SciCombinator

Native American populations declined between 1492 and 1900 CE, instigated by the European colonization of the Americas. However, the magnitude, tempo, and ecological effects of this depopulation remain the source of enduring debates. Recently, scholars have linked indigenous demographic decline, Neotropical reforestation, and shifting fire regimes to global changes in climate, atmosphere, and the Early Anthropocene hypothesis. In light of these studies, we assess these processes in conifer-dominated forests of the Southwest United States. We compare light detection and ranging data, archaeology, dendrochronology, and historical records from the Jemez Province of New Mexico to quantify population losses, establish dates of depopulation events, and determine the extent and timing of forest regrowth and fire regimes between 1492 and 1900. We present a new formula for the estimation of Pueblo population based on architectural remains and apply this formula to 18 archaeological sites in the Jemez Province. A dendrochronological study of remnant wood establishes dates of terminal occupation at these sites. By combining our results with historical records, we report a model of pre- and post-Columbian population dynamics in the Jemez Province. Our results indicate that the indigenous population of the Jemez Province declined by 87% following European colonization but that this reduction occurred nearly a century after initial contact. Depopulation also triggered an increase in the frequency of extensive surface fires between 1640 and 1900. Ultimately, this study illustrates the quality of integrated archaeological and paleoecological data needed to assess the links between Native American population decline and ecological change after European contact.

A major factor for the population decline of Native Americans after European contact has been attributed to infectious disease susceptibility. To investigate whether a pre-existing genetic component contributed to this phenomenon, here we analyse 50 exomes of a continuous population from the Northwest Coast of North America, dating from before and after European contact. We model the population collapse after European contact, inferring a 57% reduction in effective population size. We also identify signatures of positive selection on immune-related genes in the ancient but not the modern group, with the strongest signal deriving from the human leucocyte antigen (HLA) gene HLA-DQA1. The modern individuals show a marked frequency decrease in the same alleles, likely due to the environmental change associated with European colonization, whereby negative selection may have acted on the same gene after contact. The evident shift in selection pressures correlates to the regional European-borne epidemics of the 1800s.

As dogs have traveled with humans to every continent, they can potentially serve as an excellent proxy when studying human migration history. Past genetic studies into the origins of Native American dogs have used portions of the hypervariable region (HVR) of mitochondrial DNA (mtDNA) to indicate that prior to European contact the dogs of Native Americans originated in Eurasia. In this study, we summarize past DNA studies of both humans and dogs to discuss their population histories in the Americas. We then sequenced a portion of the mtDNA HVR of 42 pre-Columbian dogs from three sites located in Illinois, coastal British Columbia, and Colorado, and identify four novel dog mtDNA haplotypes. Next, we analyzed a dataset comprised of all available ancient dog sequences from the Americas to infer the pre-Columbian population history of dogs in the Americas. Interestingly, we found low levels of genetic diversity for some populations consistent with the possibility of deliberate breeding practices. Furthermore, we identified multiple putative founding haplotypes in addition to dog haplotypes that closely resemble those of wolves, suggesting admixture with North American wolves or perhaps a second domestication of canids in the Americas. Notably, initial effective population size estimates suggest at least 1000 female dogs likely existed in the Americas at the time of the first known canid burial, and that population size increased gradually over time before stabilizing roughly 1200 years before present.

Young Indigenous people, particularly those involved in the child welfare system, those entrenched in substance use and those living with HIV or hepatitis C, are dying prematurely. We report mortality rates among young Indigenous people who use drugs in British Columbia and explore predictors of mortality over time.

Indigenous young people are currently highly overrepresented in the HIV epidemic in Canada, especially in the Prairie Provinces, such as Manitoba. Understanding HIV-vulnerability in Indigenous peoples must begin with understanding that social determinants are intersectional and linked to the historical legacy of European colonization. In this paper findings that detail the influence of the intersectional social determinants on Indigenous people who become infected with HIV in their youth are presented.

Lowland South America has long been a battle-ground between European colonization and indigenous survival. Initial waves of European colonization brought disease epidemics, slavery, and violence that had catastrophic impacts on indigenous cultures. In this paper we focus on the demography of 238 surviving populations in Brazil. We use longitudinal censuses from all known indigenous Brazilian societies to quantify three demographic metrics: 1) effects of European contact on indigenous populations; 2) empirical estimates of minimum viable population sizes; and 3) estimates of post-contact population growth rates. We use this information to conduct population viability analysis (PVA). Our results show that all surviving populations suffered extensive mortality during, and shortly after, contact. However, most surviving populations exhibit positive growth rates within the first decade post-contact. Our findings paint a positive demographic outlook for these indigenous populations, though long-term survival remains subject to powerful externalities, including politics, economics, and the pervasive illegal exploitation of indigenous lands.

BACKGROUND: Although case studies indicate that indigenous peoples in Brazil often suffer from higher morbidity and mortality rates than the national population, they were not included systematically in any previous national health survey. Reported here for the first time, the First National Survey of Indigenous People’s Health and Nutrition in Brazil was conducted in 2008–2009 to obtain baseline information based on a nationwide representative sample. This paper presents the study’s rationale, design and methods, and selected results. METHODS: The survey sought to characterize nutritional status and other health measures in indigenous children less than 5 years of age and indigenous women from 14 to 49 years of age on the basis of a survey employing a representative probabilistic sample of the indigenous population residing in villages in Brazil, according to four major regions (North, Northeast, Central-West, and South/Southeast). Interviews, clinical measurements, and secondary data collection in the field addressed the major topics: nutritional status, prevalence of hypertension and diabetes mellitus in women, child hospitalization, prevalence of tuberculosis and malaria in women, access to health services and programs, and characteristics of the domestic economy and diet. RESULTS: The study obtained data for 113 villages (91.9% of the planned sample), 5,305 households (93.5%), 6,692 women (101.3%), and 6,128 children (93.1%). Multiple household variables followed a pattern of greater economic autonomy and lower socioeconomic status in the North as compared to other regions. For non-pregnant women, elevated prevalence rates were encountered for overweight (30.3%), obesity (15.8%), anemia (32.7%), and hypertension (13.2%). Among children, elevated prevalence rates were observed for height-for-age deficit (25.7%), anemia (51.2%), hospitalizations during the prior 12 months (19.3%), and diarrhea during the prior week (23.6%). CONCLUSIONS: The clinical-epidemiological parameters evaluated for indigenous women point to the accentuated occurrence of nutrition transition in all regions of Brazil. Many outcomes also reflected a pattern whereby indigenous women’s and children’s health indicators were worse than those documented for the national Brazilian population, with important regional variations. Observed disparities in health indicators underscore that basic healthcare and sanitation services are not yet as widely available in Brazil’s indigenous communities as they are in the rest of the country.

We test the hypothesis that prehistoric Native American land use influenced the Euro-American settlement process in a South Carolina Piedmont landscape. Long term ecological studies demonstrate that land use legacies influence processes and trajectories in complex, coupled social and ecological systems. Native American land use likely altered the ecological and evolutionary feedback and trajectories of many North American landscapes. Yet, considerable debate revolves around the scale and extent of land use legacies of prehistoric Native Americans. At the core of this debate is the question of whether or not European colonists settled a mostly “wild” landscape or an already “humanized” landscape. We use statistical event analysis to model the effects of prehistoric Native American settlement on the rate of Colonial land grants (1749-1775). Our results reveal how abandoned Native American settlements were among the first areas claimed and homesteaded by Euro-Americans. We suggest that prehistoric land use legacies served as key focal nodes in the Colonial era settlement process. As a consequence, localized prehistoric land use legacies likely helped structure the long term, landscape- to regional-level ecological inheritances that resulted from Euro-American settlement.

A new study of ancient mitochondrial DNA from Newfoundland and Labrador indicates that this region at the northeastern margin of North America was populated three times in succession by different indigenous groups. This research helps shed light on the movement of populations across the continent, following the initial peopling of the Americas.

To determine and compare the incidence of cancer among the 8 Arctic States and their northern regions, with special focus on 3 cross-national indigenous groups - Inuit, Athabaskan Indians and Sami.