DISSERTATION RESEARCH: The Evolution of Male Choice and Implications for Speciation by Reinforcement in the Hawaiian Cricket Genus Laupala (Family: Trigonidiinae)

University Of Maryland, College Park, College Park MD

Investigators

Abstract

In the Hawaiian cricket genus Laupala, genetic and behavioral evidence suggest that reinforcement, a process whereby natural selection against hybrids results in better species discrimination among the parental females, has played a substantial role in speciation. Reinforcement is an interesting problem in evolutionary biology because it provides an explanation for sympatric speciation, and because relatively few cases have been documented; Laupala provides a particularly attractive case study because it appears that changes in male behavior due to the high costs of spermatophore production have caused the end result of reinforcement to be a shift in male, rather than female, choice. I propose to test if this hypothesis by: (1) creating a population-level phylogeny in order to define species boundaries and identify areas of reinforcement, (2) evaluating male costs by measuring mating refractory periods and limits on spermatophore production, and (3) testing for behavioral isolation between sympatric and allopatric species pairs, using a traditional reinforcement assay. Overall, this study proposes to uncover a novel and potentially significant way of investigating both reinforcement and male choice, and may provide another explanation for how new species can form in areas of contact. Understanding speciation is key to a greater understanding of evolution and our role in it. This work is valuable because it provides for undergraduate and graduate training, and moreover, because the broader impacts will serve to not only enhance our appreciation for the processes of speciation, but may help us better appreciate how to preserve delicate Hawaiian ecosystems. It involves the training of women in the sciences.