What is the source for our morals?

[Mechaghostman2]

Obviously objective morality doesn't exist considering everyone has a different opinion on what they think is moral. However, considering most of us don't go around killing and raping people, I'd have to say there is a dominant thought process we all share that could be considered universal morality. Chimpanzees and other higher mammals also exhibit this morality, albeit on a smaller scale. So did we evolve our basic morals as some kind of preservation of our species? Or is it completely learned behavior; rules created by tyrants that become memes? Or perhaps both? Is there a part of our brain that we have found to contain morality?