DISSERTATION RESEARCH: Speciation Genomics: Expanded Sampling of a Remarkable Avian Radiation

Trustees Of Boston University, Boston

Investigators

Abstract

Speciation, the evolution of new, distinct species from a single ancestral population, is the fundamental process generating the earth?s biodiversity. This project focuses on a group of twelve finch species called ?munias? that represent one of the most extraordinary examples of rapid speciation in birds. The twelve species, most living in New Guinea or surrounding islands, are nearly identical genetically, but have evolved an astounding diversity of plumage colors and patterns, as well as differences in bill size. This project combines the first significant field research on these birds (the grant specifically supports fieldwork in the Trans Fly region of Papua New Guinea, where two additional species will be sampled) with modern genome sequencing technology to reconstruct the evolutionary history of these species and determine the number and identity of genes that are responsible for differences among species. Given their morphological diversity and recent origin, the munias provide an exceptional opportunity to advance the new field of speciation genomics, which seeks to understand the patterns of genetic change responsible for the evolution of new species. The research will test the hypothesis that natural selection on a small number of genes is sufficient to generate new species, challenging a classic model of gradual genome-wide divergence. As such, the results may overturn commonly held assumptions about the nature of species and speciation. The research will also advance our understanding of the evolution of plumage coloration in birds generally and will provide critical data for making informed decisions on priorities for biodiversity conservation.