How long has unschooling been around?

Someone on the Unschooling Basics list asked, "How long has unschooling been around?"

Kelly Lovejoy responded:

Since humans have roamed the planet and before. Even Neanderthals learned!
Deb Lewis concurred:
Yes, learning is so easy, even cave men did it. HEY! This is fun!

There seems to be no shortage of evidence that humans learn.

Deb Lewis

More of any of this?
More Deb Lewis History Connections Learning vs. Teaching