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Global warming may provoke evolution mongabay.com November 26, 2007
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 Related articles Mass extinctions happen when temperatures are the warmest (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.
(3/26/2007) Many of the world's local climates could be radically changed if global warming trends continue, reports a new study published in the early online edition of the journal Proceedings of the National Academy of Sciences. The authors warn that current climates may shift and disappear, increasing the risk of biodiversity extinction and other ecological changes.
(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 (3/21/2007) 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.
(3/12/2007) While there is considerable debate over the scale at which biodiversity extinction is occurring, there is little doubt we are presently in an age where species loss is well above the established biological norm. Extinction has certainly occurred in the past, and in fact, it is the fate of all species, but today the rate appears to be at least 100 times the background rate of one species per million per year and may be headed towards a magnitude thousands of times greater. Few people know more about extinction than Dr. Peter Raven, director of the Missouri Botanical Garden. He is the author of hundreds of scientific papers and books, and has an encyclopedic list of achievements and accolades from a lifetime of biological research. These make him one of the world's preeminent biodiversity experts. He is also extremely worried about the present biodiversity crisis, one that has been termed the sixth great extinction. Extinction risk accelerated when interacting human threats interact (2/7/2007) A new study warns that the simultaneous effect of habitat fragmentation, overexploitation, and climate warming could increase the risk of a species' extinction. News index | RSS | Add to MyYahoo! Advertisements: Organic Apparel from Patagonia | Insect-repelling clothing |
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