N.G. Blurton Jones

Hadza Women's Time Allocation, Offspring Provisioning, and the Evolution of Long Postmenopausal Life Spans

Extended provisioning of offspring and long postmenopausal life spans are characteristic of all modern humans but no other primates. These traits may have evolved in tandem. Analysis of relationships between womens time allocation and childrens nutritional welfare among the Hadza of northern Tanzania yields results consistent with this proposition. Implications for current thought about the evolution of hominid food sharing, life history, and social organization are discussed.

Reanalysis of large mammal body part transport among the Hadza

Abstract Data on 54 cases of large mammal body part transport among the Hadza are reanalysed. Results are consistent with those previously reported. Within species, parts are ranked on a uni-dimensional scale for transport: high ranked parts are more likely to be moved from kill sites to base camps, low ranked parts less likely. For most species in the sample, rank order is inconsistent with that described in the widely cited White/Perkins and Daly model. Archaeological interpretations based on this aspect of the model are therefore suspect. The number of parts moved from Hadza kills varies with transport costs, measured by carcass size and/or kill site-base camp distance. This result fits predictions from the White/Perkins and Daly model. Further application of these results to archaeological problems requires that the Hadza pattern be explained in general terms. The potential relevance of a transport model recently formulated by Metcalfe is noted.

Hunting and nuclear families: some lessons from the Hadza about men's work

Hadza hunter-gatherers display economic and social features usually assumed to indicate the dependence of wives and children on provisioning husbands and fathers. The wives and children of better Hadza hunters have been found to be better-nourished, consistent with the assumption that men hunt to provision their families. Yet, as is common among foragers, the Hadza share meat widely. Analyses of meat-sharing data confirm that little of the meat from large prey went to the hunters own household. These analyses also show that neither a mans hunting success nor the time he spent hunting made any difference in how much meat his family got from the kills of others. Here we address questions posed by this set of observations. What explains the better nutrition of the children of better hunters if they did not get differential rations of meat? If better hunters got no more meat for their effort and poorer hunters were not punished with less, what incentive could account for the continuing disproportionate contribution that some men made to the groups nutrition? If women were not dependent on their husbands hunting success for meat, an obvious incentive for women to marry hunters disappears. We briefly consider the implications of these patterns for the evolution of marriage and nuclear families.

Hunting and Nuclear Families

Hadza hunter-gatherers display economic and social features usually assumed to indicate the dependence of wives and children on provisioning husbands and fathers. The wives and children of better Hadza hunters have been found to be better-nourished, consistent with the assumption that men hunt to provision their families. Yet, as is common among foragers, the Hadza share meat widely. Analyses of meat-sharing data confirm that little of the meat from large prey went to the hunters own household. These analyses also show that neither a mans hunting success nor the time he spent hunting made any difference in how much meat his family got from the kills of others. Here we address questions posed by this set of observations. What explains the better nutrition of the children of better hunters if they did not get differential rations of meat? If better hunters got no more meat for their effort and poorer hunters were not punished with less, what incentive could account for the continuing disproportionate contribution that some men made to the groups nutrition? If women were not dependent on their husbands hunting success for meat, an obvious incentive for women to marry hunters disappears. We briefly consider the implications of these patterns for the evolution of marriage and nuclear families.