title: Mitochondrial genomes suggest rapid evolution of dwarf California Channel Islands foxes (Urocyon littoralis).
abstract: 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 (~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 ~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 ~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.
authors.affiliation: Department of Anthropology, University of Maryland, College Park, Maryland, United States of America; Program in Human Ecology and Archaeobiology, Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington, District of Columbia, United States of America; Center for Conservation and Evolutionary Genetics, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, District of Columbia, United States of America.
authors.forename: Courtney A
authors.initials: CA
authors.lastname: Hofman
authors.affiliation: Program in Human Ecology and Archaeobiology, Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington, District of Columbia, United States of America.
authors.forename: Torben C
authors.initials: TC
authors.lastname: Rick
authors.affiliation: Center for Conservation and Evolutionary Genetics, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, District of Columbia, United States of America; Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, District of Columbia, United States of America.
authors.forename: Melissa T R
authors.initials: MT
authors.lastname: Hawkins
authors.affiliation: Department of Biology, Graduate Degree Program in Ecology, Colorado State University, Fort Collins, Colorado, United States of America.
authors.forename: W Chris
authors.initials: WC
authors.lastname: Funk
authors.affiliation: Center for Conservation and Evolutionary Genetics, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, District of Columbia, United States of America.
authors.forename: Katherine
authors.initials: K
authors.lastname: Ralls
authors.affiliation: The Nature Conservancy, San Francisco, California, United States of America.
authors.forename: Christina L
authors.initials: CL
authors.lastname: Boser
authors.affiliation: Department of Vertebrate Zoology, Santa Barbara Museum of Natural History, Santa Barbara, California, United States of America.
authors.forename: Paul W
authors.initials: PW
authors.lastname: Collins
authors.affiliation: National Park Service, Channel Islands National Park, Ventura, California, United States of America.
authors.forename: Tim
authors.initials: T
authors.lastname: Coonan
authors.affiliation: Catalina Island Conservancy, Avalon, California, United States of America.
authors.forename: Julie L
authors.initials: JL
authors.lastname: King
authors.affiliation: The Nature Conservancy, San Francisco, California, United States of America.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Morrison
authors.affiliation: Department of Biology, University of New Mexico, Albuquerque, New Mexico, United States of America.
authors.forename: Seth D
authors.initials: SD
authors.lastname: Newsome
authors.affiliation: Migratory Bird Center, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, District of Columbia, United States of America.
authors.forename: T Scott
authors.initials: TS
authors.lastname: Sillett
authors.affiliation: Center for Conservation and Evolutionary Genetics, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, District of Columbia, United States of America.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Fleischer
authors.affiliation: Center for Conservation and Evolutionary Genetics, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, District of Columbia, United States of America; Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, District of Columbia, United States of America.
authors.forename: Jesus E
authors.initials: JE
authors.lastname: Maldonado
mesh_terms: D000818:Animals; D002140:California; D016000:Cluster Analysis; D019143:Evolution, Molecular; D005589:Foxes / Q000145:classification / Q000235:genetics*; D014644:Genetic Variation; D054629:Genome, Mitochondrial; D006239:Haplotypes; D062312:Islands; D008969:Molecular Sequence Data; D010802:Phylogeny