Sponsored Links








Add to Technorati Favorites

New Evolution Theory About Dogs

Thursday, December 30, 2004

An article published in Science News earlier this month suggests a different understanding of what drives in evolution in dogs.

It shows a photograph of three purebred bull terrier skulls from different periods, 1931, 1950, and 1976, which illustrates that their snouts have changed dramatically during this brief time period.

A scientist discovered that certain genes which shape a dog's final appearance can mistakes when replicating itself, causing rapid changes in the evolutionary process.

By comparing skulls of dogs over decades, Fondon and Garner found significant and swift changes in some breeds' appearances. For example, between the 1930s and today, purebred bull terriers developed longer, more down-turned noses.
The thing that I wonder about is if these scientists are certain that these bull terrier skulls really did come from purebred bull terriers.

1 Comments:

  • The changes in the Bull Terrier skulls most probably came from selection by breeders. If you look at photographs of purebred dog breeds over a period of 30-50 years, for example, many show dramatic differences in type due to selection by breeders for specific characteristics, such as head type. These differences are due to artificial selection by dog breeders, not natural selection. Natural selection would ultimately result in evolutionary changes. If dogs were left to breed randomly on their own, dog breeds as we know them would no longer exist. If the skulls did not come from purebred BT's, but from crosses with other bull breeds, there would be differences in skull types due to the genetic diversity between the different breeds. Artificial selection is not environmentally driven, as natural selection is, and does not result in new species; it does illustrate the genetic diversity present within a species. From a college biology professor who also breeds and shows purebred dogs.

    By Anonymous Anonymous, at 10:21 PM, December 30, 2004  

Post a Comment
Back to Homepage