Environmental correlates of genetic variation in the invasive and largely panmictic European starling in North America

Autor: Scott J. Werner, Natalie R. Hofmeister, Irby J. Lovette
Rok vydání: 2020
Předmět:
DOI: 10.22541/au.159741548.88179477
Popis: Populations of invasive species that colonize and spread in novel environments may differentiate both through demographic processes and local selection throughout the genome. European starlings (Sturnus vulgaris) were introduced to New York in 1890 and subsequently spread throughout North America, becoming one of the most widespread and numerous bird species on the continent. Genome-wide comparisons across starling individuals and populations can identify demographic and/or selective factors that facilitated this rapid and successful expansion. We investigated patterns of genomic diversity and differentiation using reduced-representation genome sequencing (ddRADseq) of 17 starling populations. Consistent with this species’ high dispersal rates and rapid expansion history, we found low genome-wide differentiation and few FST outliers even at a continental scale. Despite starting from a founding population of approximately 180 individuals, North American starlings do not seem to have undergone a detectable genetic bottleneck: they have maintained an extremely large effective population size since introduction. We find more than 200 variants that correlate with temperature and/or precipitation. Genotype-environment associations (but not outlier scans) identify these SNPs against a background of negligible genome- and range-wide divergence. Such variants fall in the coding regions of genes associated with metabolism, stress, and neurological function. This evidence for incipient local adaptation in North American starlings suggests that it can evolve rapidly even in wide-ranging and evolutionarily young populations. This survey of genomic signatures of expansion in North American starlings is the most comprehensive to date and complements ongoing studies of world-wide local adaptation in these highly dispersive and invasive birds.
Databáze: OpenAIRE