Fascinating article. Boston Globe Online / Health | Science / A mystery in black and white
Charles Darwin wrote: “Not a single domestic animal can be named which has not in some country drooping ears.” Not just dog breeds, but goat, llama, rabbit and even cat breeds sport flopped-over ears. Ears are just the start. The large black-and-white patches typical of dairy cows and pinto horses, not to mention dogs, cats, and rabbits, do not exist in their wild counterparts. And domestic animals characteristically have smaller heads, teeth, and horns, and go into heat more frequently.
What is remarkable about these differences is that they are so universal. The same traits are common to species as different as cats from cows, rabbits from dogs.
While the old explanation has been to say that people wanted these different traits and selectively bred for them (Who wouldn’t want a bull with shorter horns?), the global nature of the changes casts some doubt. To that, add this: No wild animals exhibit these traits. How would people even think to want pintos when there weren’t any spotted horses around in the first place?
Cited by Rand Simberg.
Last year I read The Goodness Paradox by someone named (i think) Wrangham. It says all these changes – lighter bones, shorter snout, white patches – follow from the delay of a single event in embryonic development. Domestication syndrome
The paradox of the title is that, among great apes, the hairless ones are most likely to kill in cold blood but least likely to kill in anger. The thesis is that our ancestors, around a quarter million years ago, domesticated themselves by conspiring to murder the most troublesome of their neighbors.