Evidence that cultural groups differ in their abilities to detect fake accents.

Previous research in the evolutionary and psychological sciences has suggested that markers or tags of ethnic or group membership may help to solve cooperation and coordination problems. Cheating remains, however, a problem for these views, insofar as it is possible to fake the tag. While evolutionary psychologists have suggested that humans evolved the propensity to overcome this free rider problem, it is unclear how this module might manifest at the group level.

Diversity-dependent speciation and extinction in hominins.

The search for drivers of hominin speciation and extinction has tended to focus on the impact of climate change. Far less attention has been paid to the role of interspecific competition. However, research across vertebrates more broadly has shown that both processes are often correlated with species diversity, suggesting an important role for interspecific competition.

Hunter-Gatherer children's close-proximity networks: Similarities and differences with cooperative and communal breeding systems.

Among vertebrates, allomothering (non-maternal care) is classified as cooperative breeding (help from sexually mature non-breeders, usually close relatives) or communal breeding (shared care between multiple breeders who are not necessarily related). Humans have been described with both labels, most frequently as cooperative breeders. However, few studies have quantified the relative contributions of allomothers according to whether they are (a) sexually mature and reproductively active and (b) related or unrelated.

Ghosts of extinct apes: genomic insights into African hominid evolution.

We are accustomed to regular announcements of new hominin fossils. There are now some 6000 hominin fossils, and up to 31 species. However, where are the announcements of African ape fossils? The answer is that there are almost none.

The Distribution and Biogenic Origins of Zinc in the Mineralised Tooth Tissues of Modern and Fossil Hominoids: Implications for Life History, Diet and Taphonomy.

Zinc is incorporated into enamel, dentine and cementum during tooth growth. This work aimed to distinguish between the processes underlying Zn incorporation and Zn distribution. These include different mineralisation processes, the physiological events around birth, Zn ingestion with diet, exposure to the oral environment during life and diagenetic changes to fossil teeth .

Sensitive responsiveness and multiple caregiving networks among Mbendjele BaYaka hunter-gatherers: Potential implications for psychological development and well-being.

Attachment theory postulates that there is a particular style of caregiving that, because of its interaction with our evolved psychology, is most likely to result in healthy psychological development. Attachment research has been criticized because most studies have been conducted with Western populations. Critics argue this has (a) overemphasized the importance of sensitive responsive caregiving and (b) limited our understanding of multiple nonmaternal caregiving (allomothering).

Cooperation and partner choice among Agta hunter-gatherer children: An evolutionary developmental perspective.

Examining development is essential for a full understanding of behaviour, including how individuals acquire traits and how adaptive evolutionary forces shape these processes. The present study explores the development of cooperative behaviour among the Agta, a Filipino hunter-gatherer population. A simple resource allocation game assessing both levels of cooperation (how much children shared) and patterns of partner choice (who they shared with) was played with 179 children between the ages of 3 and 18.

Editorial Perspective: What can we learn from hunter-gatherers about children's mental health? An evolutionary perspective.

Humans lived as hunter-gatherers for more than 95% of our evolutionary history, thus studying contemporary hunter-gatherer populations offers insight into the conditions children may be psychologically adapted to. Here, we contrast hunter-gatherer childhoods with those of WEIRD (Western Educated Industrialised Rich Democratic) societies and consider the implications for children's mental health. Hunter-gatherer infants receive continuous physical contact and more sensitive and responsive caregiving than is typical of WEIRD societies, due to the extensive involvement of alloparents (non-parental caregivers) who generally provide 40-50% of their care.

Seasonal resource categorisation and behavioral adaptation among chimpanzees: Implications for early hominin carnivory.

Seasonality plays a critical role in determining the yearly dietary variability of many nonhuman primates living in tropical and subtropical environments. Much previous research has emphasised the seasonal importance of both preferred resources-eaten whenever available-and fallback foods-eaten during periods of scarcity to compensate for an insufficient availability of preferred resources. However, previous discussions of this dichotomy have often overlooked why different populations of the same taxon may exhibit a different level of engagement with identical resources, especially those that require additional technological investment by virtue of being embedded.

Patterns of variation in canal and root number in human post-canine teeth.

Descriptive morphology of tooth roots traditionally focuses on number of canals and roots. However, how or if canal and root number are related is poorly understood. While it is often assumed that canal number is concomitant with root number and morphology, in practice canal number and morphology do not always covary with external root features.

A process-based approach to hominin taxonomy provides new perspectives on hominin speciation.

A longstanding debate in hominin taxonomy is that between "lumpers" and "splitters." We argue that both approaches assume an unrealistically static model of speciation. Speciation is an extended process, of which fossils provide a record.

Age of the oldest known Homo sapiens from eastern Africa.

Efforts to date the oldest modern human fossils in eastern Africa, from Omo-Kibish and Herto in Ethiopia, have drawn on a variety of chronometric evidence, including Ar/Ar ages of stratigraphically associated tuffs. The ages that are generally reported for these fossils are around 197 thousand years (kyr) for the Kibish Omo I, and around 160-155 kyr for the Herto hominins. However, the stratigraphic relationships and tephra correlations that underpin these estimates have been challenged.

The Role of Language in Structuring Social Networks Following Market Integration in a Yucatec Maya Population.

Language is the human universal mode of communication, and is dynamic and constantly in flux accommodating user needs as individuals interface with a changing world. However, we know surprisingly little about how language responds to market integration, a pressing force affecting indigenous communities worldwide today. While models of culture change often emphasize the replacement of one language, trait, or phenomenon with another following socioeconomic transitions, we present a more nuanced framework.

Genetic architecture of gene regulation in Indonesian populations identifies QTLs associated with global and local ancestries.

Lack of diversity in human genomics limits our understanding of the genetic underpinnings of complex traits, hinders precision medicine, and contributes to health disparities. To map genetic effects on gene regulation in the underrepresented Indonesian population, we have integrated genotype, gene expression, and CpG methylation data from 115 participants across three island populations that capture the major sources of genomic diversity in the region. In a comparison with European datasets, we identify eQTLs shared between Indonesia and Europe as well as population-specific eQTLs that exhibit differences in allele frequencies and/or overall expression levels between populations.

A novel system for classifying tooth root phenotypes.

Human root and canal number and morphology are highly variable, and internal root canal form and count does not necessarily co-vary directly with external morphology. While several typologies and classifications have been developed to address individual components of teeth, there is a need for a comprehensive system, that captures internal and external root features across all teeth. Using CT scans, the external and internal root morphologies of a global sample of humans are analysed (n = 945).

Quantifying patterns of alcohol consumption and its effects on health and wellbeing among BaYaka hunter-gatherers: A mixed-methods cross-sectional study.

Ethnographers frequently allude to alcoholism and related harms in Indigenous hunter-gatherer communities, but very few studies have quantified patterns of alcohol consumption or its health and social impacts. We present a case study of the Mbendjele BaYaka, a Congolese population undergoing socioeconomic transition. 83 adults answered questions about their frequency and quantity of alcohol consumption, underwent biometric measurements and reported whether they were currently experiencing a cough or diarrhoea; 56 participated in structured interviews about their experiences with alcohol.

The evolution of barriers to exploitation: Sometimes the Red Queen can take a break.

We propose a general barrier theory as an evolutionary framework for understanding coevolutionary effects of conflicts of interest in natural and human systems. It is generalized from the barrier theory of cancer, which describes how cancer develops through the evasion of mechanisms, that block unregulated cellular reproduction and survival. Barriers are naturally evolved or artificially implemented mechanisms for blocking exploitation; restraints are mechanisms that impede but do not block exploitation.

Contagion culture.

The new social norm of isolating when ill with covid-19 should apply to other infectious diseases such as flu, says .

Seasonality and Oldowan behavioral variability in East Africa.

The extent, nature, and temporality of early hominin food procurement strategies have been subject to extensive debate. In this article, we examine evidence for the seasonal scheduling of resource procurement and technological investment in the Oldowan, starting with an evaluation of the seasonal signature of underground storage organs, freshwater resources, and terrestrial animal resources in extant primates and modern human hunter-gatherer populations. Subsequently, we use the mortality profiles, taxonomic composition, and taphonomy of the bovid assemblages at Kanjera South (Homa Peninsula, Kenya) and FLK-Zinj (Olduvai Gorge, Tanzania) to illustrate the behavioral flexibility of Oldowan hominins, who were targeting different seasonally vulnerable demographics.

The discovery of an in situ Neanderthal remain in the Bawa Yawan Rockshelter, West-Central Zagros Mountains, Kermanshah.

Neanderthal extinction has been a matter of debate for many years. New discoveries, better chronologies and genomic evidence have done much to clarify some of the issues. This evidence suggests that Neanderthals became extinct around 40,000-37,000 years before present (BP), after a period of coexistence with Homo sapiens of several millennia, involving biological and cultural interactions between the two groups.