Evolutionary Ecology of Galápagos Lava Lizards (Microlophus spp.)
A central goal of evolutionary biology is to understand the origin and maintenance of genetic and phenotypic diversity. Studies of populations resident on oceanic islands have provided critical insight into these processes. Galápagos lava lizards are a group that lends itself to rigorous evolutionary study in this tradition. Populations of lava lizards are distributed across an array of islands and islets that are geographically proximate and share a well-defined geological history. Considerable variation in morphology, life history, ornamentation and physiological performance exists within and among these populations. We have shown that gene flow is unlikely to limit phenotypic divergence within a small island that exhibits a marked shift in habitat structure. Meanwhile, genetic drift in isolation is strongly implied in populations that were fragmented when sea levels rose following glacial melting at the end of the Pleistocene. These results suggest that an interaction between drift and selection is likely to have shaped the recent diversification of these lizards.
Jordan, M.A. and H.L. Snell. 2008. Historical fragmentation and genetic drift in populations of Galápagos lava lizards (Microlophus albemarlensis complex). Molecular Ecology 17:1224-1237.
Jordan, M.A., H.L. Snell, H.M. Snell, and W.C. Jordan. 2005. Phenotypic divergence despite high levels of gene flow in Galápagos lava lizards (Microlophus albemarlensis). Molecular Ecology 14:859-867.
Jordan, M.A., R.L. Hammond, H.L. Snell, H.M. Snell, and W.C. Jordan. 2002. Isolation and characterization of microsatellite loci from Galápagos lava lizards (Microlophus spp.). Molecular Ecology Notes 2:349-351.
Jordan, M.A. and H.L. Snell. 2002. Life history trade-offs and phenotypic plasticity in the reproduction of Galápagos lava lizards (Microlophus delanonis). Oecologia 130:44-52.