They were evolved for a world in which people lived in very small groups, rarely met anybody who was terribly different from themselves, had rather short lives in which there were few choices and the highest priority was to eat and mate today.
De blev udviklet til en verden hvor mennesker boede sammen i meget små grupper, sjældent mødte nogen der var meget anderledes end sig selv, havde ret korte liv, med færre valg involveret og den højeste prioritet var at spise og parre sig i dag.