Basically, they were domesticated because of a mutual need. In ancient Egypt,, the stored grain attracted mice. When it was discovered that cats killed the mice and saved the grain, the cats became the favorites of the Egyptians and were revered as gods. Wolves, the ancestors of dogs, found it easier to steal food from people than to hunt. They began to lose their fear of man and were able to be tamed and used to aid hunters in their quest for meat. Selective breeding created today's helpers and companions.