Musk Ox
Musk ox are more closely related to goats than to cows or buffalo. They can look very scary with their wide horns. Like other arctic animals the musk ox has a double coat to keep warm. It's inner coat is made of some of the finest wool known and is collected and spun into yarn. A sweater made of musk ox wool costs over one thousand dollars.
Special fact: Musk ox challenge each other by ramming into each other head first. After more than one dozen times one of the challengers will have enough and back down.