Hunter-gatherer Populations Research Articles

Dietary reconstruction of the El Sidrón Neandertal familial group (Spain) in the context of other Neandertal and modern hunter-gatherer groups. A molar microwear texture analysis

Here, we present the analysis of occlusal molar microwear textures of eight individuals from the El Sidrón Neandertal group (Spain). The aims of the study were: 1) to document potential age-, sex-, and maternal lineage-related differences in diet within a Neandertal familial group, and 2) to place the diet of El Sidrón individuals in the context of those of other Neandertal groups. This study also offers an interpretation of the diet of the El Sidrón Neandertals by comparing their microwear signatures to those of recent hunter-gatherer populations with diverse but known diets. The intra-group examination of the microwear signatures are consistent with the females of the El Sidrón group having had more abrasive diets or having used their teeth in more para-masticatory activities than did the males. Aside from the potential sex-related differences in diet, no additional intra-group dietary separation, such as by age group or maternal lineage, was observed. In comparison to other Neandertals, El Sidrón individuals, as a group, have microwear signatures most similar to those of other Neandertals from wooded habitats and different from those that lived in more open habitats. This result is expected based on the available paleoenvironmental reconstructions from El Sidrón Cave. The diet of the El Sidrón Neandertals, just like their Neandertal counterparts from similar wooded habitats, is interpreted as having been mixed, consisting of both meat and vegetable foods.

Hunter-gatherer males are more risk-seeking than females, even in late childhood

Abstract Observed economic and labor disparities between the sexes may, in part, result from evolved sex differences in risk preferences. Using incentivized economic games, we report on sex differences in risk preferences in the Hadza, a population of hunter-gatherers. One game played in 2010 (n=233) found that more Hadza males than females prefer to gamble for a chance to earn more maize rather than settle for a sure, but smaller, amount. Similarly, a second game played in 2013 (n=102) found that male Hadza gamble a greater proportion of honey for a chance to earn more compared to female Hadza. Effect sizes are small to medium. We find weak evidence that risk-taking increases in men as their mating opportunities increase. In both games, the sex difference widens throughout childhood and is greatest among adolescents; though note that child samples are small. We explore developmental trends further using observational data on food returns in children (n=357). Our data suggest that while the mean number of calories boys bring to camp remains stable with age, the variance in their caloric returns increases. Among girls, the variance remains stable with increased age. Both the economic games and food return data are consistent with the sexual division of labor wherein boys, beginning in late childhood, begin to target riskier foods. To the extent that the Hadza allow us to make inferences about long-standing patterns of human behavior, we suggest that sex differences in risk preferences may have been present long before agriculture and the modern work environment.

Modeling Human Population Separation History Using Physically Phased Genomes.

Phased haplotype sequences are a key component in many population genetic analyses since variation in haplotypes reflects the action of recombination, selection, and changes in population size. In humans, haplotypes are typically estimated from unphased sequence or genotyping data using statistical models applied to large reference panels. To assess the importance of correct haplotype phase on population history inference, we performed fosmid pool sequencing and resolved phased haplotypes of five individuals from diverse African populations (including Yoruba, Esan, Gambia, Maasai, and Mende). We physically phased 98% of heterozygous SNPs into haplotype-resolved blocks, obtaining a block N50 of 1 Mbp. We combined these data with additional phased genomes from San, Mbuti, Gujarati, and Centre de'Etude du Polymorphism Humain European populations and analyzed population size and separation history using the pairwise sequentially Markovian coalescent and multiple sequentially Markovian coalescent models. We find that statistically phased haplotypes yield a more recent split-time estimation compared with experimentally phased haplotypes. To better interpret patterns of cross-population coalescence, we implemented an approximate Bayesian computation approach to estimate population split times and migration rates by fitting the distribution of coalescent times inferred between two haplotypes, one from each population, to a standard isolation-with-migration model. We inferred that the separation between hunter-gatherer populations and other populations happened ∼120-140 KYA, with gene flow continuing until 30-40 KYA; separation between west-African and out-of-African populations happened ∼70-80 KYA; while the separation between Maasai and out-of-African populations happened ∼50 KYA.

Significant Dietary Changes during Human Evolution and the Development of Cancer: From Cells in Trouble to Cells Causing Trouble

In all western societies, mortality rates from cancer are high and even increasing. In striking contrast, cancer rates are very rare and even non-existent in primitive cultures, like hunter-gatherer (HG) populations. HGs are free of disease as long as they adhere to their traditional low-insulinemic “Paleolithic” nutrition. With acculturation and transition to current high-carbohydrate/high-insulinemic “Western” diets (HCHIDs), cancer develops in high rates. This paper follows the question of how significant nutritional changes, brought about by the Agricultural revolution, may cause development of cancer. The evidence presented shows that the switch from a Paleolithic to a Western nutrition has brought about significant metabolic perturbations, like an abnormally increased activation of the insulinlike growth factor system, the sympathetic nervous system and the renin-angiotensin-system, an increased expression of HIF-1α and other more, all of which are deeply involved in cancer development through promotion of proliferation, angiogenesis, inflammation, macrophage infiltration, metastasis and inhibition of apoptosis. In addition, HCHIDs generate oxidative stress which may cause mitochondrial damage and genomic instability, and may interfere with normal stem cell development. Faulty is suggested to play a significant role in cancer development: hydrogen peroxide, generated at low concentrations, represents an important chemical mediator in the regulation of various cellular signal transduction processes, including stem cell development. Oxidative stress may be sensed by cells as signaling. Faulty redox signaling is proposed to affect normal stem cell development by sustained activation of uncoupling protein 2, leading to inhibition of differentiation (maturation arrest), sustained uncontrolled proliferation, and glycolysis with high expression of hexokinase II, typical features of cancer. In summary, an abnormal diet-related activation of various metabolic systems, together with faulty signaling, is suggested to play a pivotal role in cancer development.

From Chauvet to Lascaux: 15,000 Years of Cave Art

The earliest art of Western Europe was evolving together with the Homo sapiens population of hunter-gatherers in the glacial environment of the northern hemisphere over the entire Upper Paleolithic (36–13 ka BP). The most important rock art sites, such as Altamira and La Garma in Spain, and Lascaux, Niaux, Cussac, and Chauvet in France, are relevant to the socio-cultural behavior and needs of anatomically modern humans. In this paper, we intend to identify certain changes in the symbolic language, in the ways animals are rendered, and in the layout of artistic space over 15,000 years separating the two key rock art galleries with the best preserved representations: Chauvet (36 ka BP) and Lascaux (21 ka BP). Chauvet, discovered in 1994, is located in the Ardeche Valley near the Mediterranean coast. In this large cave, numerous new kinds of Upper Paleolithic rock art were documented, spanning two distinct occupation periods between 37,000–30,000 years ago. The early stage is the Aurignacian with black zoomorphic paintings, dating to 37,000–33,500 BP. Lascaux, discovered in 1940, is situated in the Vezere Valley, 120 km away from the Atlantic coast, among a large cluster of rupestral art sites in caves and rock shelters. Today, the cave is closed for the public because intense tourist activities over many years from its discovery until 1963 have disrupted the microclimate of the cave and endangered the paintings.

A Model-Based Analysis of the Minimum Size of Demographically-Viable Hunter-Gatherer Populations

A non-spatial agent-based model is used to explore how marriage behaviors and fertility affect the minimum population size required for hunter-gatherer systems to be demographically viable. The model incorporates representations of person- and household-level constraints and behaviors affecting marriage, reproduction, and mortality. Results suggest that, under a variety of circumstances, a stable population size of about 150 persons is demographically viable in the sense that it is largely immune from extinction through normal stochastic perturbations in mortality, fertility, and sex ratio. Less restrictive marriage rules enhance the viability of small populations by making it possible to capitalize on a greater proportion of the finite female reproductive span and compensate for random fluctuations in the balance of males and females.

New theoretical discourses in the discussion of the Neolithisation process in South Scandinavia during the late 5th and early 4th millennium BC – an identification of learning processes, communities of practise and migrations

In this paper, it is argued that agriculture is a very complex technology, which takes a long time to learn, thus making it very difficult for agrarian practises to spread as ideas. Instead, based on a detailed survey of primary agrarian evidence (direct 14C dates of cereals and domesticated animals) and secondary evidence of material culture (polished axes and pottery), it is claimed that the expansions of agrarian practises in South Scandinavia are associated with the migration of farmers who were related to the Michelsberg Culture. These incoming farmers had the appropriate skills and the ability to teach the indigenous hunter-gatherer populations about agriculture by establishing communities of practice, a fact which supports the theory of integrationism. The engagement in these communities of practise changed the identity and material culture of the immigrating farmers, as well as the indigenous hunter-gatherers, thus creating new agrarian societies in South Scandinavia which were interconnected in a regional as well as larger European network.

Niche dynamics of Palaeolithic modern humans during the settlement of the Palaearctic

AbstractAimDuring the Late Pleistocene (c. 126–10 ka), modern humans (Homo sapiens) expanded their geographical range across Eurasia and eventually colonized the Americas. Although the routes by which they migrated have been intensively analysed, the dynamics of their realized climatic niche are still largely unknown. We assess temporal changes in the climatic niche of modern humans, the geographical distribution of their climatic niche and whether niche dynamics correlate with the magnitude of climate change and cultural advances, between 46 and 11 ka.LocationPalaearctic.MethodsUsing the radiocarbon dated archaeological record and spatial palaeoclimatic simulations, we quantify different parameters of the realized climatic niche of modern humans (niche overlap, niche breadth and climatic marginality) between consecutive 1000–2000 year intervals. Moreover, using climate envelope models, we map the potential distributions of modern humans for each time interval and identify the regions that remained more climatically suitable and stable for modern humans through time.ResultsBetween 46 and 22 ka the climatic niche of modern humans expanded, including periods of intense growth in niche breadth at 40 and 30 ka. Changes in seasonal water availability and technological innovations partly correlate with dynamics in niche parameters. We document a persistent climatically suitable mid‐latitude belt in south Siberia linking western Europe to the Far East that may have facilitated human migration, and a potential climatic refugium in Beringia.Main conclusionsThe climatic niche of modern humans changed across the Late Pleistocene, as the result of both climatic and cultural changes. These populations of hunter‐gatherers occupied novel climatic conditions but also remained in previously occupied areas under changing climates during the settlement of the Palaearctic. Our approach can provide clues as to where early modern humans may have overlapped in geographical and environmental space with Neanderthals or Denisovans, as evidenced by their contribution to the genetic heritage of some current populations.

Isotopic evidence of breastfeeding and weaning practices in a hunter–gatherer population during the Late/Final Jomon period in eastern Japan

Jomon hunter–gatherers in Japan commonly show Neolithic characteristics, such as intensive utilization of potteries, grinding stones, and many plant food sources. In this study, breastfeeding and weaning practices in a Jomon hunter–gatherer population are investigated to evaluate two hypotheses concerning the relations between utilization of potteries/plant foods and early weaning and children's diet around and after the weaning process. Stable carbon and nitrogen isotope ratios were investigated for 46 subadult and 47 adult human skeletons excavated from the Yoshigo site of the Late/Final Jomon period (approximately 4000–2300 years BP) in eastern Japan. A new analytical procedure was developed and residuals of nitrogen isotope ratios were calculated to cancel out the effect of positive correlation in the carbon and nitrogen isotope ratios. Age changes in the residuals showed that the age at the end of weaning in the Yoshigo population was 3.5 years (2.3–5.5 years in 95% credible interval), which is not younger than that in typical non-industrialized populations and the other skeletal hunter–gatherer populations. Furthermore, most infants were probably weaned using a combination of the same food sources as those eaten by adults. These results suggest that the utilization of pottery and plant food per se is not a sole determinant of the age at the end of weaning in past human populations, and a special diet was not always applied during and just after the weaning process.

Spatio-temporal distribution of hunter–gatherer archaeological sites in the Hokkaido region (northern Japan): An overview

The spatio-temporal distribution of archaeological sites in the Hokkaido region reveals hunter–gatherer population dynamics from the Upper Palaeolithic (>14,000 cal. yr BP) through the Neolithic/Jomon and Epi Jomom period ( c. 14,000–1300 cal. yr BP) to the historic Ainu period ( c. 700–100 cal. yr BP). It appears that most cultural transitions coincide with periods of climate and environmental change. However, this observation does not automatically mean causality and, therefore, other potential driving factors must be checked. The data support the hypothesis that Palaeolithic subsistence was (at least partly) based on terrestrial hunting. Paralleled by lateglacial climate amelioration, rising sea levels and a change in marine currents, this strategy shifted towards marine resources and plant exploitation at the beginning of the Jomon period. Along with continuous Holocene climate warming, Hokkaido’s Neolithic Jomon population increased culminating in the Middle Jomon period (5000–4000 cal. yr BP). Simultaneously, Jomon subsistence underwent a process of diversification and intensification in exploitation of food resources. This practice probably allowed the persistence of the Middle Jomon culture beyond the Holocene temperature optimum (around 5000 cal. yr BP). Thereafter, the population decreased until the end of the Jomon culture accompanied by a trend towards cooler climate conditions and a shift in subsistence towards a more narrow range of food resources with increased hunting and less plant food. Population re-increased during the Satsumon/Okhotsk culture periods (1500–700 cal. yr BP), which may be the result of Okhotsk immigration because of climate cooling in the regions north of Hokkaido and enhanced inner-Hokkaido trade (between Satsumon and Okhotsk) and trade with communities outside Hokkaido. During the Ainu period ( c. 700–100 cal. yr BP), site, and possibly population numbers, re-decreased significantly and concentrated in eastern Hokkaido. Whether social and/or climatic factors brought about the Satsumon–Ainu cultural transition and the observed change in population pattern remains unresolved.

The Rosa-Keystone Dunes Field: The geoarchaeology and paleoecology of a late Quaternary stabilized dune field in Eastern Beringia

Stabilized sand sheets and dunes hold a remarkable amount of information on paleoenvironmental conditions under which late Quaternary landscapes evolved in northern subarctic regions. We provide the results of a project focused on understanding the development of lowland environments and ecosystems, including dunes and sand sheets, which were critical habitat for early human occupations in subarctic regions. Our study area is the Rosa-Keystone Dunes Field in the Shaw Creek Flats of the middle Tanana River basin, interior Alaska, one of the oldest continuously occupied areas in North America (14,000 cal. BP to present). The disturbance regimes of reactivated dunes and associated forest fire cycles between 12,500 and 8800 cal. BP fostered a unique early to mid-successional mixed vegetation community including herbaceous tundra, shrubs, and deciduous trees. This environment provided key habitats for large grazers and browsers, significant resources for early hunter-gatherer populations in central Alaska. After 8000 cal. BP, the expansion of black spruce and peatlands heightened landscape stability but decreased the range of local habitat for large grazers. Hunter-gatherer economic change during these periods is consistent with human responses to local and regional landscape disturbance and restructuring.

Neandertals revised

The last decade has seen a significant growth of our knowledge of the Neandertals, a population of Pleistocene hunter-gatherers who lived in (western) Eurasia between ∼400,000 and 40,000 y ago. Starting from a source population deep in the Middle Pleistocene, the hundreds of thousands of years of relative separation between African and Eurasian groups led to the emergence of different phenotypes in Late Pleistocene Europe and Africa. Both recently obtained genetic evidence and archeological data show that the biological and cultural gaps between these populations were probably smaller than previously thought. These data, reviewed here, falsify inferences to the effect that, compared with their near-modern contemporaries in Africa, Neandertals were outliers in terms of behavioral complexity. It is only around 40,000 y ago, tens of thousands of years after anatomically modern humans first left Africa and thousands of years after documented interbreeding between modern humans, Neandertals and Denisovans, that we see major changes in the archeological record, from western Eurasia to Southeast Asia, e.g., the emergence of representational imagery and the colonization of arctic areas and of greater Australia (Sahul).

Pyrodiversity and the anthropocene: the role of fire in the broad spectrum revolution.

The Anthropocene colloquially refers to a global regime of human-caused environmental modification of earth systems associated with profound changes in patterns of human mobility, as well as settlement and resource use compared with prior eras. Some have argued that the processes generating the Anthropocene are mainly associated with population growth and technological innovation, and thus began only in the late Holocene under conditions of dense sedentism and industrial agriculture.(1) However, it now seems clear that the roots of the Anthropocene lie in complex processes of intensification that significantly predate transitions to agriculture.(2,3) What intensification is remains less clear. For some it is increasing economic productivity that increases carrying capacity, the drivers of which may be too diverse and too local to generalize.(4,5) For others using Boserup's ideas about agrarian intensification, increasing density in hunter-gatherer populations can produce declines in subsistence efficiency that increase incentives for investing labor to boost yield per unit area, which then elevates Malthusian limits on carrying capacity.(6-8) As Morgan(9) demonstrates in a comprehensive review, the legacy of such Boserupian intensification is alive, well, and controversial in hunter-gatherer archeology. This is a result of its potential for illuminating processes involved in transformations of forager socio-political and economic systems, including those dominated by harvesting more immediate-return resources and high residential mobility as well as those characterized by more delayed-return material economies with reduced residential mobility, a broader spectrum of resources, degrees of storage, and greater social stratification. Here we detail hypotheses about the processes involved in such transitions and explore the way that anthropogenic disturbance of ecosystems, especially the use of landscape fire, could be fundamentally entangled with many broad-spectrum revolutions associated with intensified foraging systems.

A Biocultural Investigation of Gender Differences in Tobacco Use in an Egalitarian Hunter-Gatherer Population.

In the developing world, the dramatic male bias in tobacco use is usually ascribed to pronounced gender disparities in social, political, or economic power. This bias might also reflect under-reporting by woman and/or over-reporting by men. To test the role of gender inequality on gender differences in tobacco use we investigated tobacco use among the Aka, a Congo Basin foraging population noted for its exceptionally high degree of gender equality. We also tested a sexual selection hypothesis-that Aka men's tobacco use is related to risk taking. Tobacco use, income, tobacco purchases, tobacco sharing, reasons for using tobacco, risk taking, and other variables were measured using structured surveys and peer reports. Tobacco use was verified by testing for salivary cotinine, a nicotine metabolite. Contrary to expectations, we found a very large male bias in tobacco use. Low levels of use among females appeared to be explained by aversions to tobacco, concerns over its negative effects on fetal health, and a desire to attract husbands, who prefer nonsmoking wives. High male use appeared to be related to a desire to enhance hunting abilities and attract and/or retain wives, who prefer husbands that smoke. We conclude that low levels of smoking by Aka women are better explained by the hypothesis that women evolved to avoid plant toxins to protect their fetuses and nursing infants. High male use might be better explained by sexual selection. We also highlight the important role that recreational drugs appear to play in hunter-gatherer sharing relationships.

Sophisticated sleep improves our brains: Our advanced cognitive and social skills might derive from the evolution of improved sleep quality; today, sleep therapy could help with mental health issues and learning.

In the past decades, sleep researchers have been quietly accumulating knowledge about the physiology of sleep. Without any real health application for this knowledge, however, the public and the press have slept blissfully through most of their breakthroughs. Yet, recent findings about the evolution of sleep in humans and the effects of sleep disruption on human health seem to have finally woken the public up. A recent paper from David Samson and Charles Nunn, evolutionary anthropologists from Duke University in the USA, puts forward the hypothesis that humans have evolved more efficient sleep patterns than other primates and that this is because “[e]arly humans experienced selective pressure to fulfill sleep needs in the shortest time possible” [1]. This efficient slumber, the authors argue, might have contributed to setting our ancestors on the evolutionary path toward human civilization. The New York Times , among other newspapers, covered the publication, which follows in the wake of research indicating that human sleep patterns have stayed largely stable during the course of human evolution, from hunter‐gatherers to modern city dwellers [2]. Both of these insights provide evolutionary context for the health impact of too little sleep, with both epidemiological and clinical research showing that sleep disruption has a negative effect on health and well‐being. More recently, however, there is evidence that sleep has distinctly positive therapeutic potential to treat a variety of phobias and other psychotic conditions. The evolutionary study that attracted media attention raises interesting questions about the co‐evolution of sleep and human cognitive faculties. Samson and Nunn suggest that sleep became subject to strong selective pressures—“including increased predation risk […] threats from intergroup conflict, and benefits arising from increased social interaction” [1]—when our ancestors moved down from the trees and onto the savannah. As a result, …

Big Hole (41TV2161): Two Stratigraphically Isolated Middle Holocene Components in Travis County, Texas Volume I

Big Hole (41TV2161): Two Stratigraphically Isolated Middle Holocene Components in Travis County, Texas Volume I

Aproximación al estudio arqueopetrológico de la industria lítica procedente del abrigo de La Roureda (Vilafranca, Els Ports, Castelló, País Valencià) [Archaeopetrological study of the lithic industry from “La Roureda” rockshelter

Archaeopetrological study of the lithic industry from “La Roureda” rockshelter (Vilafranca, Els Ports, Castellon, Valencian Country) Roureda’s (La Roureda) rockshelter is an Epimagdalenian site located in Vilafranca (northern Valencian Country) in the east of the Iberian Peninsula. The site was discovered by Dr. F. Arasa in the late 1970s. More recently, two vertical trenches were dug at this site to determine the sequence of occupations over time: a 2 m 2 trench on the rock shelter floor and a 1 m 2 trench on the eroded area under the platform. The excavation of the 2 m 2 in the rock shelter outlined an Early Epimagdalenian level dated to 11350 ± 50 BP (13373-13122 cal. BP). One of the main features in this site is the abundant lithic industry recovered (4639 pieces), all of it made exclusively from chert. In recent years, the typology and technology of these materials has been studied but this is the first archaeopetrological study, not only for this site but for this region of Iberia. Among the stone tools, backed bladelets are the most significant typological group, followed by the truncated bladelets and the group of notched-denticulates. End-scrapers and pieces with retouched edges are also important. The remaining groups represent less than 3%. The archaeopetrological study has been divided into two parts. Firstly, a macroscopic approach (petrographic and micropalaeontologic) was developed for all the retouched tools (286), the production blanks (2459) and cores (20). It should be note that during the excavations, 4639 elements were recovered, but about 45% of these being debris. Secondly, geological surveys were developed, which allowed for the identification of several outcrops with cherts within a 100 km area around the site. Several samples of those cherts were microscopically compared to some of the archaeological lithic samples. The results of these analyses allow for the identification of the presence of 4 different varieties of chert, with a primarily brackish or lacustrine origin. Two of them (Types A & B) corresponding to a palustrine environment formation, one (Type D) related to a marine environment formation, and finally, one (Type C) being undefined. Two of these varieties, the most abundant in the site (Types A and B) may be related to several outcrops located both in a local and regional distance. Meanwhile, Types C and D are much less abundant. The nearest varieties of chert to the site (Types A & B), which are of high quality for knapping and relatively homogenous, were the most common in the Epimagdalenian level. These types showed all stages of the “Chaine Operatoire Lithique” (C.O.L.) within the site. Nevertheless, a distinction can be observed between them. While Type A was used mainly for projectiles and in a lesser way for domestic tools, Type B was mainly used in the opposite way (mainly having been used for domestic tools). The explanation will likely be related to the homogeneity of their textural differences. On the other hand, neither Type C nor Type D showed the complete sequence of the C.O.L. The first was probably introduced into the site mainly as knapped blades or bladelets, while Type D, the lowest in quality, was mainly used for domestic purposes. It was not possible to locate the outcrop of type C. Nevertheless, the outcrops of Type D are relatively abundant and in spite of its quality for knapping, this chert was frequently used. Outcrops of this type of chert can be found throughout the region. The aim of this project in the near future is to enlarge this study to other Upper Palaeolithic and Mesolithic sites and develop a deeper knowledge of the siliceous outcrops used by hunter-gatherer populations in this region. This is a project of great relevance, not only for understanding the economy of raw materials at the Roureda rockshelter, but also for knowing the possibilities of chert trade in northern Valencian Country.

Resilience in prehistoric persistent hunter–gatherers in northwest Kyushu, Japan as assessed by population health and archaeological evidence

Resilience theory provides a critical framework for examining the capacity of human societies to respond to changes to essential features of the human–environment relationship. Studies employing the long-term perspective required to understand adaptive cycles of resilience are still rare. Despite the challenges of working with variably preserved materials and small sample sizes, archaeological remains provide access to longitudinal data. One way of approaching human resilience is through its impacts on human well-being, which is often measured via population health. Population health is typically described by child mortality and morbidity rates. Here, we argue that the specific use of permanent biological markers of developmental stress (fluctuating dental asymmetry and dental enamel hypoplasia) serve as a proxy for prehistoric population health. A case study from Japan is used to test this proposal. We focus on persistent hunter–gatherer populations before and after the introduction of agriculture to the region. Too frequently the focus of research in periods of agricultural transition favors those populations making the transition to agriculture, dismissing persistent hunter–gatherers as on the ecological margins. Archaeological data from prehistoric NW Kyushu indicate the persistence of a culturally autonomous hunter–gatherer Jōmon population for several centuries into the agricultural Yayoi period. Did these populations suffer from a decline in population health as might be expected if they were, in fact, reduced to the margins of the social-ecological system? Using dental markers of developmental stress from six persistent hunter–gatherer sites in NW Kyushu, we tested the hypothesis that hunter–gatherer developmental stress loads did not change over time. There were no statistically significant differences in developmental stress between pre-agricultural hunter–gatherers and persistent hunter–gatherer during the agricultural period. We interpret the results as evidence of resilience of these persistent hunter–gatherers in spite of major disruptions from immigrant agricultural populations to the social and ecological environments of NW Kyushu. Developmental stress in an archaeological context may serve as a useful proxy of resilience of past populations and future studies might take additional indicators of health into consideration.

BaAka women's health and subsistence practices in transitional conservation economies: Variation with age, household size, and food security.

Using ethnographic interviews and biological measures, this article investigates changing health and nutrition of a hunter-gatherer population transitioning from a forest-based subsistence system to a horticultural and market-driven lifestyle. This study represents biological and dietary recall data for adult female foragers (18+; n = 60) across two villages, Mossapoula (MS) and Yandoumbé (YDBE), in the Dzanga Sangha Protected Areas (APDS), Central African Republic (CAR). Standard anthropometric measurements (height, weight, skinfolds) and hemoglobin values were collected to assess short-term nutritional status. BMI was similar across all three age classes in YDBE, but differed amongst women of MS (ANOVA; F = 6.34, df = 30, P = 0.005).Values were lowest among the older women in older age class 3 who also had the greatest number of dependents. Overall SS values were significantly negatively correlated with the number of biological children (r = -0.33, P = 0.01) in both villages. Here, we identify older BaAka women, caring for their own children and grandchildren, as particularly vulnerable to economic changes and food insecurity. We found older women, especially those in a community with greater restrictions on access to forest resources to have more dependents, reduced market integration, and low BMI relative to younger women in the population. Am. J. Hum. Biol. 28:453-460, 2016. © 2015 Wiley Periodicals, Inc.

Lithic networks reveal early regionalization in late Pleistocene North America

North America was colonized by hunter–gatherer populations during the late Pleistocene, and the Clovis culture is the earliest well-documented evidence of this event. Long-standing questions about the colonization process persist, including the extent to which low-density populations maintained contact across the continent and if foraging territories overlapped or were spatially-discrete. Here, we use a network approach to examine the spatial structure of land use associated with the earliest hunter–gatherer populations in North America. In particular, we examine the co-occurrence of raw materials used for stone tool manufacture at archaeological sites across the continent. Using a database of 84 Clovis assemblages we show that there are three large isolated, mostly spatially-discrete, lithic exploitation networks across the continent. These regions closely correspond to previously identified differences in Clovis point form, suggesting that Clovis populations were becoming regionally distinct. This process of cultural diversification that begins in the late Pleistocene, continues to develop into the Holocene.