No sex differences on efficiency in gathering activities during puberty

Abstract

Sexual division of labor is well-known in small-scale societies. In sub-adult hunter-gatherers, this division onsets with the puberty (Lew-Levy et al., 2017), but, apparently, there is no physiological explanation for this beginning. The present study uses an experimental energetic approach to evaluate possible sexual differences in gathering related activities. The energy cost of gathering related activities was measured in 42 subjects, of both sexes aged between 8-14, and body mass and other anthropometric variables were recorded. Our results show that the energetic differences in the simulated gathering activities, depends only on body mass. According to this result, both sexes are equally efficient in aerobic-locomotion activities like gathering. In this line, and discarding the energetic factor, the sex division of labor could be explained as a necessary adaptation to develop, as soon as possible, complex activities required during adulthood (Gurven et al., 2009). Moreover, attending to these results, it can be said that carrying out gathering activities during childhood and adolescence is favored by the growth and development cycles of Homo sapiens. If most of the energy cost of gathering activities depends on body mass, the delayed human growth allows sub-adults to practice them for longer and better, to acquire adults’ complex-skills (Kaplan et al., 2000), without requiring a high energetic cost, easily subsided by other members of the group (Bogin, 1997; Kramer and Greaves, 2011).