Global warming may provoke evolution
Global warming may provoke evolution
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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(10/24/2007) Warming temperatures could trigger a mass extinction event, warn scientists writing in the latest issue of Proceedings of the Royal Society B. Comparing ancient records of marine and terrestrial diversity with historical temperature estimates, researchers from the Universities of York and Leeds found a close correlation between Earth climate and extinctions over the past 520 million years: higher extinction rates occur at higher temperatures.
Climate change will cause biomes to shift and disappear
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Extinction, like climate change, is complicated
(3/26/2007) Extinction is a hotly debated, but poorly understood topic in science. The same goes for climate change. When scientists try to forecast the impact of global change on future biodiversity levels, the results are contentious, to say the least. While some argue that species have managed to survive worse climate change in the past and that current threats to biodiversity are overstated, many biologists say the impacts of climate change and resulting shifts in rainfall, temperature, sea levels, ecosystem composition, and food availability will have significant effects on global species richness.
Global warming may cause biodiversity extinction
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Extinction risk accelerated when interacting human threats interact
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