...put me onto this....

(emphasis mine)

Any thoughts?



LINEAGE DIVERSIFICATION IN A WIDESPREAD SPECIES: ROLES FOR NICHE DIVERGENCE AND CONSERVATISM IN THE COMMON KINGSNAKE, LAMPROPELTIS GETULA. R. Alexander Pyron and Frank T. Burbrink 2009. Molecular Ecology 18: 3443–3457. Abstract: Niche conservatism and niche divergence are both important ecological mechanisms associated with promoting allopatric speciation across geographical barriers. However, the potential for variable responses in widely distributed organisms has not been fully investigated. For allopatric sister lineages, three patterns for the interaction of ecological niche preference and geographical barriers are possible: (i) niche conservatism at a physical barrier; (ii) niche divergence at a physical barrier; and (iii) niche divergence in the absence of a physical barrier. We test for the presence of these patterns in atranscontinentally distributed snake species, the common kingsnake (Lampropeltisgetula), to determine the relative frequency of niche conservatism or divergence in asingle species complex inhabiting multiple distinct ecoregions. We infer the phylogeographic structure of the kingsnake using a range-wide data set sampled for themitochondrial gene cytochrome b. We use coalescent simulation methods to test for thepresence of structured lineage formation vs. fragmentation of a widespread ancestor.Finally, we use statistical techniques for creating and evaluating ecological niche modelsto test for conservatism of ecological niche preferences. Significant geographicalstructure is present in the kingsnake, for which coalescent tests indicate structuredpopulation division. Surprisingly, we find evidence for all three patterns of conservatismand divergence. This suggests that ecological niche preferences may be labile on recentphylogenetic timescales, and that lineage formation in widespread species can resultfrom an interaction between inertial tendencies of niche conservatism and naturalselection on populations in ecologically divergent habitats.



CNAH Note: In yet another elegant paper from the Burbrink laboratory, the authors divide the Common Kingsnake (Lampropeltis getula) into five species, as follows (text taken from the paper)



(from CNAH)Eastern: A lineage comprising the kingsnakes of the eastern seaboard of the United States, from New Jersey to the Florida Keys and extending to the Apalachicola region in the Florida panhandle and southeast Alabama (CNAH: will become Lampropeltis getula, the Eastern Kingsnake). Mississippi: This lineage ranges through the greater Mississippi River drainage east of the Mississippi River, from southern Illinois east to Ohio and western West Virginia in the north, to the Tennessee and Alabama river drainages of Georgia and Alabama in the south (CNAH: will become Lampropeltis nigra, the Black Kingsnake). Central: The Central lineage inhabits the Great Plains and Mississippi River valley west of the Mississippi River, from Iowa and Nebraska in the north to westcentral Texas and the western Gulf Slope in the south, east to the Mississippi River (CNAH: will become Lampropeltis holbrooki, the Speckled Kingsnake). Desert: The Desert lineage is found in the Chihuahan Desert of west Texas, southern New Mexico (including the Rio Grande River Valley), extreme southeastern Arizona and eastern Mexico, along the Mexican Plateau. May also occur in north central Arizona (CNAH: will become Lampropeltis splendida, the Desert Kingsnake). Western: The Western lineage occurs west of the Rocky Mountains, from the southern Great Basin in Nevada and Utah, southern Oregon south to Baja California, and most of Sonora, Mexico, east to southeastern Arizona (CNAH: will become Lampropeltis californiae, the California Kingsnake).



The following subspecies were not recognized as distinct: floridana, meansi, and nigrita.



The status of Lampropeltis catalinensis was not addressed.



:Mark
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Surrender Dorothy!



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