A research group argues that a species’ number of neurons, rather than brain volume, should serve as indicator of cognitive capacity when studying brain evolution, but some experts voice doubts.
Impressions that ancient brains left in fossilized skulls reveal that the first human ancestors to migrate out of Africa had much more primitive brains than previously thought.
The animals kill off around one-quarter of the neurons in their somatosensory cortex, perhaps to save energy, and the cells appear to return the following summer.
Scans of eight fossilized adult and infant Australopithecus afarensis skulls reveal a prolonged period of brain growth during development that may have set the stage for extended childhood learning in later hominins.
An analysis of the contours of more than 600 kids’ brains points to links between cerebral surface area and heritability in regions of the brain important in cognition.
A bevy of genes known to be active during human fetal and infant development first appeared at the same time that the prefrontal cortex—the area of the brain associated with human intelligence and personality—took shape in primates.