人类之光-天生的运动健将

Every man alive today shares a portion of his DNA. Two inches taller than a modern american, a natural athlete, a born hunter.

This is his home. The Rift Valley of East Africa. A fertile laboratory for life. In his sights, a thousand pounds of meat.

Enough to feed his family of six for a month. Soon there will be seven, The woman he shares his life with. Is expecting their first child.

Stereoscopic vision to accurately judge distance. Dexterous hands. Speed on two legs. But he has none of the natural weapons of Africa's other predators.

He can't outrun a cheetah. Nowhere near the strength of a lion. Or the bone-crushing jaws of a hyena. So he invents. Tools make me better, Weapons make me more powerful.

You have to be on two feet. You have to free up your hands. And freeing up your hands to work with tools changes the game.

And there's no other species on this planet that committed to weapon use and tool use like us.