Primates that live with many others know not to steal food when someone is watching
Tony Camacho/Science Source
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Never turn your back on a lemur — especially if it’s a member of a big gang.
Lemur species that live in large groups can tell when to steal food from a competitor in a lab experiment, researchers report June 26 in PLOS ONE. The finding supports the idea that brainpower in primates evolved to fit their complex social lives. Because the sneakier lemurs don't have bigger brains than less sneaky ones living in smaller groups, researchers suggest that social smarts don’t always depend on brain size.
Much of the evidence for sociality’s role in the evolution of intelligence comes from indirect measures