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Full-Text Articles in Arts and Humanities
Computed Tomography Shows High Fracture Prevalence Among Physically Active Forager-Horticulturalists With High Fertility, Jonathan Stieglitz, Benjamin C. Trumble, Horus Study Team, Caleb E. Finch, Dong Li, Matthew J. Budoff, Hillard Kaplan, Michael D. Gurven
Computed Tomography Shows High Fracture Prevalence Among Physically Active Forager-Horticulturalists With High Fertility, Jonathan Stieglitz, Benjamin C. Trumble, Horus Study Team, Caleb E. Finch, Dong Li, Matthew J. Budoff, Hillard Kaplan, Michael D. Gurven
ESI Publications
Modern humans have more fragile skeletons than other hominins, which may result from physical inactivity. Here, we test whether reproductive effort also compromises bone strength, by measuring using computed tomography thoracic vertebral bone mineral density (BMD) and fracture prevalence among physically active Tsimane forager-horticulturalists. Earlier onset of reproduction and shorter interbirth intervals are associated with reduced BMD for women. Tsimane BMD is lower versus Americans, but only for women, contrary to simple predictions relying on inactivity to explain skeletal fragility. Minimal BMD differences exist between Tsimane and American men, suggesting that systemic factors other than fertility (e.g. diet) do not …
The Dynamics Of Men's Cooperation And Social Status In A Small-Scale Society, Christopher Von Rueden, Daniel Redhead, Rick O'Gorman, Hillard Kaplan, Michael Gurven
The Dynamics Of Men's Cooperation And Social Status In A Small-Scale Society, Christopher Von Rueden, Daniel Redhead, Rick O'Gorman, Hillard Kaplan, Michael Gurven
ESI Publications
We propose that networks of cooperation and allocation of social status co-emerge in human groups. We substantiate this hypothesis with one of the first longitudinal studies of cooperation in a preindustrial society, spanning 8 years. Using longitudinal social network analysis of cooperation among men, we find large effects of kinship, reciprocity and transitivity in the nomination of cooperation partners over time. Independent of these effects, we show that (i) higher-status individuals gain more cooperation partners, and (ii) individuals gain status by cooperating with individuals of higher status than themselves. We posit that human hierarchies are more egalitarian relative to other …