Sydney, July 28 - Mammals living in the tropics are evolving faster than those inhabiting cooler regions, according to a new study.

Previously, it had been assumed that rates of genetic change in warm-blooded animals were independent of climate.

The new study demonstrates that DNA evolution occurs substantially faster in mammal

species living in warmer environments, relative to those living in cooler environments.

The study was led by Auckland University of Technology (AUT) evolutionary biologist Len Gillman and colleagues.

Gillman says that over prolonged evolutionary periods, this difference in evolutionary rate might account for the enormous accumulation of biodiversity in warmer areas like the tropics.