Are we getting dumber?

Researchers face a mystery: why our brains are shrinking

Our brains are smaller than those of our ancestors - why is still unclear.

(Bild: Krone KREATIV/Olena, jolygon, onimate – stock.adobe.com)

The brain of modern humans is around 13 percent smaller than that of Homo sapiens, who lived around 100,000 years ago. Opinions differ as to why this might be the case.

Traditionally, it is assumed that our large brains set us apart from other animals. Our ability to think and innovate enabled us to create the first art, invent the wheel and even land on the moon.

Compared to other animals of a similar size, our brains are very large indeed. In the six million years since our last common ancestor, the chimpanzee, the human brain has almost quadrupled in size.

However, studies show that this trend towards larger brains has been reversed in Homo sapiens. Over the last 100,000 years, the average brain size of our species has decreased. But why?