Quaternary climate fluctuations restructured biodiversity across North American high latitudes through repeated episodes of range contraction, population isolation and divergence, and subsequent expansion. Identifying how species responded to changing environmental conditions not only allows us to explore the mode and tempo of evolution in northern taxa, but also provides a basis for forecasting future biotic response across the highly variable topography of western North America. Using a multilocus approach under a Bayesian coalescent framework, we investigated the phylogeography of a wide‐ranging mammal, the long‐tailed vole,
Divergence is often ephemeral, and populations that diverge in response to regional topographic and climatic factors may not remain reproductively isolated when they come into secondary contact. We investigated the geographical structure and evolutionary history of population divergence within
- Award ID(s):
- 2023723
- NSF-PAR ID:
- 10446483
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Molecular Ecology
- Volume:
- 31
- Issue:
- 2
- ISSN:
- 0962-1083
- Page Range / eLocation ID:
- p. 620-631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Aim Refugial isolation during glaciation is an established driver of speciation; however, the opposing role of interglacial population expansion, secondary contact, and gene flow on the diversification process remains less understood. The consequences of glacial cycling on diversity are complex and especially so for archipelago species, which experience dramatic fluctuations in connectivity in response to both lower sea levels during glacial events and increased fragmentation during glacial recession. We test whether extended refugial isolation has led to the divergence of genetically and morphologically distinct species within Holarctic ermine (
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Methods We use genetic sequences (complete mitochondrial genomes, four nuclear genes) from >100 ermine (stoats) and geometric morphometric data for >200 individuals (27 of the 34 extant subspecies) from across their Holarctic range to provide an integrative perspective on diversification and endemism across this complex landscape. Multiple species delimitation methods (
iBPP ,bPTP ) assessed congruence between morphometric and genetic data.Results Our results support the recognition of at least three species within the
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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Abstract Aim The “sexy shrimp”
Thor amboinensis is currently considered a single circumtropical species. However, the tropical oceans are partitioned by hard and soft barriers to dispersal, providing ample opportunity for allopatric speciation. Herein, we test the null hypothesis thatT. amboinensis is a single global species, reconstruct its global biogeographical history, and comment on population‐level patterns throughout the Tropical Western Atlantic.Location Coral reefs in all tropical oceans.
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Abstract Chromosomal rearrangement can be an important mechanism driving population differentiation and incipient speciation. In the mountain pine beetle (
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