New research from the American Museum of Natural History provides the first detailed study showing that global warming forces species to move up tropical mountains as their habitats shift upward. Christopher Raxworthy, Associate Curator in the Department of Herpetology, predicts that at least three species of amphibians and reptiles found in Madagascar's mountainous north could go extinct between 2050 and 2100 because of habitat loss associated with rising global temperatures. These species, currently moving upslope to compensate for habitat loss at lower and warmer altitudes, will eventually have no place to move to.
"Two things togetherhighly localized distribution close to the very highest summits, and the magnitude of these upslope shifts in response to ongoing warmingmake a poisonous cocktail for extinction," said Raxworthy. In a paper published this month in Global Change Biology, Raxworthy and colleagues found overall trends for elevation changes among 30 species of amphibians and reptiles. Uphill movement is a predicted response to increased temperatures, and other studies, including that of J. Alan Pounds in Costa Rica, have provided some empirical evidence of how tropical animals respond to climate change. Raxworthy's research, however, is distinguished by the number and diversity of species, the demonstrated meteorological changes over the same time period, the relatively large shifts in elevation, and the broader assessment of extinction vulnerability for tropical montane communities. Currently, there is also a dearth of information available concerning climate impacts on biodiversity for tropical regions.
Raxworthy has been surveying the diversity of Madagascar's herpetological assemblage since 1985 and discovered the uphill migration almost by chance while in the field. On repeated surveys of northern Madagascar's mountains, the Tsaratanana Massif, he noticed that some species were missing from camps where they'd been pre
|Contact: Kristin Phillips|
American Museum of Natural History