A popular theory among evolutionary biologists is that we have our sociability to thank for our big brains. This “social brain hypothesis” suggests that the mental effort involved in interacting with others eventually increased our cognitive capacity. However, the results of a study published Monday (March 27) in Nature Ecology & Evolution suggest that diet, rather than social complexity, is the key to bigger brains seen in some primates.
A team at New York University analyzed data on the diets and social lives of more than 140 primate species, including monkeys, apes, and lemurs. This revealed that measures of social complexity, such as group size or mating systems (monogamy vs. promiscuity) did not seem to contribute to bigger brains. But dietary preferences did. Most notably, ...
