It killed off the slightly less violent and the slightly less ruthless. Those who where more so survived (and less subject to pain), as did their DNA. As for c

It killed off the slightly less violent and the slightly less ruthless. Those who where more so survived (and less subject to pain), as did their DNA. As for countries and war-like...that doesn't seem to be limited by geography and/or DNA. The species generally prefers violence. World history teaches us that. Sure, there are exceptions but they are rare.