
“The PMF Program is a flagship leadership development program at the entry level for advanced degree candidates. It was created more than three decades ago by Executive Order and has gone through many changes over the years. The Program attracts and selects the best candidates possible, but is really designed with a more narrow focus – developing a cadre of potential government leaders. It provides some sustenance during the first years of employment and encourages development of leadership capabilities. The PMF Program inculcates a lasting bond as well as a spirit of public service, ultimately encouraging and leading to a career in the government.”
Approximately 6,040 applications were received and 425 applicants were selected as Finalists. The 2018 Finalists’ pool represents approximately 69 different disciplines, 161 academic institutions, and 15% are veterans.