The first fully modern human skull appears in sub-Saharan Africa about 195,000 years go. It probably belonged to a population with an average IQ around 80. But it was surrounded by archaic humans with IQs in the 70s or less.

It wasn’t until about 70,000 years ago that the second fully modern human skull appears in the fossil record. It seems fully moderns (IQ 80+) were incredibly rare for our first 125,000 years.

About 70,000 years ago, modern humans began a massive exodus out of Africa. Richard Klein believes a sudden increase in intellect allowed this exodus. I believe this exodus is what caused the sudden increase in intellect, because by leaving the tropics, we had to be smart enough to survive the cold, something we hadn’t done in over 25 million years.

By 40,000 years ago, the first humans had reached the arctic and around the same time, real art first appears in the archeological record. The first populations with a mean IQ in the triple digits had appeared:

Art from 39,000 years ago

Some would stay in Europe and become the Whites. Others would freeze further and become 103 IQ Northeast Asians.

Some would cross over to the New World where they became the Native Americans. This tiny group found two whole fertile continents all to themselves that was teaming with Megafauna that had never before been hunted. These huge beasts were so easy to catch that folks didn’t need their triple digit IQs to survive and since the brain is so metabolically expensive, they began to regress to an IQ of 86. A rare evolutionary reversal.

There’s been virtually no further change in human IQ in the last 10,000 years with the exception of Ashkenazi Jews (and perhaps some casts in India) who rapidly evolved to IQ 110 during the last few millennia.

It’s only a small exaggeration to say our species stopped evolving 40,000 years ago.

And yet look how much the World has changed since then. Because of the cultural leap that occurred 40,000 years ago, humans are the only species with an extended phenotype that constantly reinvents itself, even in the face of genotypic stagnation.