Not many animals have been domesticated throughout history. Only a few large mammals (16) can be easily domesticated. The first domesticated animals were probably dogs. They were used first as help for hunting. Then, later, animals were used for agriculture. The first agricultural animals were probably domesticated for meat. But then, other resources such as eggs, milk, wool, muscles and transportation became bonuses. Cows, goats, reindeer, yaks, llamas and sheep provided milk. Sheep and llamas provided wool. Chickens provided eggs. Camels, horses, donkeys and elephants provided transportation. Water buffalos, oxen, horses, donkeys, llamas, elephants and camels made good pack animals. Other animals have been trained for help with vermin. Cats and ferrets caught mice. In the time of the pilgrims, pigs were trained to kill rattlesnakes. Other animals were trained for hunting. Dogs were trained by cavemen to hunt. Cheetahs were trained by Ancient Assyrian peoples to hunt. In the middle ages (and still today), falcons and hawks were trained to hunt small things like rabbits. Ferrets were also trained in the middle ages to hunt rabbits. Ancient Chinese fisherman trained cormorants to catch fish from rivers or the ocean for the fisherman. This tradition continues today. Some animals, such as elephants or horses, used for riding purposes, could also be used for battle.