The ecological and evolutionary energetics of hunter‐gatherer residential mobility

Residential mobility is a key aspect of hunter‐gatherer foraging economies and therefore is an issue of central importance in hunter‐gatherer studies. 1 - 7 Hunter‐gatherers vary widely in annual rates of residential mobility. Understanding the sources of this variation has long been of interest to anthropologists and archeologists. The vast majority of hunter‐gatherers who are dependent on terrestrial plants and animals move camp multiple times a year because local foraging patches become depleted and food, material, and social resources are heterogeneously distributed through time and space. In some environments, particularly along coasts, where resources are abundant and predictable, hunter‐gatherers often become effectively sedentary. But even in these special cases, a central question is how these societies have maintained viable foraging economies while reducing residential mobility to near zero.     

A Burning Issue: Rethinking the Transition from Hunter‐Gatherer to Industrial Sociometabolic Regimes

Hunter‐gatherers are commonly seen as having a fundamentally different sociometabolic regime from agrarian and industrial societies because they are thought to directly appropriate the products of natural ecosystems without modifying those systems in order to enhance their productivity. However, ethnographic and archeological evidence reveals that many hunter‐gatherers extensively employed fire to manage their ecosystems so as to increase production of desirable wild resources, thus engaging in “colonization of nature” that is not qualitatively different from that practiced by other types of society. They systematically burned wild vegetation in order to increase populations of edible wild plants consumed by humans and promote growth of forage for game animals. Deliberate ecosystem burning by Australian Aborigines represented an energy expenditure of 1,512 gigajoules per capita per year (GJ/capita/yr), a level of energy use that is more than three times higher than the United States (445 GJ/capita/yr). It is their profligate consumption of biomass energy that explains why the quality of life of many hunter‐gatherers was often better than that of traditional settled peasant farmers. Hence, the extent to which hunter‐gatherers have a distinct type of sociometabiolic regime is called into question. It can be argued that in the course of social evolution, there have been only two sociometabolic regimes. In one type, which includes hunter‐gatherers, swidden agriculturalists, and industrial societies, extrasomatic energy does most of the productive work, whereas in the other type, that of premodern settled agriculturalists, production is largely dependent on human muscle power.     

Oral microbiomes from hunter‐gatherers and traditional farmers reveal shifts in commensal balance and pathogen load linked to diet

Maladaptation to modern diets has been implicated in several chronic disorders. Given the higher prevalence of disease such as dental caries and chronic gum diseases in industrialized societies, we sought to investigate the impact of different subsistence strategies on oral health and physiology, as documented by the oral microbiome. To control for confounding variables such as environment and host genetics, we sampled saliva from three pairs of populations of hunter‐gatherers and traditional farmers living in close proximity in the Philippines. Deep shotgun sequencing of salivary DNA generated high‐coverage microbiomes along with human genomes. Comparing these microbiomes with publicly available data from individuals living on a Western diet revealed that abundance ratios of core species were significantly correlated with subsistence strategy, with hunter‐gatherers and Westerners occupying either end of a gradient of Neisseria against Haemophilus, and traditional farmers falling in between. Species found preferentially in hunter‐gatherers included microbes often considered as oral pathogens, despite their hosts' apparent good oral health. Discriminant analysis of gene functions revealed vitamin B5 autotrophy and urease‐mediated pH regulation as candidate adaptations of the microbiome to the hunter‐gatherer and Western diets, respectively. These results suggest that major transitions in diet selected for different communities of commensals and likely played a role in the emergence of modern oral pathogens.     

Sex, Status, and Authority in Egalitarian Society

Disagreement exists concerning the nature of relations between the sexes in foraging societies. The crucial issue concerns the quality of interactions across rather than within sexual boundaries. Approaching the problem in terms of a political analysis allows cross-cultural comparisons utilizing behavioral data. While all foraging societies are egalitarian within sexual boundaries, not all are egalitarian across sexual boundaries. The analytic usefulness of two subtypes of egalitarian society, the "pure-egalitarian" and the "semi-egalitarian," is suggested . [sexual politics, egalitarian societies, status of women, hunters and gatherers]     

A multilevel analytical framework for studying cultural evolution in prehistoric hunter–gatherer societies

Over the past decade, a major debate has taken place on the underpinnings of cultural changes in human societies. A growing array of evidence in behavioural and evolutionary biology has revealed that social connectivity among populations and within them affects, and is affected by, culture. Yet the interplay between prehistoric hunter–gatherer social structure and cultural transmission has typically been overlooked. Interestingly, the archaeological record contains large data sets, allowing us to track cultural changes over thousands of years: they thus offer a unique opportunity to shed light on long‐term cultural transmission processes. In this review, we demonstrate how well‐developed methods for social structure analysis can increase our understanding of the selective pressures underlying cumulative culture. We propose a multilevel analytical framework that considers finer aspects of the complex social structure in which regional groups of prehistoric hunter–gatherers were embedded. We put forward predictions of cultural transmission based on local‐ and global‐level network metrics of small‐scale societies and their potential effects on cumulative culture. By bridging the gaps between network science, palaeodemography and cultural evolution, we draw attention to the use of the archaeological record to depict patterns of social interactions and transmission variability. We argue that this new framework will contribute to improving our understanding of social interaction patterns, as well as the contexts in which cultural changes occur. Ultimately, this may provide insights into the evolution of human behaviour.     

Hunter‐gatherer mobility and embedded raw‐material procurement strategies in the mediterranean upper paleolithic

Since the early 1980s, the sourcing of lithic raw materials has become central to studies of the territorial range and mobility strategies of Pleistocene foraging societies. Results have been fruitful but somehow repetitive. We will discuss the embedded procurement strategy, which presumes that raw material acquisition was part of other subsistence activities rather than an autonomous technological task. We argue that this theoretical assumption, when taken as dogma, restricts the role of technology in human history and also underestimates the way some lithic resources may have affected the organization of past hunter‐gatherers. We base our discussion on the Upper Paleolithic (UP) from the Liguro‐Provençal arc, with examples from the Proto‐Aurignacian and the Epigravettian. Our regional record shows that in this context the movement of rocks over distances greater than 100 km was the norm rather than the exception. We argue that these long‐distance procurements mirror technical needs that were oriented toward the selection of high‐quality flints. We support the hypothesis that indirect procurement was an important component of regional socio‐economic networks.     

Ecological determinants of women's status among hunter/gatherers

Women's status in preindustrial communities has been the focus of a number of studies in the past two decades. However, very few of these studies deal exclusively with hunter/gatherers, and none of the hunter/gatherer studies combine empirical tests with explanations. Because of a number of differences with settled agricultural villagers, hunter/gatherers can be viewed as the focus of distinctive substantive ecological theory. A cross-cultural materialist approach to the problem of why women's status is high among some hunter/gatherers and low among others indicates that several factors are strongly related to differences in women's status. Frequent and severe resource stress is the most strongly associated with low female status in the domestic and political domain, while warfare exerts an independent but lesser effect. The importance of hunting constitutes a third and still more weakly associated variable. Thus, women's political and domestic status among hunter/gatherers predominantly appears to have resulted from techno-ecological conditions. In contrast, technoecological conditions appear to have had no strong influence on women's status in ritual roles, including shamanism. Several possible ways that women's status might be linked to techno-economic conditions are proposed. The results of this study demonstrate that Leacock's assumptions of systematic bias in the ethnographic record, and of ubiquitous female equality among band level societies are unjustified.     

Sex‐biased dispersal of human ancestors

Some anthropologists and primatologists have argued that, judging by extant chimpanzees and humans, which are female‐biased dispersers, the common ancestors of humans and chimpanzees were also female‐biased dispersers. It has been thought that sex‐biased dispersal patterns have been genetically transmitted for millions of years. However, this character has changed many times with changes in environment and life‐form during human evolution and historical times. I examined life‐form and social organization of nonhuman primates, among them gatherers (foragers), hunter‐gatherers, agriculturalists, industrialists, and modern and extant humans. I conclude that dispersal patterns changed in response to environmental conditions during primate and human evolution.     

Mammouth et comportements de subsistance à l’Épigravettien : analyse archéozoologique du secteur de la fosse no 7 associée à l’habitation no 1 de Mezhyrich (Ukraine)

Zooarchaeological analyses were carried on new large mammal bone materials, from the Epigravettian (Late Upper Palaeolithic) site Mezhyrich (Ukraine), in the pit n^o 7 area associated with the mammoth bone dwelling n^o 1. The results exhibit a usage of the pit as a dump area of food and technical remains from mainly mammoth, hare and fox processing, and bone fuels. The information about mammoth procurement by the last Palaeolithic hunter–gatherers in Eastern Europe allows to document the hunting activities on the mammoth populations, which were probably already weakened at the end of the Pleistocene.     

The emergence and intensification of early hunter‐gatherer niche construction

Hunter‐gatherers, especially Pleistocene examples, are not well‐represented in archeological studies of niche construction. However, as the role of humans in shaping environments over long time scales becomes increasingly apparent, it is critical to develop archeological proxies and testable hypotheses about early hunter‐gatherer impacts. Modern foragers engage in niche constructive behaviors aimed at maintaining or increasing the productivity of their environments, and these may have had significant ecological consequences over later human evolution. In some cases, they may also represent behaviors unique to modern Homo sapiens. Archeological and paleoenvironmental data show that African hunter‐gatherers were niche constructors in diverse environments, which have legacies in how ecosystems function today. These can be conceptualized as behaviorally mediated trophic cascades, and tested using archeological and paleoenvironmental proxies. Thus, large‐scale niche construction behavior is possible to identify at deeper time scales, and may be key to understanding the emergence of modern humans.     

Means,variances, and ranges in reproductive success: comparative evidence

Data on reproductive success in traditional cultures suggest that for men, but not for women, range and variance rise as subsistence intensifies. For hunter–gatherers, ranges and variances tend to cluster in single digits: they reach 15 or 16, at the high end. For herder-gardeners, ranges and variances are more consistently in double digits: they get as high as 80 or 85. And for full-time agriculturalists in the first civilizations, ranges consistently ran to triple digits: emperors from Mesopotamia to Peru were the fathers of hundreds of children. In human societies, as in other animal societies, reproductive skew goes up with a more sedentary life.     

Proving communal warfare among hunter‐gatherers: The quasi‐rousseauan error

Was human fighting always there, as old as our species? Or is it a late cultural invention, emerging after the transition to agriculture and the rise of the state, which began, respectively, only around ten thousand and five thousand years ago? Viewed against the life span of our species, Homo sapiens, stretching back 150,000–200,000 years, let alone the roughly two million years of our genus Homo, this is the tip of the iceberg. We now have a temporal frame and plenty of empirical evidence for the “state of nature” that Thomas Hobbes and Jean‐Jacque Rousseau discussed in the abstract and described in diametrically opposed terms. All human populations during the Pleistocene, until about 12,000 years ago, were hunter‐gatherers, or foragers, of the simple, mobile sort that lacked accumulated resources. Studying such human populations that survived until recently or still survive in remote corners of the world, anthropology should have been uniquely positioned to answer the question of aboriginal human fighting or lack thereof. Yet access to, and the interpretation of, that information has been intrinsically problematic. The main problem has been the “contact paradox.” Prestate societies have no written records of their own. Therefore, documenting them requires contact with literate state societies that necessarily affects the former and potentially changes their behavior, including fighting.     

Hmong infrapolitics: a view from Vietnam

Drawing upon notions of indigenization of modernity, agency and resistance in the context of an egalitarian society – the Hmong in northern Vietnam – I explore whether agency that is directed at diverting modernization is automatically intentional and patent, whether under certain circumstances it becomes resistance, and whether it is necessarily a project. I suggest the Hmong in Vietnam use infrapolitics while being tactically selective about modernity. I note that agency and the power to act appear and evolve in context and must be studied in relation to the specific circumstances that have formed the acting subjects. My argument relates to Sahlins’ proposition that ‘Local societies everywhere have attempted to organise the irresistible forces of Western World system by something even more inclusive – their own system of the world, their own culture.’     

Hunter‐gatherers and human evolution

Although few hunter‐gatherers or foragers exist today, they are well documented in the ethnographic record. Anthropologists have been eager to study them since they assumed foragers represented a lifestyle that existed everywhere before 10,000 years ago and characterized our ancestors into some ill‐defined but remote past. In the past few decades, that assumption has been challenged on several grounds. Ethnographically described foragers may be a biased sample that only continued to exist because they occupied marginal habitats less coveted by agricultural people. 3 In addition, many foragers have been greatly influenced by their association with more powerful agricultural societies. 4 It has even been suggested that Holocene foragers represent a new niche that appeared only with the climatic changes and faunal depletion at the end of the last major glaciation. 5 Despite these issues, the ethnographic record of foragers provides the only direct observations of human behavior in the absence of agriculture, and as such is invaluable for testing hypotheses about human behavioral evolution. 6 .     

Prevention,diagnosis and treatment of high‐throughput sequencing data pathologies

High‐throughput sequencing (HTS) technologies generate millions of sequence reads from DNA/RNA molecules rapidly and cost‐effectively, enabling single investigator laboratories to address a variety of ‘omics’ questions in nonmodel organisms, fundamentally changing the way genomic approaches are used to advance biological research. One major challenge posed by HTS is the complexity and difficulty of data quality control (QC). While QC issues associated with sample isolation, library preparation and sequencing are well known and protocols for their handling are widely available, the QC of the actual sequence reads generated by HTS is often overlooked. HTS‐generated sequence reads can contain various errors, biases and artefacts whose identification and amelioration can greatly impact subsequent data analysis. However, a systematic survey on QC procedures for HTS data is still lacking. In this review, we begin by presenting standard ‘health check‐up’ QC procedures recommended for HTS data sets and establishing what ‘healthy’ HTS data look like. We next proceed by classifying errors, biases and artefacts present in HTS data into three major types of ‘pathologies’, discussing their causes and symptoms and illustrating with examples their diagnosis and impact on downstream analyses. We conclude this review by offering examples of successful ‘treatment’ protocols and recommendations on standard practices and treatment options. Notwithstanding the speed with which HTS technologies – and consequently their pathologies – change, we argue that careful QC of HTS data is an important – yet often neglected – aspect of their application in molecular ecology, and lay the groundwork for developing a HTS data QC ‘best practices’ guide.     

Population genetic insights into the social organization of Guinea baboons (Papio papio): Evidence for female‐biased dispersal

Sex differences in philopatry and dispersal have important consequences on the genetic structure of populations, social groups, and social relationships within groups. Among mammals, male dispersal and female philopatry are most common and closely related taxa typically exhibit similar dispersal patterns. However, among four well‐studied species of baboons, only hamadryas baboons exhibit female dispersal, thus differing from their congenerics, which show female philopatry and close‐knit female social relationships. Until recently, knowledge of the Guinea baboon social system and dispersal pattern remained sparse. Previous observations suggested that the high degree of tolerance observed among male Guinea baboons could be due to kinship. This led us to hypothesize that this species exhibits male philopatry and female dispersal, conforming to the hamadryas pattern. We genotyped 165 individuals from five localities in the Niokolo‐Koba National Park, Senegal, at 14 autosomal microsatellite loci and sequenced a fragment of the mitochondrial hypervariable region I (HVRI) of 55 individuals. We found evidence for higher population structuring in males than in females, as expected if males are the more philopatric sex. A comparison of relatedness between male–male and female–female dyads within and among communities did not yield conclusive results. HVRI diversity within communities was high and did not differ between the sexes, also suggesting female gene flow. Our study is the first comprehensive analysis of the genetic population structure in Guinea baboons and provides evidence for female‐biased dispersal in this species. In conjunction with their multilevel social organization, this finding parallels the observations for human hunter‐gatherers and strengthens baboons as an intriguing model to elucidate the processes that shaped the highly cooperative societies of Homo. Am. J. Primatol. 77:878–889, 2015. © 2015 The Authors. American Journal of Primatology Published by Wiley Periodicals Inc.     

Preserving quantifiable ethnographic records of disappearing human lifeways

The human evolutionary sciences place high value on quantitative data from traditional small‐scale societies that are rapidly modernizing. These data often stem from the sustained ethnographic work of anthropologists who are today nearing the end of their careers. Yet many quantitative ethnographic data are preserved only in summary formats that do not reflect the rich and variable ethnographic reality often described in unpublished field notes, nor the deep knowledge of their collectors. In raw disaggregated formats, such data have tremendous scientific value when used in conjunction with modern statistical techniques and as part of comparative analyses. Through a personal example of longitudinal research with Batek hunter‐gatherers that involved collaboration across generations of researchers, we argue that quantifiable ethnographic records, just like material artifacts, deserve high‐priority preservation efforts. We discuss the benefits, challenges, and possible avenues forward for digitizing, preserving, and archiving ethnographic data before it is too late.     

Amazonian horticulturalists live in larger,more related groups than hunter–gatherers

The relatedness of human groups has important ramifications for kin (group) selection to favor more collective action and invites the potential for more exploitation by political leaders. Endogamous marriages among kin create intensive kinship systems with high group relatedness, while exogamous marriages among nonrelatives create extensive kinship with low group relatedness. Here, a sample of 58 societies (7,565 adults living in 353 residential groups) shows that average group relatedness is higher in lowland horticulturalists than in hunter–gatherers. Higher relatedness in horticulturalists is remarkable given that village sizes are larger, harboring over twice the average number of adults than in hunter–gatherer camps. The relatedness differential between subsistence regimes increases for larger group sizes. Large and dense networks of kin may have favored an increased propensity for some forms of in-group cooperation and political inequality that emerged relatively recently in human history, after the advent of farming.     

Ecological and evolutionary implications of food subsidies from humans

Human activities are the main current driver of global change. From hunter‐gatherers through to Neolithic societies–and particularly in contemporary industrialised countries–humans have (voluntarily or involuntarily) provided other animals with food, often with a high spatio‐temporal predictability. Nowadays, as much as 30–40% of all food produced in Earth is wasted. We argue here that predictable anthropogenic food subsidies (PAFS) provided historically by humans to animals has shaped many communities and ecosystems as we see them nowadays. PAFS improve individual fitness triggering population increases of opportunistic species, which may affect communities, food webs and ecosystems by altering processes such as competition, predator–prey interactions and nutrient transfer between biotopes and ecosystems. We also show that PAFS decrease temporal population variability, increase resilience of opportunistic species and reduce community diversity. Recent environmental policies, such as the regulation of dumps or the ban of fishing discards, constitute natural experiments that should improve our understanding of the role of food supply in a range of ecological and evolutionary processes at the ecosystem level. Comparison of subsidised and non‐subsidised ecosystems can help predict changes in diversity and the related ecosystem services that have suffered the impact of other global change agents.