Emily Le Sage, PhD

Integrative biologist in translational ecology

Dedicated to promoting diversity of both identities in STEM and life on our planet!

Find me on the oSTEM Mentoring Program

Science is for everybody
Las ciencias son para todas

News feed

September 22, 2021

BII funded to study ecological resilience

Our Biological Integration Institute proposal was funded by NSF! Meet RIBBiTR, the Resilience Institute Bridging Biological Training and Research. Congratulations team, I am thrilled to continue our integrative work to gain a deep understanding of how biological systems achieve resilience to emerging infectious diseases and other global change stressors. Read the press article here.

June 15, 2021

New Postdoc position!

I joined the lab of Brent Sewall at Temple University to work on some intriguing bat population and disease data. Looking forward to sharing what we find with you all!

Feb 2, 2021

Ecological adaptations explain phenotypic variation in wood frogs: "country" frogs aren't adapted to living in dense "city" conditions

In our recent study published in Heredity, the latitudinal cline in body size found in wood frogs appears to be driven by isolation by ecology rather than geographic distance. Our results suggest that both climate and conspecific competition (competition with individuals of the same species) selection pressures drive population divergence in developmental traits in this species.


Range-wide studies like this one are essential for accurate predictions of population’s responses to ongoing ecological change.

Read the full paper here

or email me for the PDF!

Nov 12, 2020

Winter is coming: Do frogs prepare their constitutive defenses for the cold?

Like many animals, frogs have seasonal infectious disease patterns. We wondered if their pathogen defenses also displayed seasonal rhythms, and were surprised to find that their stored peptide defenses closely followed the pattern of infection peaks in time. This synchrony between host and pathogen could be a result of similar underlying environmental forces, such as temperature, or a evolutionary arms race in which frogs prepare for the worst.

Our latest study tracks leopard frog peptide and microbiome defenses through seasonal changes in Batrachochytrium dendrobatidis (Bd) infection prevalence and microclimate.

Read more here

(or email for the PDF! First paper with my new name!)

May 6, 2020

Stress increases the severity of epidemics

In the time of a global pandemic, understanding how stressors lead to more susceptible and infectious hosts is increasingly relevant. Human and animals alike, chronic stressors are known to suppress immunity. But how do they affect epidemics? Predicting these sporadic and non-linear events requires a deeper understanding of how poor conditions affect interacting epidemiological factors to cause more severe and more frequent epidemics.

Read more

Apr 23, 2019

Battle of host and pathogen

Another great study out by the Rollins-Smith lab identifying more ways the pathogenic fungus Bd (Batrachochytrium dendrobatidis) can knock down a frog's immune defenses. Discoveries like these can be a foundation for research that helps humans and frogs combat diseases and cancer.

Read more

October 22, 2018

Seasons may change, and so do disease dynamics

Using the exciting new method of environmental DNA sampling, we were able to take the first glimpse at how a community of amphibians experiences a ranavirus outbreak. Identifying how the epidemic curve relates to eDNA levels in pond water can help field biologists determine if a population is at risk--just by taking a water sample. Here we determined that mortality occurred during sensitive developmental windows once pond temperatures were warm.

Find the paper here

Oct 4, 2018

Departmental Seminar

My post-doc fellowship has focused on climate change effects on host-pathogen interactions. I present an update of our long-term data which captures variation across seasons and host immunity that coincide with infection dynamics. Giving the biomedical audience a refresher on ecological and evolutionary drivers of disease and making connections to human health was the focus of my talk.

August 4, 2018

A blue frog in TN?

Ever wonder what makes a frog green? While sampling for amphibian diseases on the Air Force Base near Tullahoma, TN, we encountered a sight rarely seen. A leopard frog, which is usually green, with mottled blue skin!

Check out this neat find!

Axanthic means "without yellow". When blue and yellow pigment layers combine we see green skin, and when yellow is missing, the blue shines through.

October 28, 2017

First MegaMicrobe a success!

More than 200 people of all ages came to the free outreach event put on by VUMC researchers. The Rollins-Smith lab showcased the local amphibian species and increased awareness of these sensitive creatures and the diseases that inflict them. Join us again next year!