The integration of ecological niche modelling into phylogeographic analyses has allowed for the identification and testing of potential refugia under a hypothesis‐based framework, where the expected patterns of higher genetic diversity in refugial populations and evidence of range expansion of nonrefugial populations are corroborated with empirical data. In this study, we focus on a montane‐restricted cryophilic harvestman,
The Hengduan Mountains region is a biodiversity hotspot known for its topologically complex, deep valleys and high mountains. While landscape and glacial refugia have been evoked to explain patterns of interspecies divergence, the accumulation of intra‐species (i.e., population level) genetic divergence across the mountain‐valley landscape in this region has received less attention. We used genome‐wide restriction site‐associated DNA sequencing (RADseq) to reveal signatures of Pleistocene glaciation in populations of
- NSF-PAR ID:
- 10415050
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Molecular Ecology
- Volume:
- 32
- Issue:
- 11
- ISSN:
- 0962-1083
- Page Range / eLocation ID:
- p. 2695-2714
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Mustela erminea ), a small cosmopolitan carnivore species that harbours 34 extant subspecies, 14 of which are insular endemics.Location Holarctic.
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M. erminea complex, coincident with three of four genetic clades, tied to diversification in separate glacial refugia. We found substantial geographic variation within each species, with geometric morphometric results largely consistent with historical infraspecific taxonomy.Main conclusions Phylogeographic structure mirrors patterns of diversification in other Holarctic species, with a major Nearctic‐Palearctic split, but with greater intraspecific morphological diversity. Recognition of insular endemic species
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LGM ), many plant and animal taxa have expanded their ranges by migration from glacial refugia. Weeds of cultivation may have followed this trend or spread globally following the expansion of agriculture or ruderal habitats associated with human‐mediated disturbance. We tested whether the range expansion of the weedSilene vulgaris across Europe fit the classical model of postglacial expansion from southern refugia, or followed known routes of the expansion of human agricultural practices. We used species distribution modeling to predict spatial patterns of postglacial expansion and contrasted these with the patterns of human agricultural expansion. A population genetic analysis using microsatellite loci was then used to test which scenario was better supported by spatial patterns of genetic diversity and structure. Genetic diversity was highest in southern Europe and declined with increasing latitude. Locations of ancestral demes from genetic cluster analysis were consistent with areas of predicted refugia. Species distribution models showed the most suitable habitat in theLGM on the southern coasts of Europe. These results support the typical postglacial northward colonization from southern refugia while refuting the east‐to‐west agricultural spread as the main mode of expansion forS. vulgaris . We know thatS. vulgaris has recently colonized many regions (including North America and other continents) through human‐mediated dispersal, but there is no evidence for a direct link between the Neolithic expansion of agriculture and current patterns of genetic diversity ofS. vulgaris in Europe. Therefore, the history of range expansion ofS. vulgaris likely began with postglacial expansion after theLGM , followed by more recent global dispersal by humans.
