Warming Pushing 30 Reptile & Amphibian Species To Higher Altitudes - If They Can Get There - MSNBC

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Global warming is forcing 30 species of reptiles and amphibians to move uphill as habitats shift upward, but they may soon run out of room to run. The shift could cause at least two toad species and one species of gecko in Madagascar to go extinct by the end of this century, a biologist says. Uphill movement is a predicted response to increased temperatures, researcher Christopher Raxworthy of the American Museum of Natural History says. Earlier studies in Costa Rica have provided evidence of how tropical animals respond to climate change.

The new research — based on surveys of Madagascar's amphibians and reptiles conducted in 1993 and 2003 and announced this week — extends that work, expanding the number and diversity of species that the trend affects, making a stronger link with meteorological changes, dealing with relatively large shifts in elevation, and assessing the extinction vulnerability for tropical communities in the mountains.

Nowhere to run

The animals that could go extinct are two species of narrow-mouth toads (Plethodontohyla tsarartananensis and Plethodontohyla sp. Z) and one species of gecko (Phelsuma l. punctulata) found in Madagascar’s mountainous north, Raxworthy said.

Two of these species were not found again during the most recent 2003 survey. (And for the 30 species that were re-sampled between 1993 and 2003, the majority are already moving upslope to compensate for habitat loss at lower and warmer altitudes.) Extinction is expected to occur between 2050 and 2100 if current trends persist, because there will eventually be no higher ground, predict Raxworthy and his colleagues from the Université d’Antananarivo in Madagascar, National Chung-Hsing University in Taiwan, University of Michigan and University of Oxford. The prediction is based on a conservative scenario in which warming remains below 2 degrees C (3 degrees F). Warming above 2 degrees C is considered to be dangerous in terms of impacts on biodiversity.

EDIT

http://www.msnbc.msn.com/id/25125495/

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1. Wow. Failure of percolating fitness landscapes analogy comes to life.

There's an analogy used to illustrate nonpercolating fitness landscapes, where a poison gas accumulates in the valleys of a mountain range, and as the gas rises, there are fewer and fewer pathways between the peaks of the mountains. Eventually, all the peaks become islands, and that is the point where there are no longer any adaptation pathways. The environment has changed faster than evolution can keep up.

Replace poison gas with temperature, and this is the living embodiment of that analogy.

:wow:

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2. Interesting - kind of the Lake Nios model for forced migration

Damn.

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3. Yikes, I hadn't thought of that incident.

Much more local, but a lot faster.