Palaeodiet and Infant Feeding in Coastal Arctic Settlements : Insights from stable isotope analysis of bone and dentine collagen and amino acids

This dissertation investigates the day-to-day activities that sustained human societies in the arctic and subarctic environments of North America and Siberia over the past 1500 years. Maintenance activities, such as food preparation, childcare, and the care of domestic animals, are commonly inflected by social identity and can provide insight into the experience of gender among archaeological and historical populations. This PhD combined stable isotope analysis of bulk bone collagen and single amino acids, with ethnographic research and ancient DNA analysis to answer a number of research questions, such as, how can the effects of destructive biomolecular sampling protocols be minimized?; how were sled dogs provisioned across the Arctic?; how can palaeodietary research inform our understanding of social relationships between humans and dogs?; how long were human infants breastfed among Bering Sea hunter-gatherers? The dissertation is comprised of five studies: a review of stable isotope studies of late Holocene Arctic populations; a methodological paper presenting a best practice for the pre-treatment of humic-contaminated bone samples, and three bioarchaeological applications that variously employ stable isotope analysis of bulk bone collagen, DNA analysis of dog furs, and isotopic analysis of amino acids. The isotopic evidence for dog diets largely corresponds to zooarchaeological and ethnographic evidence for local subsistence practices. Dog bones dating to between the 15th and 19th centuries, from coastal Labrador, Canada, carried a strong marine isotope signature as did dog furs collected during the early 20th century in Greenland, coastal Labrador, and Alaska. Dogs living among reindeer herders in early 20th century Siberia consumed terrestrial protein sources, while those on the Kamchatka Peninsula consumed terrestrial protein supplemented by limited quantities of salmon. Dog provisioning required considerable human labour and was an important structuring component of daily life in the Arctic. The final study presents the first analysis of infant feeding practices among prehistoric hunter-gatherers of the Bering Sea coast. This study uses stable isotope analysis of bulk collagen from dentine increments to show that breastfeeding and weaning practices varied considerably across the sampled group. The novel isotopic analysis of amino acids from dentine suggests those amino acids, such as lysine, that are routed directly from diet to collagen, show promise for distinguishing between the dual influences of diet and systemic stress on the nitrogen isotope values of human proteins. In the thesis summary, I also include a discussion of the ethics of bioarchaeological practice. Indigneous Arctic cultures are frequently the focus of archaeological study in Canada, Scandinavia, the United States, and Russia, but among these regions, the legislation designed to protect Indigenous cultural heritage differs dramatically. In light of the increasing number of bioarchaeological studies conducted in Siberia, I review regional differences in the codes of bioarchaeological practice and, drawing on bioarchaeological research in other international contexts, suggest some possible solutions for future work. Due to Covid-19, the thesis defence will be held digitally on the Zoom platformArchSci202