Unfortunately, this statement about animals getting on together is false, generally most species are aggressive! Birds will have fights over territory, cats scrap all the time, even peace loving creatures like dolphins will fight to prove who is alpha-male in courtship! \n\nMankind is just a more elaborate form of animal, and thus we have those same instincts, to reign supreme over other men, to get the best mate, to own the most etc. The only reason it is not excusable in humans is that we have the ability to rationalise.\n\nWe can realise that something we are doing is fundenmentally wrong, and yet we still do it. And that sucks. Because if everyone used their minds a bit more, they would realise we don't have to behave like greedy animals to get along in this world.