Galina Gussarova1, Geraldine A Allen2, Yulia Mikhaylova3, Laurie J McCormick2, Virginia Mirré4, Kendrick L Marr5, Richard J Hebda6, Christian Brochmann4. 1. Natural History Museum, University of Oslo, P.O. Box 1172 Blindern, NO-0318 Oslo, Norway Department of Botany, St. Petersburg State University, St. Petersburg 199034, Russia galina.gusarova@nhm.uio.no. 2. Department of Biology, University of Victoria, PO Box 1700 STN CSC, Victoria, BC, V8W 2Y2, Canada. 3. Natural History Museum, University of Oslo, P.O. Box 1172 Blindern, NO-0318 Oslo, Norway Laboratory of Biosystematics and Cytology, Komarov Botanical Institute, Russian Academy of Sciences 197376 St. Petersburg, Russia. 4. Natural History Museum, University of Oslo, P.O. Box 1172 Blindern, NO-0318 Oslo, Norway. 5. Royal British Columbia Museum, 675 Belleville St., Victoria, BC, V8W 9W2, Canada. 6. Department of Biology, University of Victoria, PO Box 1700 STN CSC, Victoria, BC, V8W 2Y2, Canada Royal British Columbia Museum, 675 Belleville St., Victoria, BC, V8W 9W2, Canada School of Earth and Ocean Sciences, University of Victoria, PO Box 1700 STN CSC, Victoria, BC V8W 2Y2, Canada.
Abstract
PREMISE OF THE STUDY: Many arctic-alpine species have vast geographic ranges, but these may encompass substantial gaps whose origins are poorly understood. Here we address the phylogeographic history of Silene acaulis, a perennial cushion plant with a circumpolar distribution except for a large gap in Siberia. METHODS: We assessed genetic variation in a range-wide sample of 103 populations using plastid DNA (pDNA) sequences and AFLPs (amplified fragment length polymorphisms). We constructed a haplotype network and performed Bayesian phylogenetic analyses based on plastid sequences. We visualized AFLP patterns using principal coordinate analysis, identified genetic groups using the program structure, and estimated genetic diversity and rarity indices by geographic region. KEY RESULTS: The history of the main pDNA lineages was estimated to span several glaciations. AFLP data revealed a distinct division between Beringia/North America and Europe/East Greenland. These two regions shared only one of 17 pDNA haplotypes. Populations on opposite sides of the Siberian range gap (Ural Mountains and Chukotka) were genetically distinct and appear to have resulted from postglacial leading-edge colonizations. We inferred two refugia in North America (Beringia and the southern Rocky Mountains) and two in Europe (central-southern Europe and northern Europe/East Greenland). Patterns in the East Atlantic region suggested transoceanic long-distance dispersal events. CONCLUSIONS: Silene acaulis has a highly dynamic history characterized by vicariance, regional extinction, and recolonization, with persistence in at least four refugia. Long-distance dispersal explains patterns across the Atlantic Ocean, but we found no evidence of dispersal across the Siberian range gap.
PREMISE OF THE STUDY: Many arctic-alpine species have vast geographic ranges, but these may encompass substantial gaps whose origins are poorly understood. Here we address the phylogeographic history of Silene acaulis, a perennial cushion plant with a circumpolar distribution except for a large gap in Siberia. METHODS: We assessed genetic variation in a range-wide sample of 103 populations using plastid DNA (pDNA) sequences and AFLPs (amplified fragment length polymorphisms). We constructed a haplotype network and performed Bayesian phylogenetic analyses based on plastid sequences. We visualized AFLP patterns using principal coordinate analysis, identified genetic groups using the program structure, and estimated genetic diversity and rarity indices by geographic region. KEY RESULTS: The history of the main pDNA lineages was estimated to span several glaciations. AFLP data revealed a distinct division between Beringia/North America and Europe/East Greenland. These two regions shared only one of 17 pDNA haplotypes. Populations on opposite sides of the Siberian range gap (Ural Mountains and Chukotka) were genetically distinct and appear to have resulted from postglacial leading-edge colonizations. We inferred two refugia in North America (Beringia and the southern Rocky Mountains) and two in Europe (central-southern Europe and northern Europe/East Greenland). Patterns in the East Atlantic region suggested transoceanic long-distance dispersal events. CONCLUSIONS:Silene acaulis has a highly dynamic history characterized by vicariance, regional extinction, and recolonization, with persistence in at least four refugia. Long-distance dispersal explains patterns across the Atlantic Ocean, but we found no evidence of dispersal across the Siberian range gap.
Authors: Tigist Wondimu; Abel Gizaw; Felly M Tusiime; Catherine A Masao; Ahmed A Abdi; Yan Hou; Sileshi Nemomissa; Christian Brochmann Journal: PLoS One Date: 2017-05-26 Impact factor: 3.240
Authors: José Carlos Del Valle; Inés Casimiro-Soriguer; Mᵃ Luisa Buide; Eduardo Narbona; Justen B Whittall Journal: Front Plant Sci Date: 2019-11-15 Impact factor: 5.753