Re: "before humans farmed animals"
"So you're suggesting that before humans farmed animals, the said animals (e.g. cows) did not exist"
Well, actually yes. Modern farm animals did not exist before humans farmed them. We MADE cows, by selectively breeding the meatiest and most docile wild aurochs over many generations. Much the same occurred with chickens from jungle fowl, pigs from wild boars, dogs from wolves, etc.