Dog Coats
Dogs diverged from a now-extinct Asian wolf between 12,000 and 15,000 years ago, according to recent DNA studies. In that time, the long nose and heavy grey-colored double coat of the wolf has changed into the wide variety of dog shapes and coats and colors seen today. The change was due at first to genetic changes that occurred as the original dogs learned to tolerate the presence of humans, as shown in the research on foxes by Dmitri Belyaev in his Farm-Fox Experiment. The research found that a genetic change to tameness brought along other unexpected changes as well; one notable change was in the coats, changed from a typical fox coat to a spotted coat resembling a dog's coat. As ancient dogs learned to live near humans and became less like wolves, their appearance changed as well, long before any selective breeding was done by people.
A Stanford University School of Medicine study published in Science in October, 2007 found the genetics that explain coat colors in other mammals such as in horse coats and in cat coats, did not apply to dogs. The project took samples from 38 different breeds to find the gene (a beta defensin gene) responsible for dog coat color. One version produces yellow dogs, and a mutation produces black. All dog coat colors are modifications of black or yellow. For example, the white in white miniature schnauzers is a cream color, not albinism (a genotype of e/e at MC1R.)
Today, dogs exhibit a diverse array of fur coats, including dogs without fur, such as the Mexican Hairless Dog. Dog coats vary in texture, color, and markings, and a specialized vocabulary has evolved to describe each characteristic.
Read more about this topic: Canine Terminology
Famous quotes containing the words dog and/or coats:
“All sailors pause to watch a steamer, and shout in welcome or derision. In one a large Newfoundland dog put his paws on the rail and stood up as high as any of them, and looked as wise. But the skipper, who did not wish to be seen no better employed than a dog, rapped him on the nose and sent him below. Such is human justice!”
—Henry David Thoreau (1817–1862)
“... [a] girl one day flared out and told the principal “the only mission opening before a girl in his school was to marry one of those candidates [for the ministry].” He said he didn’t know but it was. And when at last that same girl announced her desire and intention to go to college it was received with about the same incredulity and dismay as if a brass button on one of those candidate’s coats had propounded a new method for squaring the circle or trisecting the arc.”
—Anna Julia Cooper (1859–1964)