Dataset Information

Complex cycles of divergence and migration shape lineage structure in the common kingsnake species complex.

ABSTRACT:

Aim

The Nearctic is a complex patchwork of habitats and geologic features that form barriers to gene flow resulting in phylogeographic structure and speciation in many lineages. Habitats are rarely stable over geologic time, and the Nearctic has undergone major climatic changes in the past few million years. We use the common kingsnake species complex to study how climate, geography, and history influence lineage formation over a large, complex landscape.

Location

Nearctic/North America.

Taxon

Common kingsnake, Lampropeltis getula, species complex.

Methods

We analyzed genome-wide sequence data from 51 snakes spanning the majority of the species complex's range. We used population clustering, generalized dissimilarity modeling, and coalescent methods to identify the number of genetic clusters within the L. getula complex, infer the environmental correlates of genetic differentiation, and estimate models of divergence and gene flow among lineages.

Results

We identified three major lineages within the L. getula complex and further continuous spatial structure within lineages. The most important ecological correlates of genetic distance in the complex are related to aridity and precipitation, consistent with lineage breaks at the Great Plains/Desert ecotone and the Cochise Filter Barrier. Lineages are estimated to have undergone multiple rounds of isolation and secondary contact, with highly asymmetric migration occurring at present.

Main conclusions

Changing climates combined with a large and geologically complex landscape have resulted in a mosaic of discrete and spatially continuous genetic structure. Multiple rounds of isolation and secondary contact as climate fluctuated over the past ~4.4 My have likely driven the evolution of discrete lineages that maintain high levels of gene flow. Continuous structure is strongly shaped by aridity and precipitation, suggesting roles for major precipitation gradients in helping to maintain lineage identity in the face of gene flow when lineages are in geographic contact.

SUBMITTER: Harrington S

PROVIDER: S-EPMC9937589 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Complex cycles of divergence and migration shape lineage structure in the common kingsnake species complex.

Harrington Sean S Burbrink Frank F

Journal of Biogeography. 20221123 2

<h4>Aim</h4>The Nearctic is a complex patchwork of habitats and geologic features that form barriers to gene flow resulting in phylogeographic structure and speciation in many lineages. Habitats are rarely stable over geologic time, and the Nearctic has undergone major climatic changes in the past few million years. We use the common kingsnake species complex to study how climate, geography, and history influence lineage formation over a large, complex landscape.<h4>Location</h4>Nearctic/North A ...[more]

PMID: 36817740

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Dataset Information

Complex cycles of divergence and migration shape lineage structure in the common kingsnake species complex.

Aim

Location

Taxon

Methods

Results

Main conclusions

Publications

Complex cycles of divergence and migration shape lineage structure in the common kingsnake species complex.

Similar Datasets

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