Pleistocene glacial refugia across the Appalachian Mountains and coastal plain in the millipede genus Narceus: Evidence from population genetic phylogeographic and paleoclimatic data

ECU Author/Contributor (non-ECU co-authors, if there are any, appear on document)

Jason E. Bond (Creator)

Paul E. Marek (Creator)

Amy K. Stockman (Creator)

Matt J. Walker (Creator)

Institution

East Carolina University (ECU )

Web Site: http://www.ecu.edu/lib/

Abstract: Background: Species that are widespread throughout historically glaciated and currently nonglaciated areas provide excellent opportunities to investigate the role of Pleistocene climatic change on the distribution of North American biodiversity. Many studies indicate that northern animal populations exhibit low levels of genetic diversity over geographically widespread areas whereas southern populations exhibit relatively high levels. Recently paleoclimatic data have been combined with niche-based distribution modeling to locate possible refugia during the Last Glacial Maximum. Using phylogeographic population and paleoclimatic data we show that the distribution and mitochondrial data for the millipede genus Narceus are consistent with classical examples of Pleistocene refugia and subsequent post-glacial population expansion seen in other organismal groups. Results: The phylogeographic structure of Narceus reveals a complex evolutionary history with signatures of multiple refugia in southeastern North America followed by two major northern expansions. Evidence for refugial populations were found in the southern Appalachian Mountains and in the coastal plain. The northern expansions appear to have radiated from two separate refugia one from the Gulf Coastal Plain area and the other from the mid-Atlantic coastal region. Distributional models of Narceus during the Last Glacial Maximum show a dramatic reduction from the current distribution with suitable ecological zones concentrated along the Gulf and Atlantic coastal plain. We found a strong correlation between these zones of ecological suitability inferred from our paleo-model with levels of genetic diversity derived from phylogenetic and population estimates of genetic structuring. Conclusion: The signature of climatic change during and after the Pleistocene on the distribution of the millipede genus Narceus is evident in the genetic data presented. Niche-based historical distribution modeling strengthens the conclusions drawn from the genetic data and proves useful in identifying probable refugia. Such interdisciplinary biogeographic studies provide a comprehensive approach to understanding these processes that generate and maintain biodiversity as well as the framework necessary to explore questions regarding evolutionary diversification of taxa. Originally published BMC Evolutionary Biology Vol. 9 No. 25 Jan 2009

Additional Information

Publication

Other

BMC Evolutionary Biology. 9:25(January 2009) p. 1-11.

Language: English

Date: 2011

Keywords

post-glacial population expansion, Pleistocene refugia, genetic diversity

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