title: Range-wide multilocus phylogeography of the red fox reveals ancient continental divergence, minimal genomic exchange and distinct demographic histories.
abstract: Widely distributed taxa provide an opportunity to compare biogeographic responses to climatic fluctuations on multiple continents and to investigate speciation. We conducted the most geographically and genomically comprehensive study to date of the red fox (Vulpes vulpes), the world's most widely distributed wild terrestrial carnivore. Analyses of 697 bp of mitochondrial sequence in ~1000 individuals suggested an ancient Middle Eastern origin for all extant red foxes and a 400 kya (SD = 139 kya) origin of the primary North American (Nearctic) clade. Demographic analyses indicated a major expansion in Eurasia during the last glaciation (~50 kya), coinciding with a previously described secondary transfer of a single matriline (Holarctic) to North America. In contrast, North American matrilines (including the transferred portion of Holarctic clade) exhibited no signatures of expansion until the end of the Pleistocene (~12 kya). Analyses of 11 autosomal loci from a subset of foxes supported the colonization time frame suggested by mtDNA (and the fossil record) but, in contrast, reflected no detectable secondary transfer, resulting in the most fundamental genomic division of red foxes at the Bering Strait. Endemic continental Y-chromosome clades further supported this pattern. Thus, intercontinental genomic exchange was overall very limited, consistent with long-term reproductive isolation since the initial colonization of North America. Based on continental divergence times in other carnivoran species pairs, our findings support a model of peripatric speciation and are consistent with the previous classification of the North American red fox as a distinct species, V. fulva.
authors.affiliation: Mammalian Ecology and Conservation Unit, Veterinary Genetics Laboratory, University of California, One Shields Avenue/Old Davis Road, Davis, CA, 95616-8744, USA.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Statham
authors.forename: James
authors.initials: J
authors.lastname: Murdoch
authors.forename: Jan
authors.initials: J
authors.lastname: Janecka
authors.forename: Keith B
authors.initials: KB
authors.lastname: Aubry
authors.forename: Ceiridwen J
authors.initials: CJ
authors.lastname: Edwards
authors.forename: Carl D
authors.initials: CD
authors.lastname: Soulsbury
authors.forename: Oliver
authors.initials: O
authors.lastname: Berry
authors.forename: Zhenghuan
authors.initials: Z
authors.lastname: Wang
authors.forename: David
authors.initials: D
authors.lastname: Harrison
authors.forename: Malcolm
authors.initials: M
authors.lastname: Pearch
authors.forename: Louise
authors.initials: L
authors.lastname: Tomsett
authors.forename: Judith
authors.initials: J
authors.lastname: Chupasko
authors.forename: Benjamin N
authors.initials: BN
authors.lastname: Sacks
mesh_terms: D000483:Alleles; D000818:Animals; D001499:Bayes Theorem; D002467:Cell Nucleus / Q000235:genetics; D016000:Cluster Analysis; D004272:DNA, Mitochondrial / Q000235:genetics; D019143:Evolution, Molecular; D005589:Foxes / Q000235:genetics*; D051456:Gene Flow; D005819:Genetic Markers; D014644:Genetic Variation; D005828:Genetics, Population; D008877:Middle East; D008957:Models, Genetic; D009656:North America; D010802:Phylogeny; D058974:Phylogeography; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial; D005819:Genetic Markers
keywords: Pleistocene; Vulpes fulva; Vulpes vulpes; Y-chromosome; global phylogeography; mitochondrial DNA; nuclear DNA; speciation