I am broadly interested in integrating studies of natural history with molecular genomics and phylogenetics. Specifically, I aim to elucidate causal genetic mechanisms underlying novel traits, characterize phenotypic diversification at macro and micro-evolutionary scales, and identify factors that promote and constrain biodiversity. Research in my lab often involves merging fieldwork, labwork, and bioinformatics to get at the molecular mechanisms and evolutionary forces underlying adaptive traits. Below I detail several of my ongoing research projects.
- Over the last 50 million years, poison frogs (family Dendrobatidae) have evolved to sequester alkaloids from diminutive arthropod prey three independent times, paired with parallel changes in metabolism, skin morphology, diet, coloration, behavior, and neurophysiology. Thus, I study genomics of poison frogs to identify mechanisms underlying the origins and diversification of complex novel phenotypes.
- Evolutionary transitions underlying large-scale phenotypic change (as in the poison frogs) are difficult to study because they often occur over millions of years. However, the fruit fly has a short generation time and a small genome. Thus, I am using experimental evolution to evolve toxin-sequestering fruit flies. Evolutionary changes in the fruit fly genome, transcriptome, and physiology will generate a model of how chemical defense arises that will inform studies in non-model organisms.
- The evolution of acquired neurotoxic defenses requires myriad changes in an organism's nervous system and physiology. Using target-bait capture, I am sequencing genes involved in these sensory and physiological processes in three clades of aposematic frogs. Behavioral experiments paired with physiological assays will evaluate how identified genetic changes produce novel phenotypes.
Santos, JC, RD Tarvin, LA O'Connell, D Blackburn, and LA Coloma. 2018. Diversity within diversity: Transcriptomic characterization of eukaryotic symbionts in poison frogs. Molecular Phylogenetics and Evolution 125: 40–50.
Tarvin*, RD, CM Borghese*, W Sachs, JC Santos, L Yu, LA O'Connell, DC Cannatella, RA Harris, and HH Zakon. 2017. Interacting amino acid replacements allow poison frogs to evolve epibatidine resistance. Science 357: 1261–1266.
Tarvin*, RD, E Powell*†, JC Santos, SR Ron, and DC Cannatella. 2017. The birth of aposematism: High phenotypic divergence and low genetic diversity in a young clade of poison frogs. Molecular Phylogenetics and Evolution 109: 283–295.
Tarvin, RD, JC Santos, LA O’Connell, HH Zakon, and DC Cannatella. 2016. Convergent substitutions in sodium channel suggest multiple origins of toxin resistance in poison frogs. Molecular Biology and Evolution 33:1068-1081.
Santos*, JC, RD Tarvin*, and LA O'Connell*. 2016. A review of chemical defense in poison frogs (Dendrobatidae): Ecology, pharmacokinetics and autoresistance. In: Schulte, BA, TE Goodwin, MH Ferkin, editors. Chemical Signals in Vertebrates 13. Switzerland: Springer International Publishing. p. 305-337.
Tarvin, RD, CS Bermúdez, VS Briggs, and KM Warkentin. 2015. Carry-over effects of size at metamorphosis in red-eyed treefrogs: higher survival but slower growth of larger metamorphs. Biotropica 47:218-226.
Tarvin, RD, P Peña, and SR Ron. 2014. Changes in population size and survival in Atelopus spumarius (Anura: Bufonidae) are not correlated with chytrid prevalence. Journal of Herpetology 48:291-297.
Muñoz, M, NG Crawford, TJ McGreevy, NJ Messana, RD Tarvin, LJ Revell, RM Zandvliet, JM Hopwood, E Mock, AL Schneider, and CJ Schneider. 2013. Divergence in coloration and ecological speciation in the Anolis marmoratus species complex. Molecular Ecology 22:2668-2682.
*Authors contributed equally