Our big brains, our language ability, and our intelligence make us uniquely human.

But barely 10,000 years ago (a mere blip in evolutionary time) human-like creatures called "Boskops" flourished in South Africa. They possessed extraordinary features: forebrains roughly 50% larger than ours, and estimated IQs to match--far surpassing our own. Many of these huge fossil skulls have been discovered over the last century, but most of us have never heard of this scientific marvel.