Crying in !Kung San infants: a test of the cultural specificity hypothesis.

The pattern of crying and fretting behavior during the first two years is described for 46 !Kung San infants from a hunter-gatherer society in northwestern Botswana. Despite markedly different caretaking practices predisposing to quieter infants, crying and fretting were significantly greater during the first three months, and a peak pattern was present. Measurement of crying 'intensity' indicated that it was predominantly short and fretful. The results support the concept that the early peak pattern is not specific to infants in western industrialized societies, and may represent a behavior universal to the human species. The caretaking differences between societies primarily appear to affect crying duration rather than its frequency and pattern in early infancy.