Years ago, a student asked anthropologist Margaret Mead what she considered to be the first sign of human civilization. The student expected Mead to talk about fishhooks or clay pots or grinding stones.

But no. Mead said that the first sign of civilization was a femur 1/ that had been broken and then healed. Mead explained that in the animal kingdom, if you break your leg, you die. You cannot run from danger, get to the river for a drink or hunt for food. You are meat for prowling beasts.

A broken femur that has healed is evidence that someone