Why Grandmothers May Need Large Brains. (Commentary on Skoyles on Brain Expertise)NicholasHumphreyauthorSkoyles's case against human brain size being related to IQ is strong; but his case in favor of its being related to expertise is weak. I propose that the explanation for the evolutionary expansion of the human brain in fact lies far away, in the need to have a brain that could continue to function into old age.Animal CognitionPhysiological PsychologyPsycoloquySociobiologyEvolutionary PsychologyBehavioral Neuroscience1999Journal (On-line/Unpaginated)