Assessing the association between subsistence strategies and the timing of weaning among indigenous archaeological populations of the Caribbean

Abstract

Human breastfeeding is a biocultural process shaped by the interaction of numerous biological, cultural, economic, and social factors. Although previous studies have found that a society's subsistence economy alone does not determine weaning timing, subsistence may still have a profound effect on weaning food choices. This paper analyses nitrogen and carbon stable isotopes in bone collagen and apatite of individuals from six precolonial Caribbean sites grouped into four subsistence categories: Hunter‐Fisher‐Gatherers (Cueva del Perico I and Cueva Calero, Cuba), Horticulturalists (Canímar Abajo, Cuba), Agriculturalists from the Antilles (Paso del Indio, Puerto Rico), and Agriculturalists of Mesoamerica (Marco Gonzalez and San Pedro, Belize) in order to explore how subsistence economy affected the different groups' breastfeeding and weaning practices. Ages for the start and the end of weaning, and the isotopic characteristics of possible food sources used as supplements during the weaning process, were assessed using the Bayesian probability model “Weaning Age Reconstruction with Nitrogen isotopes.” Model results indicate (a) a major dietary change around 2 years of age for most of the study populations, (b) that supplements seem to have been introduced into nonadults diet at earlier ages than has been observed in ethnographic populations of the area, (c) no direct correlation between the start of weaning and the availability of cultigens, but (d) that groups that had access to cultigens would appear to have weaned their children using foods with lower nitrogen isotope values, suggesting that plants (likely domesticates) may have had an important role as weaning foods.

Exploring ideas about isotopic variation in breastfeeding and weaning within and between populations: Case studies from the American midcontinent

“…There was also no apparent difference in fertility between the sites based on palaeodemographic estimates (Schurr & Powell, ). Similar results have since been obtained in a comparison of weaning times for archaeological populations from the Caribbean that included hunter‐gatherer‐fishers and several types of agriculturalists (Chinique de Armas and Pestle, ). They found no correlation between the start of weaning and the availability of cultigens.…”

Reconstructing breastfeeding and weaning practices in the Bronze Age Near East using stable nitrogen isotopes

“… t 1 and t 2 ages in a global comparison of previous WARN studies (Chinique de Armas & Pestle, ; King, Millard, et al, ; Smith et al, ; Tsutaya & Yoneda, ) Global average with ±1 SD shown…”

“…Compiling those studies that have used WARN to calculate weaning and complete weaning times (Chinique de Armas & Pestle, ; King et al, ; Smith, Pestle, Clarot, & Gallardo, ; Tsutaya, ), t 1 MDE averages 1.1 ± 0.8 and t 2 MDE averages 3.0 ± 1.3. This places this study's t 1 results earlier than most other sites and the t 2 values around the global average (Figure ).…”

Tracking breastfeeding and weaning practices in ancient populations by combining carbon, nitrogen and oxygen stable isotopes from multiple non-adult tissues

“…Outputs of the WARN model simulation includes maximum density estimators and posterior probabilities for: the start of weaning (t 1 , the age at which food other than mother’s milk is first added to the infant’s diet), the end of weaning (t 2 , when breast milk is no longer provided), as well as the δ 15 N value (δ 15 N wnfood ) of weaning foods, and E, the nitrogen isotope enrichment between mother and child [ 24 ]. Bayesian modeling approaches [ 79 ] are being increasingly used for dietary reconstructions [ 47 ], including BWPs [ 8 , 9 , 22 , 24 ]. They offer advantages over ad hoc explanations since conclusions are based on probabilities rather than the use of fixed offsets to account for the difference in δ 15 N between bone collagen and diet.…”

“…Recent studies of BWPs in Caribbean populations combined the analysis of δ 15 N and δ 13 C values in bone collagen with the use of Bayesian models to reconstruct the timing of weaning and the type of foods used during their weaning process [ 8 , 9 ]. The age at the start of weaning was found to be significantly later than observed in ethnographic populations from the area [ 43 – 45 ], or the age established by modern medical recommendations [ 46 ], an issue that had previously been observed when analyzing archaeological metadata more broadly [ 24 ].…”