Reply To: Global warming threatens biodiversity


From Washington Post:

an international team of biologists reports that in more than one-tenth of the places in Mexico where lizards flourished in 1975, the reptiles now cannot be found. The researchers predict that by 2080, about 40 percent of local lizard populations worldwide will have died off and 20 percent of lizard species will be extinct.

The reason for the huge die-off appears to be rising temperatures. But it isn't heat that is killing the lizards directly.

Instead, global warming appears to be lengthening the period of the day when lizards must seek shelter or risk fatal overheating. In the breeding season, that sheltering period is now so long that females of many species are unable to eat enough food to produce eggs and offspring.

Springs that start earlier and are warmer than they once were have been noted in many regions of the world in the past three decades. The new study suggests that the phenomenon may be far more important for the survival of some animals than peak summer temperatures, said Barry Sinervo, an evolutionary biologist at the University of California at Santa Cruz who headed the 26-person research team.

"It is as if something has really happened in world climate and the lizards are telling us that," he said.

The lizard findings also suggest that early stages of global warming may be more than a warning: They may have permanent consequences.

"Many of us have been worried about extinctions in the future," said Raymond B. Huey, a lizard physiologist at the University of Washington in Seattle, who wrote a commentary accompanying the study. "This paper shows that extinctions are already here. I think that will really be surprising to most biologists."

Global warming blamed for pattern of lizard deaths