A new study published at Science Daily details how researchers collected data on 50 different skull points of domesticated dogs. They found that there was more of a range of skull sizes and shapes among domesticated dogs than there were between two totally different species, like the cat and the walrus.
“We usually think of evolution as a slow and gradual process,” said study researcher Abby Drake of the of the College of the Holy Cross in Massachusetts. “But the incredible amount of diversity in domestic dogs has originated through selective breeding in just the last few hundred years, and particularly after the modern purebred dog breeds were established in the last 150 years.”
Usually nature does the work of changing the shape and look of mammals, but not so with domesticated dogs.
“Dogs are bred for their looks not for doing a job, so there is more scope for outlandish variations, which are then able to survive and reproduce,” said study researcher Chris Klingenberg, a biologist at the University of Manchester. “Natural selection has been relaxed and replaced with artificial selection for various shapes that breeders favor.”
The study was originally reported in the January 20,2010 edition of “The American Naturalist.”