Phylogeography

Southeast Asia’s complex geological history and highly variable geography and ecology provide an ideal template for testing the effects of geographic change on phylogenetic processes. Within this fascinating region lies the Philippines, an archipelago straddled by the Sundaland-Eurasian and Philippines sea plates, which has been subjected to numerous geological pressures since the beginning of the Mesozoic. Species assemblages in the region have been further shaped by repeated climatological oscillations, primarily since the Pleistocene, wherein fluctuations in sea level caused dramatic changes in the size, connectivity, and presumably the ecological framework of islands.

A component of my research program is interested in employing statistical tests of phylogenetic topology and population genetic analyses of widespread species to explore whether patterns of diversity can be explained by the geologic history of the region or historically accepted models of diversification. This effort has resulted in the observation of numerous fascinating patterns, all of which indicate that the mechanisms driving diversification in the Philippines are far more complex than previously recognized. Some of these patterns are summarized in several of our recent studies:

Siler, C. D. and R. M. Brown.  2011.  Evidence for repeated acquisition and loss of complex body form characters in an insular clade of southeast Asian semi-fossorial skinks.  Evolution 65:2641-2663.PDF

Siler, C. D., A. C. Diesmos, A. C. Alcala, and R. M. Brown.  2011.  Phylogeny of Philippine slender skinks (Scincidae: Brachymeles) reveals underestimated species diversity, complex biogeographical relationships, and cryptic patterns of lineage diversication. Molecular Phylogenetics and Evolution 59:53-65. PDF