The article by Reader and Laland explores the relationship between brain size, cognitive capacity, and behavioral flexibility in primates. They use ecologically relevant measures such as behavioral innovation, social learning, and tool use to demonstrate that brain size and cognitive capacity are positively correlated. A comparative analysis of 533 instances of innovation, 445 observations of social learning, and 607 episodes of tool use showed that these behaviors are positively correlated with species' relative and absolute "executive" brain volumes, after controlling for phylogeny and research effort. The findings suggest that social learning, innovation, and tool use frequencies covary across species, challenging the view of an evolutionary tradeoff between individual experience and social cues. The study provides empirical evidence linking behavioral innovation, social learning capacities, and brain size in mammals, suggesting that these abilities may have played a pivotal role in primate brain evolution. The authors also discuss the implications of their findings for various hypotheses about primate brain evolution, including those emphasizing social intelligence and ecological explanations.The article by Reader and Laland explores the relationship between brain size, cognitive capacity, and behavioral flexibility in primates. They use ecologically relevant measures such as behavioral innovation, social learning, and tool use to demonstrate that brain size and cognitive capacity are positively correlated. A comparative analysis of 533 instances of innovation, 445 observations of social learning, and 607 episodes of tool use showed that these behaviors are positively correlated with species' relative and absolute "executive" brain volumes, after controlling for phylogeny and research effort. The findings suggest that social learning, innovation, and tool use frequencies covary across species, challenging the view of an evolutionary tradeoff between individual experience and social cues. The study provides empirical evidence linking behavioral innovation, social learning capacities, and brain size in mammals, suggesting that these abilities may have played a pivotal role in primate brain evolution. The authors also discuss the implications of their findings for various hypotheses about primate brain evolution, including those emphasizing social intelligence and ecological explanations.