78.4 Friday, Jan. 6 Ecological causes of the joint evolution of life history and morphology during a post-Pleistocene radiation of Bahamas mosquitofish (Gambusia hubbsi) RIESCH, Rüdiger*; MARTIN, Ryan A; LANGERHANS, R Brian; NC State University, Raleigh; NC State University, Raleigh; NC State University, Raleigh firstname.lastname@example.org
Predation is a well-known driver for morphological and life-history evolution across various taxa and in particular in livebearing fishes (Poeciliidae). Bahamas mosquitofish (Gambusia hubbsi) inhabiting blue holes are known to have diverged in body shape between localities with and without bigmouth sleeper (Gobiomorus dormitor), a piscivorous fish. Here, we examined life histories of G. hubbsi across 14 blue holes, and found clear evidence for the expected life-history divergence as a response to predation, but there was also significant divergence between populations within both low- and high-predation localities in both sexes (a phenomenon also known to exist for body shape). Using model selection we investigated the role of other environmental factors (e.g., population density, primary productivity, salinity, sex ratio) on life-history and body-shape evolution within and between predator regimes. Finally, we investigated the co-variation between life histories and morphologies at the individual, population, and predation-regime levels.