Let me put it simply that I don't believe what you guys are saying is true. i believe in this positive side of human nature, that we are not that selfish, uncivilized barbaric cannibals we once were. The raw survivalist instincts that drove our ancestors to torture, murder and plunder, to ensure their tribes stayed alive in a harsh wild world, grabbing any resources available, are being suppressed or replaced by the better or positive side of human nature. The xenophobic, territorial, hateful, murderous, warmongering animal urges while are still very much alive in most of us, now remain subdued, hidden, diluted and tamed because of our development, our understanding, our globalization, our management of world resources that help strengthened altruism, cooperation, morality, love, compassion etc .. To take the argument further, surely the relative peace and crime free world we enjoy now, as compared to say 2K years ago where human lives were cheaper, brutality were much more rampant, murder was as easy as killing a cat, we must have changed something in us. We have 6 billion people in the world today much more than anytime in history, living in packed cities with relative comfort and contentment. How could we do that if we have so much negativity in our lives every day for the past hundreds of years over tens of generations?

Hence there are always balances in life, when say, your basic needs like food and water are threatened, you could transform from a loving compassionate altruistic human to a barbaric selfish cannibal trying to keep your family alive. We are not there today, we may be someday. We must diligently work on not letting this day come to us.