Foraging, Food Sharing, and Family Formation among the Hadza

Harvard University, Cambridge MA

Investigators

Abstract

0242455 Marlowe The tiny number of hunting and gathering societies left in the world will soon disappear and with them our chance to study behavior associated with the hunting and gathering niche. This longitudinal study examines foraging and food sharing, and their impact on the formation of the nuclear family among one of these societies, the Hadza of Tanzania. The Hadza have no formal marriage ceremony but form long-term pair bonds and are serially monogamous. Like many foragers in warm climates women bring in more food calories than men, and the food men bring in is acquired much less regularly and is more widely shared outside the household. This forces us to question the long-held view that a man's provisioning is what promotes pair bonds. About 160 Hadza in four nomadic camps of roughly 40 people each will be observed over the course of three years by a human behavioral ecologist, along with graduate anthropology students from Harvard and the University of Dar es Salaam, Tanzania. The researchers will collect data on the foraging activities and food acquired by all people, how much of which foods they eat while foraging, how much they take back to camp, and how much is shared with others within and outside the household in order to evaluate what role male provisioning may play in maintaining pair bonds. A previous study found no effect of father absence on child mortality among the Hadza. However, a cross-cultural analysis of foraging societies showed that men's contribution to the diet mainly affects women's fertility rather than offspring survivorship. Previous data reveal that Hadza men bring in more food when their wives are nursing and this study will investigate the effects men's provisioning has on mortality, time to weaning, time to next child, and overall fertility rates. Broader impacts of this research include a better understanding of what explains the universality of pair bonds among humans. Examination of the causes and consequences of divorce will shed light on the importance of families and emotional attachment. The nutritional analysis of Hadza foods, the energetic analysis of their acquisition, and the economic analysis of their pattern of sharing will further our knowledge of human health under naturalistic conditions. By supporting students in extended field settings, the project combines education and research.