Sex differences in food preferences, eating frequency, and dental attrition of the Hadza

This dissertation focuses on a few possible causes and consequences of the sexual division of foraging labor in the Hadza, hunter-gatherers of Tanzania. I present three separate studies; the investigation of foraging goals as reflected in food preferences, the extent of cross-sex food sharing as reflected in consumption, and the consequences as reflected in evidence of the sexual division of foraging labor that would be detectable in the archaeological record.;Food preferences are important for understanding foraging choices. In studying human foragers rather than other animals, we have the advantage of being able to ask them which foods they prefer. Yet surprisingly, no studies of systematically collected data exist on human forager food preferences. The Hadza of Tanzania are full-time foragers in an area where the hominin record extends back to 3--4 million years ago, so their diet is very relevant for understanding the paleo-diet. The first study reports on their food preferences, elicited with photographs of species within the five major food categories in their diet: honey, meat, berries, baobab, and tubers. There were sex differences in the ranks of two food categories: meat and berries. While male and female ranks agreed on the other three food categories, females ranked berries second and meat fourth, whereas males ranked meat second and berries fourth. Theses similarities and differences are interesting in light of the fact that the sexes target different foods.;My second study uses eating frequency data from instantaneous scan observations of the Hadza, hunter-gatherers of Tanzania, to see to how much sharing of foods taken back to camp compensates for the targeting of different foods by each sex while out foraging. I find that eating in camp differs by sex in terms of overall eating frequency, as well as in terms of diet composition (frequencies of eating each food type). I also control for sex-differences in time spent in camp and still find sex-differences in eating frequencies---women are observed eating significantly more frequently than men. There are also sex-differences in the eating frequencies of particular food types both with and without controlling for presence in camp. Finally, I use data on acquisition of each food type by sex and find that both sexes are more frequently observed eating women's foods in camp than men's foods.;My third study investigates the relationship between patterns of attrition across age and sex cohorts with behavioral data on diet composition in a contemporary hunter-gatherer population, the Hadza of Tanzania. Despite the targeting of different foods by males and females among hunter-gatherers, the sharing of male and female foods is usually assumed to result in virtually the same diet for males and females. Despite the widespread sharing of foods among the Hadza, hunter-gathers of Tanzania, women were observed eating significantly more frequently than Hadza men, and were eating more of some foods than others. Casts of the upper dentition (full arcade) were made from molds taken from 126 adults (71 women and 55 men) and scored according to the Murphy dental attrition scoring system. Females demonstrated significantly greater anterior occlusal wear than males controlling for age. Males demonstrated greater asymmetry in wear, with greater wear on the left side in canines, first premolars, and first molars. I believe that these sex differences in wear patterns reflect the sex differences seen in eating frequency, as well as differences in the use of teeth as tools.