|Art @vu06 (Potentially NSFW)
 The most domesticated animals. Domesticated animals become not only comfortable around people, but eventually start to stand and look like them too. May be the result of an ancient people or empire that domesticated animals a lot more thoroughly then normal villagers do now.
 Created by the Gods. Maybe they were created out of various animals to take the god's favorite attributes; the God of War creating people out of bloodthirsty wolves or bears, or the God of Plenty selecting cows and pigs as their mortal race avatars to represent them.
 They were once humans who wore animal skins to transform into them, or gain their powers at certain times. The suits were cursed, or the blood of these people mixed with the blood of the animals, turning them into half human creatures.
 Cursed by the Gods- animals or humans twisted into mockeries of both.
 Animal people are just really polite, well educated animals. Regular animals go around on all fours and eat gross, rotting food or each other because they just haven't been civilized. Leads to a more fairy tale style setting, where rabbits may have tea down in their burrows. Don't think about their lack of thumbs too much; donkeys stand up and swing swords around with awkward hoof-hands.
 Created in a arcane laboratory by an ancient progenitor race. Different animals were selected based on their usefulness- genetic super soldiers, laboring slaves, submissive house servants and so on. The original race was probably snake people or something, just to make it more confusing.
 Whenever a human breeds with an animal, this is the result. Kind of funny, kind of gross. Weird fantasy genetics- hopefully nobody tries to breed these with other half breeds, else you'll have some horrible chimera monsters.
 They're aliens from another planet or dimension. Them looking like animals in this world is just coincidence. It's convergent evolution.