Biological and Physical Anthropology Commons^™

Salivary Microbiomes Of Indigenous Tsimane Mothers And Infants Are Distinct Despite Frequent Premastication, Cliff S. Han, Melanie Ann Martin, Armand E.K. Dichosa, Ashlynn R. Daughton, Seth Frietze, Hillard Kaplan, Michael D. Gurven, Joe Alcock

ESI Publications

Background. Premastication, the transfer of pre-chewed food, is a common infant and young child feeding practice among the Tsimane, forager-horticulturalists living in the Bolivian Amazon. Research conducted primarily with Western populations has shown that infants harbor distinct oral microbiota from their mothers. Premastication, which is less common in these populations, may influence the colonization and maturation of infant oral microbiota, including via transmission of oral pathogens. We collected premasticated food and saliva samples from Tsimane mothers and infants (9-24 months of age) to test for evidence of bacterial transmission in premasticated foods and overlap in maternal and infant salivary …

Calcaneal Quantitative Ultrasound Indicates Reduced Bone Status Among Physically Active Adult Forager-Horticulturalists, Jonathan Stieglitz, Felicia C. Madimenos, Hillard Kaplan, Michael Gurven

ESI Publications

Six months of exclusive breastfeeding (EBF) is considered optimal for infant health, though globally most infants begin complementary feeding (CF) earlier—including among populations that practice prolonged breastfeeding. Two frameworks for understanding patterns of early CF emerge in the literature. In the first, maternal and infant needs trade-off, as “maternal-centric” factors—related to time and energy demands, reproductive investment, cultural influences, and structural barriers— favor supplanting breastfeeding with earlier and increased CF. A second framework considers that “infant-centric” factors—related to infant energetic needs—favor CF before six months to supplement breastfeeding.

We apply these two frameworks in examining early CF among the Tsimane—a …