Meeting Abstract
Human movement and trade have greatly accelerated the rate of biological invasions across the globe. Naturalized monk parakeet (Myiopsitta monachus) populations have established in multiple urban areas in the Northern hemisphere as a consequence of the pet trade. These populations present an ideal natural experiment for investigating the complex relationship between natural selection, genetic drift and adaptation following invasion. Previous research shows low neutral genetic diversity among naturalized populations compared to native South American populations. These patterns of low genetic diversity in the naturalized range suggest that either naturalized populations are adapting to selective regimes imposed by new environments, or populations are experiencing genetic drift, including population bottlenecks and founder effects. I am distinguishing between these hypotheses using a genome-wide approach, RAD-sequencing, to identify genes under selection among naturalized and native populations. My results show differentiation between native and naturalized populations, and overall, similar patterns of differentiation to a previous population genetics study. As diseases are among the foremost selection pressures experienced by colonizing populations, I am also working on a candidate gene approach targeted to immune-related major histocompatibility complex (MHC) and toll-like receptor (TLR) genes. This study of genetic adaptation on a genomic scale in a vertebrate invader will broaden our understanding of genetic change associated with biological invasions, and will set the stage for studies of phenotypic adaptation.
