Jun
29
2009

Warmer climate accelerates evolution in mammals

Warmer climate boosts evolution: Okay, so iguanas aren't mammals, and I doubt Charles Darwin ever visited Sloppy Joe's in Key West, Florida, but the graphic still illustrates the point.
Warmer climate boosts evolution: Okay, so iguanas aren't mammals, and I doubt Charles Darwin ever visited Sloppy Joe's in Key West, Florida, but the graphic still illustrates the point.Courtesy Apollo13Ma (background photo), public domain and Mark Ryan
A study out of New Zealand says a warmer climate speeds up molecular evolution in mammals. The concept isn’t exactly a new one. Scientists have known that a warmer environment increases the pace of microevolution for other types of life, such as some plants and marine animals, but evidence that it affects mammals – which are warm-blooded (meaning their temperature is regulated internally) – has not been observed before.

Lead researcher, Len Gillman from Auckland University of Technology, said the result of the study was “unexpected”.

""We have previously found a similar result for plant species and other groups have seen it in marine animals. But since these are 'ectotherms' - their body temperature is controlled directly by the environment - everyone assumed that the effect was caused by climate altering their metabolic rate.""

Since DNA can potentially mutate each time a cell divides into two copies of itself, the faster (and more often) these divisions take place, the more chances advantageous mutations will be passed onto subsequent generations, and the faster microevolution takes place.

Gillman and his crew traced and compared small genetic changes in 130 pairs of related species that lived in different latitudes, focusing on a single gene in each pair. They then compared the gene against that of a common ancestor, and were able to determine which of the two mammals’ DNA had mutated (microevolved) more rapidly. The changes were small-scale, but the species living in the more tropical environment showed a faster pace in its level of molecular evolution.

The results of the study appear in Proceedings of the Royal Society B.

LINKS
Discover magazine story
BBC story
More about evolution

Post new comment

The content of this field is kept private and will not be shown publicly.
  • Allowed HTML tags: <a> <h3> <h4> <em> <i> <strong> <b> <span> <ul> <ol> <li> <blockquote> <object> <embed> <param> <sub> <sup>
  • Lines and paragraphs break automatically.
  • You may embed videos from the following providers vimeo, youtube. Just add the video URL to your textarea in the place where you would like the video to appear, i.e. http://www.youtube.com/watch?v=pw0jmvdh.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Images can be added to this post.

More information about formatting options