Mitochondrial Genomes Suggest Rapid Evolution of Dwarf California Channel Islands Foxes (Urocyon littoralis)

作者:Hofman Courtney A*; Rick Torben C; Hawkins Melissa T R; Funk W Chris; Ralls Katherine; Boser Christina L; Collins Paul W; Coonan Tim; King Julie L; Morrison Scott A; Newsome Seth D; Sillett T Scott; Fleischer Robert C; Maldonado Jesus E
来源:PLos One, 2015, 10(2): e0118240.
DOI:10.1371/journal.pone.0118240

摘要

Island endemics are typically differentiated from their mainland progenitors in behavior, morphology, and genetics, often resulting from long-term evolutionary change. To examine mechanisms for the origins of island endemism, we present a phylogeographic analysis of whole mitochondrial genomes from the endangered island fox (Urocyon littoralis), endemic to California's Channel Islands, and mainland gray foxes (U. cinereoargenteus). Previous genetic studies suggested that foxes first appeared on the islands > 16,000 years ago, before human arrival (similar to 13,000 cal BP), while archaeological and paleontological data supported a colonization > 7000 cal BP. Our results are consistent with initial fox colonization of the northern islands probably by rafting or human introduction similar to 9200-7100 years ago, followed quickly by human translocation of foxes from the northern to southern Channel Islands. Mitogenomes indicate that island foxes are monophyletic and most closely related to gray foxes from northern California that likely experienced a Holocene climate-induced range shift. Our data document rapid morphological evolution of island foxes (in similar to 2000 years or less). Despite evidence for bottlenecks, island foxes have generated and maintained multiple mitochondrial haplotypes. This study highlights the intertwined evolutionary history of island foxes and humans, and illustrates a new approach for investigating the evolutionary histories of other island endemics.

  • 出版日期2015-2-25