Proof Of Evolution Shows Up In Wolves?

Researchers investigate the genetic secrets of North American black coated wolves and come up with some interesting conclusions.

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The blackness comes from a genetic mutation of the gene that controls melanism. After discovering that this gene is responsible for melanism in dogs and also in the wild coyotes and wolves Dr. Gregory S. Barsh of Standford University and the researchers set out to discover where and when the mutation evolved.

This is where the really "interesting" discoveries begin. Mark Derr of the New York Times reports that Dr. Barsh and his colleagues concluded that the mutation arose in dogs 12,779 to 121,182 years ago [give or take 100 000 years]. Although they preferred a date of 46,886 years ago. This would be because the first domesticated dogs are estimated to date back just 15,000 to 40,000 years ago.

The researchers said, according to the same article, "that they could not determine with certainty whether the mutation arose first in wolves that pre-date that time, or in dogs at an early date in their domestication." They seem to have ruled out the possibility of it occurring in a common ancestor of the two. In fact, Dr. Robert K. Wayne, co-author and evolutionary biologist, unbiasedly believes "the mutation occurred first in dogs. But even if it arose first in wolves, he said, it was passed on to dogs who brought it to the New World and then passed it to wolves and coyotes soon after their arrival."

I think the science of their discoveries is seriously tainted by what they hoped to find. Randolph E. Schmid writing for the Associated Press quotes Yale University researcher Mark Gerstein;

"Positive selection is an important driving force in mammalian evolution. However, there are not many concrete and dramatic examples of it in action. This paper demonstrates such an example using coat color in wolves — an easy to recognize and relate to characteristic."

He went on to praise the researchers for their efforts in "developing a clear, evolutionary history of the genes that determine color in wolves." Which, given the credentials the of researchers, sounds like the a priori that they started with.

The claim that continued existence of the mutation supports positive selection remains unsupported as Barsh admits it is unlikely the dark color has any camouflage advantages to a predator close to the top of the food chain for protection, nor in its ability to hunt its prey. They found the genetic protein controlling the color in wolves is associated with fighting inflammation and infection in humans which he believes might be beneficial to the wolves in woodland areas where the dark color is most prominent.

I am all for scientific research, but if these reports are to be given any credulity the "scientists" need to refrain from diluting the facts to the point of pseudo science with their beliefs, estimates and preferences.

References:

http://www.google.com/hostednews/ap/article/ALeqM5iZjsnV-L-O_aC9TXdjW3OIAJJFIwD965JGP00

http://www.nytimes.com/2009/02/06/health/06wolves.html?_r=1

http://www.sciencemag.org/cgi/content/abstract/1165448v1

Tags: Dog Wolf Genes Dark Wolves Evolution Proof Of Evolution First Domesti

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