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Friday, September 04, 2009

New at ARN: Dear mice: We are pleased to inform you that you are now an icon of evolution

From British physicist David Tyler, on how deer mice became the most recent icons of "evolution in action" due to coat colour variations:

What this research does not do is lend support to Charles Darwin's claim that evolution by natural selection is the key to understanding the development of biological complexity and the origin of species. the genetic changes associated with the modified coat colour are attributed to the deletion of a single amino acid in the Agouti gene - there is no increase in information and no move towards specified complexity. It is necessary to point this out because some (e.g. the BBC report) are suggesting this research is so important for evolutionary theory that it deserves iconic status.
Icon? Hard to believe, but true. Basically, losing a gene doesn't get us very far in understanding the evolution of complex life forms. What we want to know is how to gain a gene.

Anyway, I wonder whether coat colour changes lead to the formation of new species very often, in the sense that the life forms can no longer interbreed. Coat changes must usually follow local environment changes that favour one colour over another.
Animals with white winter coats may do well in a snow belt, but are highly visible otherwise. That is an example of natural selection, of course. But these changes may be short term, considering geological time, and the genes to migrate back when the environment changes may still exist. If so, it is probably a good thing because too much incidental speciation would threaten extinction any time the local environment changed.

Find out why there is an intelligent design controversy:


Coffee! Evolution in action? Or do wolves and coyotes just desperately need sex ed?

The one on the left is a coyote and the one on the right is a wolf. Hybrids can be anywhere in between.
Does anyone remember when “speciation” meant something? Here’s an item from the Toronto news: "Meet the coywolf: A newly emerging species is behind the brazen attacks in Durham":
The predators that are plaguing Durham Region and showing up in urban areas appear to be an emerging species resulting from wolves and coyotes interbreeding.

The larger, highly adaptable animals "have the wolf characteristics of pack hunting and aggression and the coyote characteristics of lack of fear of human-developed areas," says Trent University geneticist Bradley White, who's been studying the hybrids for 12 years.

We're seeing "evolution in action," he says.

But that combination of genetic material from both species has spelled trouble for farmers, who are losing a growing number of livestock to predators. (August 15, 2009)
Star writer Carola Vyhnak, urban affairs reporter, was informed that this is an example of a new species forming, in other words, "evolution in action." Not so in this case. This is a hybrid.

Wolves and coyotes have always had the ability to interbreed, producing a coywolf. They usually won't if they have the choice of their own kind. But wolf elimination programs probably force the remaining wolves to hit on coyotes. Among canines generally, the rule seems to be "If yer not with the one ya love, ya love the one yer with! Yap! Yap! Yap!

Maybe sex ed would teach them to look for the right mates. But the program has been stalled because farmers are demanding that they be given abstinence education instead, pronto.

Incidentally, there are also coydogs and wolfdogs.

Note: These animals do not make good pets. They were born wild and they like it. People who want a pet should adopt a friendly shelter dog who really wants to live with people.

A link with great photos of wild canines around the world.


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