Donald Miles, Ph.D.
- Professor of Biological Sciences
Areas of Expertise
- Amphibians
- Birds
- Climate Change
- Drought Stress
- Evolutionary Morphology
- Global Warming
- Life History Variation
- Lizard Population and Extinction
- Lizards
Expert Bio
In 2010, Dr. Miles and colleagues released the results of an alarming study - lizard populations are quickly becoming extinct around the world.
Miles - who has devoted years of study to lizards - determined rising temperatures are to blame. The climate is changing faster than lizards can adapt. If global warming patterns continue, Miles and fellow researchers estimate over 20 percent of all lizard species may become extinct by 2080 in areas on the continents of North and South America, Europe, Africa and Australia.
In several locations the team found lizard populations they had previously studied had already become extinct. Madagascar has already lost 21 percent of the local lizard population, including such species as chameleons and gekkos, Miles says.
In order to prove their theory of climate change, the scientists chose to focus on populations with no habitat loss, many in protected, undisturbed environments where temperature is the only changing factor.
To investigate the link between these extinctions and temperature, the team of French, Mexican and American researchers built a device that mimics the body temperature of a lizard basking in the sun and records the temperatures on a microchip.
Lizards bask in the sun to increase their core body temperature and forage for food. But Miles and his team discovered that if temperatures became too hot, the lizards retreated into shaded areas, forcing them to abandon the hunt for food. In some locations, the team discovered the temperatures had grown too rapidly and the lizards had barely emerged before having to retreat to cooler spots. Extinction in these areas had already begun as a result. The disappearance of lizards may directly impact other species, such as birds or snakes, who feed on the reptiles.
An organismal biologist, Miles also conducts natural selection research at sites in Arizona's Sonoran Desert and central New Mexico. He studies characteristics, such as speed and strength and their relation to survival and reproduction.
Miles has also devoted years of research to the study of birds - most recently the effects of controlled forest burning on nesting success.