Adaptive significance of small body size under poor socio‐economic conditions in southern Peru

Abstract The relationship of variations in parental body size to offspring survival has been studied in a population of poor socio‐economic conditions (“Barriada”) in the southern highland of Peru. Parents of small body size, especially mothers, had significantly greater per cent offspring survival than parents with larger body size. In other words, the offspring survival effectiveness of subjects of small body size was greater than that of subjects of large body size. It is postulated that the greater offspring survival effectiveness associated with small parental body size may reflect possible adaptive responses to poor socio‐economic conditions.