Do you know about that widely praised book, "The world without humans" or something like that? In it, cats are said to be the only pet species that would survive in the long run, because their instincts -if you want to call it that- are still intact enough. All others would go extinct, with rare exceptions, when the predators of the animal world returned. I don't know wether to divide between human emotions and an animal's or not. I think it is artificial, but I still wouldn't deem animal as respnsible for their "cruel" actions as a human being.