October Grad Spotlight: Jenn Houtz


I am a first-year PhD student in the Vitousek Lab. My research interests include neuroendocrinology, behavioral ecology, and microbial ecology. During my doctoral research, I intend to characterize the impacts of gut microbiome composition on host phenotypic traits vital to stress responsiveness and their fitness consequences. More specifically, I’m interested in the mechanistic links between the gut microbiome and stress-related changes in physiology, behavior, and brain development in tree swallows.


Outside research, I am passionate about public outreach and citizen science efforts. I love to encourage younger generations to confidently pursue a career in STEM by sharing my own experiences with them. I also love hiking, kayaking, and dancing (ballet, jazz, and tap) in my spare time!


Summer defenses

Several graduate students in our department defended their dissertations this past summer! Our dissertation defenses include an oral exam with faculty (the “B Exam”) and a public presentation to the department. Read on to find out about three recent Cornell PhDs, in their own words!

Ezra Lencer

My thesis investigated the developmental and genetic changes underlying the evolution of different ecologically important craniofacial phenotypes in a geologically young radiation of pupfishes (genus Cyprinodon) endemic to San Salvador Island, Bahamas. Combining classic morphology with emerging technologies in genomics and cell biology, I was able to show how changes to gene expression produce novel craniofacial phenotypes by affecting jaw growth rates via modifications to cell proliferation dynamics in the heads of each species during development.

I am currently an NIH postdoctoral fellow at CU Anschutz Medical Campus, where I am working on neural crest cell migration with Kristin Artinger and Rytis Prekeris.


Renee Petipas

Plant-associated microbes affect a wide-variety of plant functional traits, and thus they likely affect patterns of plant local adaptation. However, the role of microbes in plant local adaptation is rarely tested. For my dissertation, I explored this idea using reciprocal transplant experiments, moving seeds and soils between limestone barrens and old-fields in northern New York. I found that microbes change patterns of plant local adaptation and are particularly important for plants growing in the harsh limestone barren environment. Upon completion of my PhD, I received an NSF-postdoctoral research fellowship in biology (PRFB) and am currently working at Washington State University exploring coevolution between Medicago lupulina and Ensifer meliloti using museum specimens.


Katie Sirianni

Broadly, I study what determines the distribution of zooplankton populations throughout a landscape with many small rock pools. Dispersal is important because small rock pools are inconsistent habitat– they can dry out, get too hot, or too salty. In addition to dispersing among pools, these zooplankton can disperse in time by making eggs that hatch a long time (years!) after they are produced. These eggs can survive many conditions that the active zooplankton wouldn’t be able to tolerate. I measured how two similar zooplankton species use the combination of dispersal in time and space to persist in these harsh habitat conditions.

Currently, I am teaching classes on Ecology and Field Ecology at Cornell.


September: Colleen Miller


I am a first-year graduate student interested in studying anthropogenic stressors on Tree Swallow populations in the Vitousek Lab. With a background in population level ecology, I have become increasingly interested in understanding underlying factors to large scale patterns. By studying across organizational levels, I intend to develop a deeper understanding of how stressors such as light or noise pollution vary within and across populations. I hope to better describe how urbanized landscapes may impact natural communities in a rapidly developing world.

Alongside my research, I work to create a supportive atmosphere for others enduring stress, work-life balance or mental wellness issues. Supportive scientific communities are the strongest. Outside of my work, you can find me pursuing one of one hundred hobbies! I enjoy cooking, reading, playing music and hiking to name a few—focusing on one hobby was never my path.


Welcome Picnic

To kick off the school year, grad students hosted our annual EEB Department Picnic on August 23. The Picnic committee grilled meats and veggies on the shore of Cayuga lake, while department members arrived with homemade sides and desserts. This year, we also provided a brief orientation for incoming first-years on the ins and outs of the department. Welcome to all the new graduate students, and happy start of the semester!

August: Lizzie Lombardi

I am a fourth-year graduate student studying plant-virus interactions in the Power lab. My work considers the impact of environmental change on plant response to viral associations. In order to integrate host adaptation to both variable abiotic conditions and heterogeneous biotic pressures (i.e. the real world), I study a single plant across its’ full known range in the mountains of western North America. I am currently assaying plant populations for viruses in order to build a viral diversity baseline across alpine and montane ecosystems, which may inform predictions regarding future viral range shifts into naïve host populations. In addition, I am also conducting common garden experiments to assess the roles that host genotype and environment play in facilitating the spread of viruses to new plants and environments.

I study alpine ecology because I care about mountains, and you’ll often find me in them even when I’m not working. I am also a fan of science fiction and evolutionary agriculture, and the combination thereof.


July: Keeley MacNeil

I’m a finishing PhD Candidate in Alex Flecker’s lab. I am interested in drivers of elemental movement through streams, how their cycles interact and how elements are taken up and used by aquatic organisms. I study streams in Ecuador that are contaminated with arsenic as a result of geothermal activity and how nutrient availability in those streams affects how much arsenic is retained in the food web or transported further downstream.  Understanding how arsenic interacts with more common elements (carbon, nitrogen and phosphorus) is important given the prevalence of arsenic (more than 10% of US streams are above the drinking water limit!), and the influence of humans on stream nutrient chemistry from agricultural runoff.

In addition to biogeochemical cycling, I am also passionate about sustainability and co-chair the Atkinson Center for a Sustainable Future Fellows groups, which promotes various events surrounding sustainability. When not in the field, lab, or office, you might find me on the rock wall or hiking with my wild jungle dog, who adopted me at a field station in Trinidad.


June: Emily Funk

I am a fifth year student in Amy McCune’s lab. I study the evolution of novel phenotypes using comparative developmental genetics. More specifically, I am investigating the evolution of the gas bladder in ray-finned fishes from the lungs of the bony-vertebrate common ancestor. The key morphological difference between these homologous organs is the site of budding from the foregut; the gas bladder buds dorsally and the lungs bud ventrally. Using immunohistochemistry and tissue-specific transcriptomics, I am comparing the gene expression patterns during gas bladder development in bowfin and lung development in bichirs looking for dorsoventral patterning similarities and differences.

When I’m not hanging out with the fishes, I enjoy trail running, biking, and hiking/backpacking through the mountains.

May: Katie Rondem

I’m a second-year grad student in the Reed Lab and am broadly interested in Evo-Devo–more specifically, how gene regulation contributes to the evolution of animal diversity.

Genomic comparisons between diverse animals reveal remarkable conservation between gene coding sequences, suggesting very different body forms are built using very similar sets of genes. How, then, has animal diversity evolved? One answer may lie in the genomic regions that regulate these genes, or regulatory regions. Regulatory regions tell genes when, where and how long they should be expressed, and they may hold the key to how all of this amazing animal diversity has developed and evolved. To give proof to this theory, I’m currently trying to show that the regulatory regions of a known butterfly color patterning gene are responsible for variation in wing color pattern in Heliconius butterflies using CRISPR gene editing techniques.

When I’m not doing research, I’m probably either playing Catan, binge-reading a fantasy series, or planning my next trip out west to go camping, hiking or skiing.


April: Jonathan Hughes

I’m a 2nd year PhD Student in Jeremy Searle’s lab. My research interests lie primarily in the realms of population genetics, speciation, and phylogenetics, especially as they apply to mammals. I’ve previously worked with cows, mammoths, and giant sloths, and I’m currently using house mice to answer questions of chromosome evolution and hybridisation. House mice of the subspecies Mus musculus domesticus occasionally experience chromosome fusions, and mice with different chromosomal rearrangements are able to interbreed with seemingly no detriment, which is unusual. I’m interested in exploring the mechanisms that generate and govern these rearrangements, what they mean for the genetic diversity of house mice, and the degree to which chromosomal variation is driving speciation in these mice.

When not basking in the warm glow of a computer monitor, I can usually be found on a hiking trail, in a mosh pit, or down the pub. I’m always searching for more people to play board games and be opinionated about movies with.

Diversity Preview Weekend

From March 8-11, grad students in our department led the collaborative outreach event that is Diversity Preview Weekend! For the second year, we organized faculty and postdoc interviews, workshops, and tours to introduce talented underrepresented minority students and researchers to Cornell and the graduate school application process. Three departments hosted attendees: EEB, the School of Integrated Plant Sciences (SIPS), and Entomology. In the coming weeks, attendees will be matched to graduate student mentors in each department to guide them through the nitty gritty of writing emails to potential advisors, tailoring their personal statements to positions, and applying for fellowships. Our gratitude comes in threes: Thanks to all the attendees for coming – it was so exciting to meet you! Thanks to the tireless organizers who coordinated a packed weekend of events across three (!) different departments. And thanks to all faculty, postdocs, and grads who hosted attendees, interviewed them, and helped them expand their academic networks. Thank you!


Stepfanie Aguillon (EEB)
Amelia Weiss (EEB)
Kass Urban-Mead (Entomology)
John McMullen (Entomology)
Michelle Laterrade (SIPS)
Julia Miller (SIPS)
Chris Peritore (SIPS)
Nick Segerson (SIPS)