DISSERTATION RESEARCH: A Phylogenetic Context for the extent of Genomic Introgression between Spotted and Barred Owls

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

The ranges of Barred and Spotted Owls have recently come in contact, and they now broadly co-occur and hybridize across western North America. Seven of the other twenty-one wood owl species also hybridize. This project will use new genomic sequencing methods to infer the evolutionary relationships of these owl species. It also will determine whether the species that hybridize recently diverged or whether they diverged elsewhere geographically and have recently come into contact. In addition, this research will provide information on how best to cost-effectively unlock the genomic resources of museum specimen collections. Genome-wide data will produce a deeper understanding of the biogeographic history and genetic divergence of these two competing and hybridizing owl species and will help elucidate the genetic implications of modern species range shifts. This project will also train one full-time graduate student in laboratory and analysis techniques, including the generation and interpretation of genomic data. This project will use a previously assembled Spotted Owl (Strix occidentalis) genome as a resource to analyze breeding between Spotted and Barred Owls at a genome-wide scale. Researchers will employ sequence-capture methodology to obtain DNA sequences of markers distributed across the genome for 21 species within the genus Strix. These data will be used to construct a multilocus phylogeny to address questions concerning the following: 1) the phylogenetic relationship of the Spotted and Barred Owl, 2) the evolutionary and biogeographic history of currently hybridizing Strix species, and 3) which of two different sequence capture methods (ultra conserved elements and restriction enzyme digest markers) captures the most informative data from degraded DNA isolated from museum specimens. Utilizing the assembled reference Spotted Owl genome, this research will identify the precise genomic locations of the regions captured and examined in their analyses, and determine whether the instances of interspecific hybridization in other Strix species occur between recently diverged taxa or whether the hybridizing taxa diverged elsewhere geographically and have newly contacted.