According to Evolution, dogs descended from a genet-like tree-climbing carnivore some 40million years ago, and began to differentiate into wolves, foxes, coyotes, fennecs and jackals about 7million years ago. Initially they would have been grouped with carnivores including bears and raccoons, however their evolution is now considered to be more closely linked to that of cats. When dogs began to follow nomadic groups, eating the humans leftovers, domestication began to occur. This was originally thought to have occurred around 10,000 years ago, although recent fossil records show that this could have happened much earlier. At this point the selective breading into the various canine breeds began to develop, resulting in over 400 separate breeds.