Mammals Evolve Faster in the Tropics

(June 25) - Mammals living in the tropics are experiencing genetic mutations more quickly and therefore are evolving faster than those in cooler environments, according to a New Zealand study.

The study, conducted by researchers at the Auckland University of Technology, counters a longstanding assumption that climate does not impact the genetic mutations of warm-blooded animals, the Australian Associated Press reported.

"The results show that species occupying warmer climates have almost 50 percent more DNA evolution relative to those in cooler climates," biologist Len Gillman told the news service. "These results come from pairs of species generally living in close proximity to each other so we would expect the effect to be far more pronounced over continental and global scales."

Prior studies have shown that plants and certain marine life evolve faster in warmer climates. But the New Zealand study is first evidence of microevolution in mammals, the BBC News reported. Microevolution occurs when a population changes genetically over time in a way that is advantageous for the animal, such as developing a resistance to disease or pesticides. The gene is then passed down to future generations.

"The result was unexpected," Gillman told the BBC of the study, which looked at 260 mammal species.

The findings were published on Thursday in the biological research journal Proceedings B.