Female bone physiology resilience in a past Polynesian Outlier community.

Remodelling is a fundamental biological process involved in the maintenance of bone physiology and function. We know that a range of health and lifestyle factors can impact this process in living and past societies, but there is a notable gap in bone remodelling data for populations from the Pacific Islands. We conducted the first examination of femoral cortical histology in 69 individuals from ca. 440-150 BP Taumako in Solomon Islands, a remote 'Polynesian Outlier' island in Melanesia. We tested whether bone remodelling indicators differed between age groups, and biological sex validated using ancient DNA. Bone vascular canal and osteon size, vascular porosity, and localised osteon densities, corrected by femoral robusticity indices were examined. Females had statistically significantly higher vascular porosities when compared to males, but osteon densities and ratios of canal-osteon (~ 8%) did not differ between the sexes. Our results indicate that, compared to males, localised femoral bone tissue of the Taumako females did not drastically decline with age, contrary to what is often observed in modern populations. However, our results match findings in other archaeological samples-a testament to past female bone physiology resilience, also now observed in the Pacific region.

Strontium (87 Sr/86 Sr) isotope analysis of the Namu skeletal assemblage: A study of past human migration on Taumako, a Polynesian Outlier in the eastern Solomon Islands.

OBJECTIVES: This study aims to assess if inter-island mobility can be identified during the Namu period (ca. 1,510-1800 AD) using 87 Sr/86 Sr analysis of dental enamel for individuals from the Namu burial ground on Taumako Island in the eastern Solomon Island Chain. Historic evidence from this region suggests that females migrated between the Duff, Reef, and Santa Cruz islands for marriage purposes. We hypothesize that observable trends in migrational (87 Sr/86 Sr) and dietary (δ13 C and δ15 N) isotopes can reveal the relationship between demographic factors, social status, diet, and female mobility on Taumako. METHODS: This research analyzes enamel 87 Sr/86 Sr for 58 individuals in the Namu skeletal sample. The 87 Sr/86 Sr results were compared with published dietary isotope data (bone collagen and dentin δ13 C and δ15 N values) and type/number of grave goods to assess whether trends within the data may be related to sex, age, or burial wealth. RESULTS: The results show that females display significantly higher 87 Sr/86 Sr values compared to males. One young adult female displayed a 87 Sr/86 Sr value that was +2SD outside the mean for the sampled individuals. A linear mixed-effects model and principle components analysis of 87 Sr/86 Sr, δ13 C, and δ15 N values suggest that wealth, sex, and age-cohort membership have an observable influence on the isotopic variation for the Taumako population. CONCLUSION: We suggest that during the Namu period, Taumako was patrilocal and that some females migrated there from the nearby Santa Cruz and Reef islands. One female immigrated to Taumako from a geologically distinct region outside of the Duff, Reef, and Santa Cruz Island groups.

Language continuity despite population replacement in Remote Oceania.

Recent genomic analyses show that the earliest peoples reaching Remote Oceania-associated with Austronesian-speaking Lapita culture-were almost completely East Asian, without detectable Papuan ancestry. However, Papuan-related genetic ancestry is found across present-day Pacific populations, indicating that peoples from Near Oceania have played a significant, but largely unknown, ancestral role. Here, new genome-wide data from 19 ancient South Pacific individuals provide direct evidence of a so-far undescribed Papuan expansion into Remote Oceania starting ~2,500 yr BP, far earlier than previously estimated and supporting a model from historical linguistics. New genome-wide data from 27 contemporary ni-Vanuatu demonstrate a subsequent and almost complete replacement of Lapita-Austronesian by Near Oceanian ancestry. Despite this massive demographic change, incoming Papuan languages did not replace Austronesian languages. Population replacement with language continuity is extremely rare-if not unprecedented-in human history. Our analyses show that rather than one large-scale event, the process was incremental and complex, with repeated migrations and sex-biased admixture with peoples from the Bismarck Archipelago.