Primate brain size is predicted by diet, rather than multiple measures of sociality, according to a recent study controlling for body size and phylogeny, which conflicts with the social brain hypothesis, that posits that social complexity is the primary driver of primate cognitive complexity.

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Primate brain size is predicted by diet, rather than multiple measures of sociality, according to a recent study controlling for body size and phylogeny, which conflicts with the social brain hypothesis, that posits that social complexity is the primary driver of primate cognitive complexity.