http://www.ultimateiditarod.com/faq.htm#The%20Dogs What kind of dogs are used in the Iditarod?
The most commonly used dog in the Iditarod (and in all of mushing) is the Alaskan Husky. The Alaskan Husky is actually a mixed breed, or mutt, dog that is born and bred to love to pull. Alaskan Huskies are a descendent of the original northern sled dogs (mostly domesticated wolves and wild dogs) used by the native peoples of the North Country...
Alaskan Malamutes are purebred derivatives of the original sled dogs, and can be considered cousins to the Alaskan Husky. Some mushers use these breeds, but these breeds lack the stamina, endurance, and attitude of the Alaskans.
http://www.pbs.org/wnet/nature/sleddogs/making.html In particular, husky breeders are looking for dogs with an instinctive desire to pull long and hard through the toughest conditions....
Still, careful breeding over decades has produced dogs with telltale physiques. For one thing, the best sled-pulling dogs have quick, efficient gaits and remarkable strength for their size. "You rarely see a really good sled dog over about 55 pounds,"
http://www.doggiefun.com/artman/publish/article_225.shtml Because of their adaptability to the cold, Alaskan climate, most sledding dogs are Alaskan Huskies.
http://www.answers.com/topic/iditarod The first major competition was the tremendously popular 1908 All-Alaska Sweepstakes (AAS), which was started by Allan "Scotty" Alexander Allan, and ran 408 miles (657 km) from Nome to Candle and back. The event introduced the first Siberian huskies to Alaska in 1910, where they quickly became the favored racing dog, replacing the Alaskan malamute, and mongrels bred from imported huskies and other large breeds, like setters and pointers.
I can go on and on.....
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