Nature's genes in space and time: using DNA to uncover the history and formation of biodiversity.

Abstract

Modern science is tasked with explaining biological diversity: where it is, where it comes from, and how it evolves. Molecular tools have revolutionized this endeavor and given us the ability to peer into the evolutionary past like never before. Drawing on examples from the birds and mammals of East Asia, I present a progression of methods for uncovering the history and formation of species using molecular approaches. Because the characterization of diversity must necessarily precede the study of diversity, I begin in Chapter 1 with a species delimitation study aimed at resolving evolutionary lineages. I conclude that fixed character differences are better indicators of lineage limits than statistical approaches and that both morphological and molecular characters may be necessary to reveal lineages when divergence is recent. In Chapter 2 I describe the evolutionary history of a single-species in which I found evidence for a recent range-wide demographic expansion. This particular example demonstrates how phylogeography and ecological niche modeling can reciprocally illuminate aspects of evolutionary history. Finally, in Chapter 3 I discuss a comparative study of the evolutionary histories of multiple co-distributed species. Comparative studies reveal the generalities involved in evolution and allow us to discern the major drivers of biological diversity.