High levels of intraspecific genetic divergences revealed fo
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TitleHigh levels of intraspecific genetic divergences revealed for Antarctic springtails: evidence for small-scale isolation during Pleistocene glaciationAbstractWe examined levels of genetic variability within and among populations of three Antarctic springtail species (Arthropoda: Collembola) and tested the hypothesis that genetic divergences occur among glacially-isolated habitats. The study was conducted in southern Victoria Land, Ross Dependency, Antarctica, and samples were collected from locations in the vicinity of the Mackay Glacier. We analyzed mtDNA (cytochrome c oxidase subunit I; COI) sequence variability for 97 individuals representing three species (Gomphiocephalus hodgsoni, N = 67; Cryptopygus nivicolus, N = 20; and Antarcticinella monoculata, N = 8). Haplotype diversity and genetic divergences were calculated and used to indicate population variability and also to infer divergence times of isolated populations using molecular clock estimates. Two of the three species showed high levels of genetic divergence. Gomphiocephalus hodgsoni, a widespread and common species, showed 7.6% sequence divergence on opposite sides of the Mackay Glacier. The more range restricted C. nivicolus showed 4.0% divergence among populations. The third species, A. monoculata, was found in only one location. Molecular clock estimates based on sequence divergences suggest that populations separated within the last 4 Mya. We conclude that habitat fragmentation resulting from Pliocene (5 Mya) and Pleistocene (2 Mya to 10 Kya) glaciations has promoted and maintained high levels of diversity among isolated springtail populations on relatively small spatial scales. The region surrounding the Mackay Glacier is likely to have provided refugia for springtail populations during glacial maxima and remains an area of high genetic and species diversity for Collembola within the Ross Sea region. Copyright 2016 The Linnean Society of LondonAcknowledgementsWe are grateful to three anonymous reviewers for their thoughtful and constructive suggestions that improved the quality of the manuscript. We thank M. Knox, C. Beet, U. Nielsen, D. Wall, and D. McKnight (US Antarctic LTER Programme) for helpful advice and/or assistance in the field/laboratory, as well as members of the Pacific Biosystematics Research group (University of Waikato) for discussion and comments during manuscript preparation. Glen Stichbury provided help preparing Fig. 1, which was derived from the SCAR Antarctic Digital Database and the Landsat Image Mosaic of Antarctica (LIMA) project. Financial support was provided to KRB through a New Zealand Post scholarship administered by Antarctica New Zealand, a University of Waikato Masters Research Scholarship, and The International Centre for Terrestrial Antarctic Research (ICTAR) Young Investigator Award. Field work was supported by Antarctica New Zealand and the US National Science Foundation through the McMurdo LTER NSF OPP grant 1115245. Sequencing at the Biodiversity Institute of Ontario was supported by funding from the Government of Canada through Genome Canada and the Ontario Genomics Institute.
1st AuthorBennett, K.AuthorBennett, K.Hogg, I.Adams, B.Hebert, P.Year2016JournalBiological Journal of the Linnean SocietyVolume119Number1Pages166-178DOI10.1111/bij.12796URLhttps://www.scopus.com/inward/recor.....2d79783045f304fd264527b18KeywordsArthropodaCollembolaCryptopygusGomphiocephalus hodgsoniMya, rank5Author KeywordsCollembolaglaciationpopulation geneticsrefugiaRoss Sea regionspringtailsProgrammeK024 - Invertebrates on the edge: Assessing Mackay Gl as an ecotone for tracking biological responses to climate changes
TypeArticleCitationBennett, K., Hogg, I., Adams, B. and Hebert, P. (2016). High levels of intraspecific genetic divergences revealed for Antarctic springtails: evidence for small-scale isolation during Pleistocene glaciation. Biological Journal of the Linnean Society, 119(1): 166-178
Antarctica NZ (29th Nov 2018). High levels of intraspecific genetic divergences revealed fo . In Website Antarctica NZ. Retrieved 26th Feb 2021 18:29, from https://adam.antarcticanz.govt.nz/nodes/view/63392