We have domesticated dogs, and they come in very different shapes and sizes, but all the domestic cats are (roughly) the same size and almost all look alike (at least, their differences are much less noticeable than between dogs races). Evidently, there ARE felines that are much, much bigger than cats, but I've never seen a domestic cat that size... Is there a reason besides the fact that they're dangerous? after all, an alaskan malamute could kill you in a heartbeat, but they choose not to, couldn't the same apply to big domesticated cats?
EDIT: Wow, frontpage! =...) thanks AskScience for a very interesting discussion! now, back to study, I have a test in a couple hours (it's grad school, God forbid you people think I'm a teenager and start a downvote festival)