Rodrigo Pérez Ortega in Science:
We humans are proud of our big brains, which are responsible for our ability to plan ahead, communicate, and create. Inside our skulls, we pack, on average, 86 billion neurons—up to three times more than those of our primate cousins. For years, researchers have tried to figure out how we manage to develop so many brain cells. Now, they’ve come a step closer: A new study shows a single amino acid change in a metabolic gene helps our brains develop more neurons than other mammals—and more than our extinct cousins, the Neanderthals.
The finding “is really a breakthrough,” says Brigitte Malgrange, a developmental neurobiologist at the University of Liège who was not involved in the study. “A single amino acid change is really, really important and gives rise to incredible consequences regarding the brain.”