Monday, January 24, 2011

Did you ever wonderd why Dogs have Dew-Claws?

Dew claws are the remains of the first tå of the ancestors for the dogs. When members of the family dog began to specialize as runners during the evolution, their legs were longer and their feet fell from five to four toes. The first toes disappeared completely from hind legs of wild dogs, but the forelegs survived as remnants that are no longer touched the ground.
This design gives the Wolves an impressive turn of speed, 35 to 40 mph were recorded on several occasions over distances up to a quarter mile. Some limits of sixteen meters measured. Endurance over long distances is also remarkable. Huskies, the breed closest to the wolf ancestor, is known for a sledge over 500 miles to pull in a total time of only 80 hours. More specialized in running meant sacrifices in other directions.
The ability of dogs to climb and jump deteriorated as their continuous improvement. But their higher speed and greater endurance on the hunt was very effective and successful enough to the wild dogs to global survival, the warm tropics to the frozen wastelands.
So Dew-claws have to be on the way out, a casualty of the coming-of-age canines as athletes. But if so, then it seems strange to many breeds of dogs seem to be reversing. You would think that modern dogs, even farther away from the old dogs older than his wolves or dingoes would have lost all their dew claws, the 'thumbs' of the front foot in response to the big toe "of the hind legs oblivion.
Instead the opposite is true. Many modern breeds of dogs have dew claws all four present. The hind legs are never as solid or well fastened in front, usually consisting of no more than a free leg and a jaw loosely connected to the base with a small flap of skin, but they represent a small change in the dog's evolution. Breeds with dew claws back foot, however rudimentary, are closer in this respect than old dogs older than either the wolf or Dingo. Why this return to a primordial place?
The answer lies in what is called neoteny - persistently infantile characteristics in adult animals. This is what happened with the dogs during their 10,000 years of controlled breeding of humans. They really young wolves. They can breed, but they retain much of their early behaviors such as play and obedience to a pseudo-parent - the human owner. They also have a number of young anatomical features, such as floppy ears is seen in as many races today.
Conservation of extra dew claws are a part of this process. We have bred a series of increasingly extreme positions in the various modern breeds, but in other respects more primitive than the highly specialized wolf from which they were all distracted. In other words, when we do speak the wolf into the dog, we turned the clock back and forth.
It is interesting that growers feel intuitively that something is wrong with dew-claws and recommends that they be removed when the pups are 3-6 days old. They recognize it as a "trend unspecializing 'and correct. The stated excuse is that if they can remain rudimentary claws, they are entangled in bushes and torn. Given that the inside of their legs and above ground, this a rather improbable accident and a trivial excuse, but the unconscious urge to "refine" the dog's legs are strong enough to overlook it. (Except in some specific breeds, such as the Briard and the Pyrenees, where the hind dew claws must be kept to meet breed standards .)

1 comment:

  1. Although I am against docking of tails, ears etc. my dog did in fact rip out a dew claw climbing logs at the beach. He also just had an impacted dew claw cut at the vet. I wish I could have them removed but I believe its unethical to maim dogs for owners convenience. We need to get better at nail trims.

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