Global warming may provoke evolution
mongabay.com
November 26, 2007




Some 80 million years ago, during a period of global warming, a group of relatively immobile salamanders trekked from western North America to the continent that became Asia, report researchers writing in this week's issue of the journal Proceedings of the National Academy of Science (PNAS).

The plethodontid salamanders are well known in herpetological circles for their bizarre geographical distribution: 98% of plethodontid species are found in North America, while the remainder live around the Mediterranean and in South Korea. The new study, based on DNA sequenced from three genes in 43 species of plethodontids, suggests a single colonization of Eurasia by plethodontids during the late Cretaceous.

Authors David R. Vieites, Mi-Sook Min, and David B. Wake speculate that future climate shifts could "provoke similar migration and change in modern animals in evolutionary timescales."

"Salamanders underwent rapid episodes of diversification and dispersal that coincided with major global warming events during the late Cretaceous and again during the Paleocene—Eocene thermal optimum," they write. "The major clades of plethodontids were established during these episodes, contemporaneously with similar phenomena in angiosperms, arthropods, birds, and mammals."

"Periods of global warming may have promoted diversification and both inter- and transcontinental dispersal in northern hemisphere salamanders by making available terrain that shortened dispersal routes and offered new opportunities for adaptive and vicariant evolution," the authors conclude.

CITATION: David R. Vieites, Mi-Sook Min, and David B. Wake (2007). Rapid diversification and dispersal during periods of global warming by plethodontid salamanders. PNAS November 27, 2007 vol. 104 no. 48

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CITATION:
mongabay.com (November 26, 2007).

Global warming may provoke evolution.

http://news.mongabay.com/2007/1126-salamanders.html