Global warming lethal to baby lizards: Nests become heat traps

http://www.eurekalert.org/pub_releases/2015-08/asu-gwl081715.php

Public Release: 18-Aug-2015
Global warming lethal to baby lizards: Nests become heat traps
New study alters expected impact of climate change on lizards
Arizona State University

The expected impact of climate change on North American lizards is much worse than first thought. A team of biologists led by Arizona State University investigators has discovered that lizard embryos die when subjected to a temperature of 110 degrees Fahrenheit even for a few minutes.

The researchers also discovered a bias in previous studies, which ignored early life stages such as embryos. Embryonic lizards are immobile and cannot seek shade or cool off when their surrounding soil becomes hot.

This bias produced overly optimistic forecasts about the fate of lizards during climate change. Given the potential impacts on embryos, many more places in the United States could become uninhabitable for lizards than previously expected.

"Lizards put all of their eggs in one basket, so a single heat wave can kill an entire group of eggs," said Ofir Levy, lead investigator of the study and postdoctoral fellow with ASU School of Life Sciences. "If mothers don't dig deeper nests to lay their eggs, we expect this species to decline throughout the United States."

•••••