Dogs are descended from wolves. Wolves live in hierarchical packs in which the aggressive alpha male rules over everyone else. Therefore, humans need to dominate their pet dogs to get them to behave.

This logic has dominated the canine-rearing conversation for more than five years, thanks mostly to National Geographic's award-winning show, Dog Whisperer with Cesar Millan.

But many experts say Millan's philosophy is based on now-debunked animal studies and that some of his techniques — most famously the alpha roll, in which he pins a dog on its back and holds it by the throat — are downright cruel.