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We study how animals have changed their physiology to overcome challenges in their environment. Amphibians in particular have made drastic changes to their physiology in different ecological contexts. We currently have several projects that focus on innovative physiological solutions to predation challenges.

Chemical Ecology


O'Connell Lab Chemical Ecology Logo

Lab member: Nora Moskowitz

How does variation in diet and habitat influence poison frog toxicity? Some poison frog species carry toxic chemicals to avoid predation. Poison frogs do not make their own toxins, but rather sequester toxins from the ants and mites in their diet. Thus, the frogs' ability to defend themselves is tightly linked to their environment. We are studying the trophic ecology of poison frog toxicity by linking together information about habitat, diet, and toxins across many populations and species. Collaborators: Luis Coloma (Centro Jambatu) and David Donoso (Escuela Politécnica Nacional)


Physiology of Chemical Defenses

Lab member: Aurora Alvarez-Buylla

How do frogs sequester toxic small molecules from their diet to serve as chemical defenses? Poison frogs have developed special physiological mechanisms that allow them to uptake and store lipophilic alkaloids from their diet. To accomplish this, they need proteins for alkaloid transport throughout the body and modifications to ion channels that allow toxin resistance. We are studying the evolution of toxin sequestration from an organismal physiology perspective to characterize the toxin uptake system in poison frogs. Collaborators: Luis Coloma (Centro Jambatu) and Justin Du Bois (Stanford University)

Glass Frog Transparency


O'Connell Lab Transparency Logo

Lab member: Jesse Delia

What is the genetic basis and adaptive function of glass frog transparency?  Glass frogs are unique among terrestrial vertebrates in their transparency. We are sequencing the genome of the Northern Glass Frog (Hyalinobatrachium fleischmanni) and using comparative genomics to gain insights into the evolution of transparency. We are conducting field studies to determine the adaptive function of ventral transparency. Collaborators: Juan Manuel Guayasamin (Universidad San Francisco de Quito) and Sonke Johnsen (Duke University)