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ABSTRACT: Stable carbon and nitrogen isotope analyses of bones and teeth at the ancestral heritage Muwekma Ohlone site of Yakmuy ́Ooyákma-tka (“Place of the East Ridge Site”; CA-SCL-215) reveal significant differences in the dietary life history of males and females. Overall, isotope data indicate that site inhabitants were primarily dependent on low-trophic-level foods, likely plants, and minor amounts of marine food for their main source of dietary protein. From tooth dentin serial samples, we found that males and females were similar for δ13C in early childhood (age 1–9 years), but boys were elevated in δ15N by 0.6–1.0‰ relative to girls, indicating boys were accessing slightly greater amounts of higher-trophic-level foods, such as meat from game. The sex-biased difference in δ15N diminishes during the second decade of life, as female δ15N values increase and become equal to males. However, a difference in δ13C emerges during the second decade: female δ13C values are elevated relative to males. This could indicate that teenage females consumed higher amounts of low-trophic-level, marine-derived protein, such as shellfish. During later adult years the difference in δ13C disappears, while males again show an increase in δ15N relative to females. Although these differences are small, they reveal important sex-biased life history patterns during childhood and adulthood in this ancient community.
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AGE OF WEANING AND POST-WEANING CHILDHOOD DIETS IN A LATE HOLOCENE PRECONTACT SITE, CA-SOL-11, NEAR SUISUN MARSH
We examine age of weaning and childhood diet at a Middle Period site in central California, CA-SOL-11, near Suisun Marsh. Stable isotope analyses of serial samples of permanent first molars record information about the diet of an individual when they were between 0 and 9.5 years of age. Our results show that females were breastfed, on average, slightly longer than males at the site. Because breastfeeding represents a significant time and caloric investment by a mother, this suggests greater parental investment in female offspring relative to males. After weaning, young males gained a greater proportion of protein from higher trophic levels and with greater contribution from brackish or marine environments, which we interpret as a higher quality diet. This suggests either preferential provisioning by parents in males after weaning, or evidence of gendered labor practices and diets beginning in early childhood. We also incorporate new analyses of the amelogenin proteins preserved in enamel, AMELX_HUMAN and AMELY_HUMAN, to estimate the sex of one individual previously identified as male based on osteological markers and two individuals that could not be assigned sex based on osteology
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- PAR ID:
- 10189619
- Date Published:
- Journal Name:
- Proceedings of the Society for California Archaeology
- Volume:
- 33
- ISSN:
- 0897-0947
- Page Range / eLocation ID:
- 196-210
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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