title: Evidence of Subdivisions on Evolutionary Timescales in a Large, Declining Marsupial Distributed across a Phylogeographic Barrier.
abstract: Major prehistoric forces, such as the climatic shifts of the Pleistocene, can remain visible in a species' population genetics. Inference of refuges via genetic tools is useful for conservation management as it can identify populations whose preservation may help retain a species' adaptive potential. Such investigation is needed for Australia's southern hairy-nosed wombat (Lasiorhinus latifrons), whose conservation status has recently deteriorated, and whose phylogeographic history during the Pleistocene may be atypical compared to other species. Its contemporary range spans approximately 2000 km of diverse habitat on either side of the Spencer Gulf, which was a land bridge during periods of Pleistocene aridity that may have allowed for migration circumventing the arid Eyrean barrier. We sampled from animals in nearly all known sites within the species' current distribution, mainly using non-invasive methods, and employed nuclear and mitochondrial DNA analyses to assess alternative scenarios for Pleistocene impacts on population structure. We found evidence for mildly differentiated populations at the range extremes on either side of Spencer Gulf, with secondary contact between locations neighbouring each side of the barrier. These extreme western and eastern regions, and four other regions in between, were genetically distinct in genotypic clustering analyses. Estimates indicate modest, but complex gene flow patterns among some of these regions, in some cases possibly restricted for several thousand years. Prior to this study there was little information to aid risk assessment and prioritization of conservation interventions facilitating gene flow among populations of this species. The contributions of this study to that issue are outlined.
authors.affiliation: School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, Australia.|University of New South Wales, Kensington, New South Wales, Australia.
authors.forename: Deryn L
authors.initials: DL
authors.lastname: Alpers
authors.affiliation: School of Biological Sciences, Monash University, Clayton, Victoria, Australia.|School of Forestry, Northern Arizona University, Flagstaff, Arizona, United States of America.
authors.forename: Faith M
authors.initials: FM
authors.lastname: Walker
authors.affiliation: School of Biological Sciences, Monash University, Clayton, Victoria, Australia.
authors.forename: Andrea C
authors.initials: AC
authors.lastname: Taylor
authors.affiliation: School of Biological Sciences, Monash University, Clayton, Victoria, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Sunnucks
authors.affiliation: University of South Australia, Adelaide, South Australia, Australia.
authors.forename: Steven
authors.identifier: http://orcid.org/0000-0002-0085-2014
authors.initials: S
authors.lastname: Bellman
authors.affiliation: School of Biological Sciences, Monash University, Clayton, Victoria, Australia.|Centre for eResearch and Digital Innovation, Federation University Australia, Ballarat, Victoria, Australia.
authors.forename: Birgita D
authors.initials: BD
authors.lastname: Hansen
authors.affiliation: University of New South Wales, Kensington, New South Wales, Australia.|Murdoch University Cetacean Research Unit, Murdoch University, Murdoch, Western Australia, Australia.
authors.forename: William B
authors.initials: WB
authors.lastname: Sherwin
mesh_terms: D000818:Animals; D005075:Biological Evolution; D015139:Blotting, Southern; D016000:Cluster Analysis; D045303:Cytochromes b / Q000235:genetics; D004272:DNA, Mitochondrial / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D017753:Ecosystem; D014644:Genetic Variation; D006239:Haplotypes; D008394:Marsupialia / Q000145:classification / Q000235:genetics*; D018895:Microsatellite Repeats / Q000235:genetics; D058974:Phylogeography; D012150:Polymorphism, Restriction Fragment Length; D013021:South Australia
chemical_list: D004272:DNA, Mitochondrial; D045303:Cytochromes b