A group of genes that is found only in humans and arose in our ancestors 3–4 million years ago may have driven the evolution of our bigger brains.

This revelation — and the work that led up to it — is the subject of two studies now reported in the journal Cell.

One study was led by the University of California (UC) Santa Cruz, and the other was led by the Université Libre de Bruxelles in Belgium.

The findings plug a gap in our knowledge about the changes that drove the evolution of our larger brains and gave us the ability to think and solve problems.

The genes — named NOTCH2NL — belong to a very old family called Notch that was first identified in fruit flies; they got their name because they were linked to genetic faults that caused the flies to have notched wings.

How NOTCH2NL increases neuron numbers

Notch genes go back “hundreds of millions of years” and “play important roles in embryonic development,” says David Haussler, who is a professor of biomolecular engineering at UC Santa Cruz and co-senior author of the first study paper.

[ Read More ]