Faculty Research Interests

Michael Caldwell: I study the ways in which animals use vibrations traveling through surfaces, such as the ground or plant stems, to assess their world. Although we know far less about how animals use vibrations, as opposed to other sensory modalities like vision or hearing, we do know that vibrational information is important in the communication, foraging, and risk assessment behavior of hundreds of thousands of species.

Methods in my lab include the recording and playback of vibrational and sound signals produced by animals, video analysis of behavioral responses to these signals, and the measurement of vibrations as they propagate through body tissues and the environment. I do not require any previous experience of students wishing to conduct 460 projects in my lab, but do expect a willingness to learn new techniques, including software tools, and a careful attention to detail. While most of my work focuses on vibrational communication in treefrogs, I would be excited to see student projects with a broader range of organisms in my lab.

Véronique Delesalle: Preferred experience- having taken Bio 204 – Phage Genomics Have you ever wondered about the factors that allow a pathogen to jump from one host to another? What makes a pathogen capable of invading lots of hosts or just a few hosts? These are ecological and evolutionary questions and my lab is answering these questions, using bacteriophages, viruses that “eat” bacteria, as the model pathogen. In particular, we want to understand:

  • what factors determine a phage’s host range (their ability to infect a few versus many bacterial strains, to be specialists versus generalists);
  • how phages evolve as they encounter different bacterial strains to infect;
  • the relative importance of mutation versus recombination (horizontal gene transfer) in the process of adaptation in phages; and
  • the spatial and temporal scales at which these interactions take place (g., how does the diversity of phages and hosts change along these two dimensions).

We are working with two different bacteriophage systems:

1) the phages of Bacillus subtilis. This soil bacterium is one of the best-studied bacterial species and working with this species comes with all the benefits associated with model organisms. We are describing the diversity of phages that can lyse this bacterium, exploring the genetic factors that determine the host range of our phages and conducting experimental evolution studies.
2) the phages of plant pathogens.
This work is done in collaboration with Dr. Koskella (UC Berkeley) with our contribution being the genomics/bioinformatic analyses

Recent publications with student co-authors*:

Delesalle V.A., B.E. Tomko*, Albert C. Vill*, Katherine Boas*, and Greg P. Krukonis. 2022. Forty years without family: Three novel bacteriophages with high similarity to SPP1 reveal decades of evolutionary stasis since the isolation of their famous relative. Viruses 2022 Sep 23;14(10):2106. 

Vill*, A.C., V.A. Delesalle, B.E. Tomko*, K.B. Lichty*, M.S. Strine*, A.A. Guffey*, E.A. 

Burton*, N.T. Tanke* and G.P. Krukonis. 2022. Comparative genomics of six lytic Bacillus subtilis phages from the Southwest United States. PHAGE Sep 2022.171-178


Peter Fong: I work on the aquatic toxicology of human pharmaceuticals released from wastewater treatment plants, engineered nanoparticles, the behavior of aquatic organisms, and the physiological mechanisms of pharmaceutical action. I am also interested in mechanisms by which reproductive processes are controlled. I welcome into my lab, energetic students interested in researching any of these topics. I teach Introductory Biology for majors (Biology 111 and 112), Freshwater Biology (Biology 307), and Invertebrate Zoology (Biology 227).

Recent senior thesis students:

Isabelle Hanna (Spring, 2020). The effect of the antidepressant fluoxetine on bleaching (loss of symbionts) in the sea anemone Aiptasia pallida.

Kathleen Paul (Fall, 2017). The effect of antifoulant medetomidine and SSRI sertraline on development, behavior, and pigmentation in African clawed frog tadpoles (Xenopus laevis).

Amelia Graham and Marisa Hadley (ES 400 Senior Theses, Spring, 2016). A comparison of the effects of imidacloprid and methoxychlor on Rusty Crayfish (Orconectes rusticus) righting response.

Recent publications with student co-authors*:

Fong, P.P., Kelsey E. DiPenta*, Sarahrose M. Jonik*, and Courtney D. Ward*. 2019. Short-term exposure to tricyclic antidepressants delays righting time in marine and freshwater snails with evidence for low-dose stimulation of righting speed by imipramine. Environmental Science and Pollution Research 26(8): 7840-7846.

Fong, P.P., *Lambert, O.J., *Hoagland, M.L., and *Kurtz, E.R. 2018. Differential sensitivity to the antifouling chemical medetomidine between wood frog and American toad tadpoles with evidence for low-dose stimulation and high-dose inhibition of metamorphosis. Environmental Science and Pollution Research 25(20): 19470-19479.

*Barr, J.M., *Palmucci, J.R., *Lambert, O.J., and Fong, P.P. 2018. Exposure to the antifouling chemical medetomidine slows development, reduces body mass and delays metamorphosis in wood frog (Lithobates sylvaticus) tadpoles. Environmental Science and Pollution Research 25(11): 10630-10635.

Thompson, L.B. Carfagno, G.L.F., Andresen, K., *Sitton, A.J., *Bury, T.B., *Lee, L.L., *Lerner, K.T., and Fong, P.P. 2017. Differential uptake of gold nanoparticles by two species of tadpole, the wood frog (Lithobates sylvaticus) and the bullfrog (L. catesbeianus). Environmental Toxicology & Chemistry 36(12): 3351-3358.


Kazuo Hiraizumi: The Hiraizumi Lab is interested in genetic basis for enzyme activity variation using a class of digestive enzymes called dipeptidases in Drosophila melanogaster as a model system. Dipeptidases belong to a class of digestive enzymes and are found ubiquitously among organisms in every kingdom. These enzymes hydrolyze peptide bonds to provide amino acids for various metabolic and physiological processes. The level of catalytic activity of dipeptidases is a quantitative phenotype that varies between individuals in a continuous distribution within a natural population for any species. The genetic, molecular, and biochemical basis for such variation could be differences in the number of enzyme molecules that are produced (related to transcriptional or translational efficiency) or in the structure of the enzyme molecule (related to amino acid composition or sequence). Identification and understanding of genetic factors that affect regulation of these enzyme-coding genes has relevant medical applications, given that reduction in enzyme levels of certain dipeptidases in humans is associated with disorders such as Huntington Disease, Alzheimer Disease, Crohn’s Disease, and Celiac Disease. Student projects involve a number of different techniques and approaches in molecular and cell biology, genetics, and biostatistics. 

Justin Winkel (2022). "Construction of sgRNA Expression Vectors for CRISPR/Cas9 in Drosophila melanogaster"

Nate Rell (2022). "Characterization of Dipeptidase-C mRNA Isoforms in Drosophila melanogaster"

Elizabeth Mehesy (2022). "Western Analysis of DIP-A in Drosophila melanogaster using AntiDIP-A Antibodies"

Nic Stauffer (2020). "Formulation of 3-Dimensional Models for Dip-B mRNA Isoforms A, C, A/C and E in Drosophila melanogaster"

Yifei Duan (2020). "Molecular Genetic Analysis of Dip-A in Drosophila melanogaster"

Steven James: Students in my laboratory discovered a unique protein that governs the stability of the microtubule cytoskeleton. This protein, wdA, is present in all fungi but absent from plants and animals. Mutations in wdA disrupt the microtubule cytoskeleton, causing microtubules to become unstable and leading to a lethal “mitotic catastrophe”. Because wdA is unique to fungi and because it regulates essential cellular processes, it may be a good target for the development of anti-fungal drugs. We recently completed a study using immunoprecipitation + mass spectrometry (IP-MS) to identify candidate proteins that physically associate with the wdA protein, and we are beginning to mine this dataset to uncover the bona fide interactors and thereby reveal the precise function of this regulator of microtubule stability.

Students in my lab are using a variety of approaches to unravel the microtubule-stabilizing function of the wdA protein, including genetic engineering, protein biochemistry, suppressor genetics, bioinformatics, and fluorescence microscopy.

Recent student research:

Brandon Caban (2022): “A surprising paradox involving genetic interactions between the CUE Domain protein mcnC and the wdA microtubule stabilizer in Aspergillus nidulans

Lauren Cooke (2022): “wdA is required for normal microtubule dynamics and nuclear division in Aspergillus nidulans

Olivia Morren (2022): “Quantification of α/β-tubulin pool sizes in Aspergillus nidulans cells lacking the wdA regulator of microtubule stability and cytoskeletal dynamics”

Ashley Gaffey (2022): “A novel fungal β-propeller protein controls microtubule stability in Aspergillus nidulans

Rouwaida Nitiema (2021): “Mutations in two genes relieve defects in a novel fungal microtubule-stabilizing protein” 

Claire Woodward (2020). “Mutations in the wdA regulator of microtubule stability rescues defects in the tubulin assembly pathway” 

Katie Watson (2020). “The conserved C-terminus of the novel wdA ¿-propeller protein is nonessential” 

Recent publication with student co-authors (italized):

James, SW, Jonathan Palmer, Sarah Lea Anglin, Nancy P. Keller, Morgan L. Brown, Matthew R. Dunworth, Sarah G. Francisco, Katherine G. Watson, Breanna Titchen, Alecia Achimovich, Andrew Mahoney Joseph P Artemiou, Kyra G Buettner, Madelyn Class, and Andrew L. Sydenstricker. 2022. A reciprocal translocation involving Aspergillus nidulans snxAHrb1/Gbp2 and gyfA uncovers a new regulator of the G2-M transition and reveals a role in transcriptional repression for the setBSet2 histone H3-lysine-36 methyltransferase. GENETICS 222: 1-21 (October 2022 issue) doi: https://doi.org/10.1093/genetics/iyac130

Ryan Kerney: I am an organismal biologist specializing on the ecology, evolution, and development of amphibians. Current projects include research on the diversity of skeletal development, the formation of “vestigial” structures, symbioses between salamander embryos and green algae, limb development, lung development, and descriptive morphology. While this work is focused on a specific taxonomic group, it touches on many fields within biology.

Check out our lab site for more information: https://sites.google.com/site/kerneylabgc/

Jasper Leavitt (2015). “Examining the initiation of algal cell entry into an embryonic salamander host.”

Kenneth Anderson (2014). “Abundance and establishment of symbiotic bacteria in Plethodon cinereus.”

Matthew Spano (2014). “Bone development in metamorphosing Xenopus tropicalis.”

Recent publications with student co-authors*:

Burns J, Zhang H*, Hill E*, Kim E, Kerney R (2017). Endosymbiont fermentation and host modulation of immunity and nutrient sensing in a vertebrate-alga endosymbiosis revealed by de novo dual-RNA seq. eLife. 2017;6:e22054.

Kerney R, Whatley Z, Rivera S*, Hewitt D. (2017) The prospects of artificial endosymbioses. American Scientist. 105: 36–46.

J. Matthew Kittelberger: As a neurobiologist, I am interested in how the anatomy and physiology of circuits of interconnected nerve cells shape the myriad of fascinating behaviors and perceptual ability of animals and humans. Specifically, my own research focuses on the brain circuits involved in vocal communication, mainly in fish. Students interested in working in my lab could be involved in a variety of projects using different techniques to study the anatomy, the neurochemistry, and/or the electrophysiology of these circuits in the context of how fish produce their courtship and territorial songs. Some of this work recently has focused on the role of dopamine, which has implications for the evolution of dopamine circuits, and their role in regulating motivated /rewarding behaviors across vertebrates. Students should expect to spend at least 2 semesters on their project (with one of these ideally occurring over the summer), and should therefore begin planning for this project no later than the spring semester of their junior year.

Recent publications with student co-authors*:

Allen, A.K.*, Heisler, E.K.*, & J.M. Kittelberger. (2023) Dopamine injections to the midbrain periaqueductal gray inhibit vocal-motor production in a teleost fish. Physiology and Behavior. 263: 114131. doi: https://doi.org/10.1016/j.physbeh.2023.114131.

Goebrecht, G.K.E.*, Kowtoniuk, R.A.*, Kelly, B.G.*, & J.M. Kittelberger. (2014) Sexuallydimorphic expression of tyrosine hydroxylase immunoreactivity in the brain of a vocal teleost fish (Porichthys notatus). Journal of Chemical Neuroanatomy. 56: 13-34.

Jennifer Powell: Cells experience many different types of stress, including the stress of being attacked by pathogens, endogenous stresses such as the production of toxic metabolites or the accumulation of unfolded proteins, and environmental stresses such as changing temperature or salinity. The Powell lab focuses on how cells recognize stress, respond to stress, and integrate signals from multiple stressors. The tiny nematode C. elegans is an outstanding model system to answer these fundamental biological questions using powerful molecular genetic techniques.

The immune response is a special type of cellular stress response to infection by pathogenic microorganisms. Cells must detect the infection so they can respond accordingly. An exciting hypothesis is that cells do so by monitoring for signs of cellular damage that might occur as a result of an infection. One example of damage that does occur is oxidative damage – both from the Reactive Oxygen Species (ROS) produced by pathogens to attack the host cell, and by ROS produced by the host cells to fend off the pathogen. We propose that the host’s immune system may also sense the resulting collateral damage as a trigger to activate or reinforce a defense response.

We also study the response to a brief extreme cold exposure. Following cold stress, we discovered that worms face a decision to allocate resources toward repairing the damage or to provide those resources to their offspring. The choice to transfer lipids to their germline is a reproductive strategy called terminal investment because it results in a survival advantage for the resulting progeny if they experience a subsequent severe cold shock, but it comes at the expense of the life of the parent. In addition to dissecting the molecular mechanisms of cold-induced terminal investment, we are studying the combined effect of cold and osmotic shock on C. elegans.

San Luc (2020). The conserved G-protein coupled receptor FSHR-1 associates BLI-3-mediated oxidative stress with the innate immune response.

Leah Gulyas (2019). Acute cold stress induces terminal investment in C. elegans

Jennifer Giannini (2018). G-protein coupled receptor FSHR-1 displays interconnected roles in stress response and innate immunity. 

Zoe Yeoh (2018). The relationship between fshr-1 and skn-1, two genes involved with the innate immune response in C. elegans

Recent publications with student co-authors*:

Gulyas L* and Powell JR (2019). Predicting the Future: Parental progeny investment in response to environmental stress cues. Frontiers in Cell and Developmental Biology. Jun 19; 7; 115. doi:


Robinson JD*, Powell JR (2016). Long-term recovery from acute cold shock in Caenorhabditis elegans. BMC Cell Biol. Jan 12;17:2. doi: 10.1186/s12860-015-0079-z.

Miller EV*, Grandi LN*, Giannini JA*, Robinson JD*, Powell JR (2015). The conserved G- protein coupled receptor FSHR-1 regulates protective host responses to infection and oxidative stress. PLOS ONE. Sep 11;10(9):e0137403. doi: 10.1371/journal.pone.0137403. 

Angel Solis: The immune system is fighting a constant arms race against the pathogens that seek to circumvent it to establish infection. Every interaction that occurs between microbes and their host offers an opportunity for refinement of the weaponry used in the constant battle of immunity. Although we now have very sophisticated understanding of this process, there are

still many unanswered questions related to how bacteria can subvert host defenses to cause significant pathologies, and how this immune response is appropriately regulated to only respond when absolutely necessary. As such, my lab focuses on understanding both the hostmediated processes that regulate and tailor the inflammatory response, and uncovering novel techniques that bacteria may use to cause disease.

In 2021, the Nobel Prize in Medicine was awarded to research that identified how cells of the nervous system senses its environment. This recognized work showing how neurons express ion channels that only open in response to temperature and physical touch, and how these channels grant mammals the ability to interact with and fully experience their environment. But neurons are not the only system that must be able to sense its environment. The immune system similarly relies on its ability to detect changes in its environment in order to respond appropriately. In fact, immune cells express the exact same ion channels that neurons use to sense their environment and are equally capable of responding to temperature and physical touch. Many parameters of the immunological environment become altered during the course of infection and inflammation. While it is known that immune cells can be regulated by these environmental parameters, how the immune system senses and interacts with its environment is not fully established

In my lab, we are working to discover how immune cells sense their environment, and identify the channels and receptors that allow for this regulation. Such an understanding can allow for a deeper understanding of why some people may have dysregulated inflammation, which contributes to a broad range of human disease. 

For more information visit https://www.thesolislab.com/

Alex Trillo: I use a combination of methods and variety of organisms to answer questions related to Ecology, Behavior and Evolution. Some of the current projects in the lab are:

  1. The influence of eavesdropping bats on mating signal divergence and novel call emergence: We are interested in how eavesdropping predatory bats, such as the frog-eating bat Trachops cirrhosus, respond to sounds produced by their prey, and in how selection imposed by these predators interacts with female call preferences to affect the evolution and maintenance of mating calls. It is well known that the evolution of male mating calls is guided by the sexual preferences of females. But just as females more strongly prefer some call types to others, eavesdropping bats are also more strongly attracted to certain calls. This trade-off, between attractiveness to mates on one hand, and attractiveness to predators on the other, has the potential to shape mating call evolution. We are particularly interested in how this can drive the divergence of mating calls across populations and influence emergence of novel call types within a population. Student researchers conduct playback experiments, presenting a variety of acoustic stimuli to bats in flight chambers and in the field. These studies are carried on at the Smithsonian Tropical Research Institute in Panama during the summer.

  2. Predator and parasite risk transfer in mixed species frog aggregations: We are interested in how mortality risk due to eavesdropping predators, such as the bat Trachops cirrhosus, and parasites, such as the midge Corethrella spp. gets transferred from one prey frog species to another in mixed species aggregations. We investigate whether calling near males of another species makes signalers more or less vulnerable to ‘eavesdroppers’. We are particularly interested in how these prey species interactions drive calling site choice and calling behavior in mixed choruses of tropical frogs. Student researchers that work in this project conduct playback experiments, presenting a variety of acoustic stimuli to bats in flight chambers and in the field. These studies are carried on at the Smithsonian Tropical Research Institute in Panama during the summer.

  3. Pre and post-copulatory sexual selection in insects: Sexually selected traits are often studied one at a time, in isolation from one another, and as if they were the product of a single selective force. In nature, however, multiple sexual traits can interact to affect individual fitness, and multiple selective forces can interact to shape the evolution of a single sexual trait. With these ideas in mind, I simultaneously examine variation in traits used during pre-copulatory processes, such as weapons, and traits used during post-copulatory processes, such as genitalia and testes in insects, such as the tortoise beetle Acromis sparsa, to determine how these primary and secondary sexual traits interact to affect male reproductive success.

I am also willing to supervise motivated students interested on conducting research on behavioral ecology and conservation. Students interested in doing research with me should count on spending more than one semester developing and working on their project.

Samantha Siomko (2017). “Odd one out: Is differential predator attention directed toward rare calls in frog mating mixed-choruses?”

Natalie Pitman (2017). “Assessment of the impact of copper (II) chloride on the multimodal predatory response in zebrafish (Danio rerio).”

István Urcuyo: My research interests are primarily in the field of Marine Biology and Ecology.

Although my current research focuses on the biodiversity of tropical marine invertebrates in Central America, I am also willing to supervise motivated students interested on conducting research on marine environmental problems, marine resources or working away from campus on a marine-related topic. I also have a longstanding interest in cave biology and invertebrate fossils. Students interested in doing research and field work with me should start planning their projects early during their junior year and count on spending two semesters working on their project.

Emily Jankowski (2016). “Effects of thermal stress on nerite grazing activity.”

Jeffrey Romano (2016). “Analyzing the biodiversity of macro invertebrates and abiotic factors in the local p-caves of Franklin County, PA.”

Maria Wanner (2015). “Evaluating the phototaxis of subterranean and surface amphipods.”