I require new mountains

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Natural selection never favors excess; if a lower-cost solution is present, it is selected for. Intelligence is a hugely costly trait. The human brain is responsible for 25 per cent of total glucose use, 20 per cent of oxygen use and 15 per cent of our total cardiac output, although making up only 2 per cent of our total body weight. Explaining the evolution of such a costly trait has been a long-standing goal in evolutionary biology, leading to a rich array of explanatory hypotheses, ranging from evasion of predators to intelligence acting as an adaptation for the evolution of culture. Among the proposed explanations, arguably the most influential has been the “social intelligence hypothesis,” which posits that it is the varied demands of social interactions that have led to advanced intelligence.

{ Proceedings of The Royal Society B | Continue reading }