What animal species do you believe are relative newcomers? I'm assuming here that you mean species that have come into being since humans stopped being hunter

What animal species do you believe are relative newcomers? I'm assuming here that you mean species that have come into being since humans stopped being hunter gatherers -- let's say 10k ya. For me, natural means what they evolved to consume. So for cattle, and their genetic ancestors, it'd be grass, with perhaps some shrubby plants and trees. It certainly wasn't grains, for obvious reasons.