Did Homo sapiens benefit from the evolution of a fine sense of smell? Researchers who analysed the shape of fossil skulls from Neanderthals, modern humans and their ancestors say that the idea is plausible.
Markus Bastir at the Spanish National Museum of Natural Sciences in Madrid and his colleagues used three-dimensional surface-shape analysis to measure the internal dimensions of 14 skulls. They found shape differences suggestive of larger olfactory bulbs and temporal lobes in the area where the base of the brain would have rested in H. sapiens compared with other hominins.
The temporal lobes are involved in emotion, memory and social functions, and receive direct input from the olfactory bulbs. Inflated size of both may reflect increased links between smell and social functions. This might have yielded survival advantages by promoting social learning and odour-related modulation of behaviour, tightening bonds between group members, say the authors.