【英语时差8,16】成吉思汗（上）（在线收听）

Today, Afghanistan is a war-torn region, battled over by military forces and world-spanning empires. Eight hundred years ago things were much the same. Only then, there was only one ruler: Genghis Khan. Khan is one of the greatest conquerors who ever lived. Before he was finished, he had created an empire that ran all the way from the Caspian Sea to the Sea of Japan. That’s the history portion of our segment. Now, on to the science. What is it that powerful males of the human species are after when they overrun other males? From an evolutionary point of view, the major objective is to spread their genes more effectively. And surprising, new data suggest Khan may have done that more successfully than anyone imagined.