EAGER: RUI: The genomic architecture of speciation in an avian hybrid zone

Occidental College, Los Angeles CA

Investigators

Abstract

This study seeks to address how the genomes of different birds respond to hybridization and what keeps them distinct. The two forms of the Western Scrub-Jay, one found in coastal California and the other in the interior United States, have different plumage colors and different bill shapes that are adapted to local resources. This study will look at an area of contact between them to address two important questions that are currently intensely debated in the field of evolutionary theory: (1) whether genetic divergence on the sex chromosomes plays an outsized role in keeping species separate; and (2) whether genomic divergence tends to accumulate in just a few places in the genome, or whether divergence is more evenly spread out throughout the genome. To accomplish this, the researchers will use novel methods for sequencing large subsets of the genomes of many individuals found inside and outside a contact zone near Lake Tahoe. Understanding how species remain distinct despite the fact that they sometimes interbreed and exchange genes is an important basic question in evolutionary biology bearing on how and why biodiversity is generated. It is also important from the standpoint of protecting and managing our country's existing wealth of biodiversity, because there are many natural and human-mediated cases of hybridization between economically important species. This research will lead to a better understanding of how the genome responds to hybridization, and what keeps species distinct.