Vagrants and Variability - Evolution on Remote Islands

Remote islands have been heralded as "natural laboratories", with some spectacular cases of rapid evolution and proliferation of species. One of the most puzzling features of the high diversity of species on remote islands is that they almost certainly arose from one, or very few colonizers. How was variability regained after such genetic bottlenecks, and how did it give rise to ecological diversity? I will be looking at organisms, in particular spiders and other invertebrates, that have naturally (before humans) colonized the world's most remote locales, and will discuss patterns of colonization and how the organisms changed when they reached these islands. Which groups have proliferated, how predictable is that, and to what extent do the same forms evolve repeatedly during the course of diversification? I will also consider how patterns of colonization to these islands have been altered with the arrival of humans and consider why these areas have come to be known as hotspots of extinction. I will speculate as to how we might expect biodiversity on these island hotspots to change as we go into the future.

Speaker: Rosemary Gillespie, UC Berkeley

Room 100