Research Abstracts Online
January 2009 - March 2010
University of Minnesota Twin Cities
College of Biological Sciences
Department of Ecology, Evolution, and Behavior
PI: F. Keith Barker
Phylogeny of New World Passerine Birds: Inferring Evolutionary History From Molecular Data
The history of the New World fauna is an excellent arena for understanding the interplay of isolation, dispersal, orogeny, and ecology on organismal diversification at the phenotypic and species level. For example, extremely important insights have been gained by studying the fossil record of New World mammals, which has revealed the biogeographic origins of major mammalian groups, the directionality and timing of their dispersal between North and South America, and the fundamental asymmetry in their subsequent evolutionary success in these regions. Unfortunately, not all groups have such a rich fossil record, making it necessary to infer these events based on other data, which include the current distributions of and phylogenetic relationships among living forms. New World passerine birds are of particular interest in this regard, because they are quite diverse in terms of morphologies, ecology, and species number. The goal of this study is to infer phylogenetic relationships among these diverse forms in order to address similar questions that have been addressed in mammals: where did they come from, which paths have they taken once they arrived, how have they adapted to local conditions, and what determines why some lineages are so much more diverse than others? To infer these phylogenies, analyses of large genetic data sets (hundreds of species for thousands of base pairs) are necessary. Only recently have methods based on Markov chain Monte Carlo and genetic algorithms been developed that can analyze large data sets with evolutionary realistic models. This research project focuses on analyses using these methods, as well as validating their performance using simulation.