Burkhart JJ, Puckett EE, Beringer CJ, Sholy CN, Semlitsch RD, Eggert LS. Post-Pleistocene differentiation in a Central Interior Highlands endemic salamander.
Ecol Evol 2019;
9:11171-11184. [PMID:
31641463 PMCID:
PMC6802018 DOI:
10.1002/ece3.5619]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 07/30/2019] [Accepted: 08/07/2019] [Indexed: 11/07/2022] Open
Abstract
AIM
For many endemic species with limited dispersal capacities, the relationship between landscape changes and species distributions is still unclear. We characterized the population structure of the endemic ringed salamander (Ambystoma annulatum) across its distribution in the Central Interior Highlands (CIH) of North America, an area of high species endemism, to infer the ecological and evolutionary history of the species.
METHODS
We sampled 498 individuals across the species distribution and characterized the population genetic structure using nuclear microsatellite and mitochondrial DNA (mtDNA) markers.
RESULTS
Ambystoma annulatum exist in two strongly supported nuclear genetic clusters across the CIH that correspond to a northern cluster that includes the Missouri Ozark populations and a southern cluster that includes the Arkansas and Oklahoma Ozarks and the Ouachita Mountains. Our demographic models estimated that these populations diverged approximately 2,700 years ago. Pairwise estimates of genetic differentiation at microsatellite and mtDNA markers indicated limited contemporary gene flow and suggest that genetic differentiation was primarily influenced by changes in the post-Pleistocene landscape of the CIH.
MAIN CONCLUSIONS
Both the geologic history and post-European settlement history of the CIH have influenced the population genetic structure of A. annulatum. The low mtDNA diversity suggests a retraction into and expansion out of refugial areas in the south-central Ozarks, during temperature fluctuations of the Pleistocene and Holocene epochs. Similarly, the estimated divergence time for the two nuclear clusters corresponds to changes in the post-Pleistocene landscape. More recently, decreased A. annulatum gene flow may be a result of increased habitat fragmentation and alteration post-European settlement.
Collapse