|
Research interests Research in my lab examines how the ecological landscape shapes biological diversification. We approach this issue through studies in ecology, behavior, evolution, genetics, and phylogenetics. For the past several years, my research system has been a group of amphipod crustaceans in the genus Hyalella. In North America, Hyalella form a species complex with some remarkable properties. First, widespread species tend to occur as one of two ecomorphs ( photo, right), with morphological and life history traits strongly tied to the ecological conditions of their habitat. Second, the multiple species within each ecomorph are sometimes separated by substantial molecular genetic evolution, making their high degree of phenotypic similarity all the more remarkable. Some of the questions we ask in our research are How does habitat ecology shape the phenotypes of the ecomorphs?, How are mating behavior and sexual selection influenced by the ecological factors that drive the ecomorph divergence?, What is the phylogenetic structure of Hyalella diversification, and what role have ecological process played in speciation? |
|
Interested in joining my lab? I am always happy to talk with students interested graduate opportunities in my lab. Please send me an email, and I will let you know what we are doing currently, and what opportunities are available. Photo: John White and Rickey Cothran are current graduate students |
|
Selected Publications Wellborn, G. A., and R. D. Cothran. 2005. Evolution and ecology of mating behavior in freshwater amphipods. In E. Duffy and M. Thiel, editors. Evolutionary ecology of social and sexual systems: crustaceans as model organisms. Cambridge University Press. (in press) Wellborn, G. A., and S. Bartholf. 2005. Ecological context and the interaction of natural and sexual selection in two amphipod species. Oecologia 143: 308-316. Wellborn, G. A., R. D. Cothran, and S. Bartholf. 2005. Life history and allozyme diversification in regional ecomorphs of the Hyalella azteca (Crustacea: Amphipoda) species complex. Biological Journal of the Linnean Society 84: 161-175. Wellborn, G. A., and R. D. Cothran. 2004. Phenotypic similarity and differentiation among sympatric cryptic species in a freshwater amphipod species complex. Freshwater Biology 49:1-13. Cothran, R. D. 2004. Precopulatory mate guarding affects predation risk in two freshwater amphipod species. Animal Behaviour 68: 1133-1138. Wellborn, G. A. 2002 Tradeoff between competitive ability and antipredator adaptation in a freshwater amphipod species complex. Ecology 83:129-136. McPeek, M. A., and G. A. Wellborn. 1998. Genetic variation and reproductive isolation among phenotypically divergent amphipod populations. Limnology & Oceanography 43:1162-1169. Wellborn, G. A., D. K. Skelly, and E. E. Werner. 1996. Mechanisms creating community structure across a freshwater habitat gradient. Annual Review of Ecology and Systematics 27:337-363. Wellborn, G. A. 1995. Determinants of reproductive success in freshwater amphipod species differing in body size and life history. Animal Behaviour 50:353-363. Wellborn, G. A. 1994. Size-biased predation and the evolution of prey life histories: a comparative study of freshwater amphipod populations. Ecology 75:2104-2117. |
