Effective incentives for increasing COVID-19 vaccine uptake

In this study, we examined the relative effectiveness of prestige-based incentives (vaccination of an expert scientist/president/politician/celebrity/religious leader), conformist incentives (vaccination of friends and family) and risk-based incentives (witnessing death or illness of a person from the disease) for increasing participants' chances of getting vaccinated with respect to their coronavirus disease 2019 (COVID-19) vaccine intention. We conducted a cross-cultural survey using demographically representative samples from the UK (n = 1533), USA (n = 1550) and Turkey (n = 1567). The most effective incentives in all three countries were vaccination of an expert scientist, followed by vaccination of friends and family members and knowing someone dying from the disease. Vaccination of an expert scientist was significantly more effective at increasing vaccine intention than any other incentive. Vaccine incentives, regardless of the incentive type, were much less effective for those who originally refused the COVID-19 vaccine than for those who were hesitant to receive the vaccine. Although the percentage of vaccine-hesitant participants was highest in Turkey, the mean effectiveness scores of incentives were also the highest in Turkey, suggesting that an informed vaccine promotion strategy can be successful in this country. Our findings have policy applicability and suggest that positive vaccination messages delivered by expert scientists, vaccination of friends and family and risk-based incentives can be effective at increasing vaccine uptake

Social structure and knowledge sharing networks in hunter-gatherers: A case study on the plant knowledge of the Mbendjele BaYaka Pygmies

Hunters and gatherers occupied 95% of the human history. Despite the forces of globalization, current-day hunter-gatherers can shed light on how we adapted to different environments and generated complex cultural traits. Their changing ways of life, on the other hand, may let us understand cultural change. In this thesis, I explore the cultural evolution of plant knowledge in an extant hunter-gatherer population, the Mbendjele BaYaka Pygmies from the Northern Republic of Congo. In Chapter 4, I show that the Mbendjele use wild plants for various reasons from treating digestive system disorders to punishing norm violators. In Chapter 5, I investigate whether there are adaptive benefits to the use of certain medicinal plants and explore the common uses of medicinal plants across different Pygmy populations and great apes. I also explore the known bioactive compounds, and test the effects of mothers’ use of certain medicinal plants on their children’s body- mass-index. In Chapter 6, I investigate how the Mbendjele have evolved such a rich plant use repertoire by exploring sharing of medicinal and non-medicinal plant knowledge with respect to features of social structure. I argue that the long-term pair bonds, marital ties and cooperative breeding have allowed the Mbendjele to combine and accumulate rich medicinal plant uses. Additionally, co-residence of multiple families provides a context for the sharing and accumulation of plant uses that concern cooperative foraging and social norms. In Chapter 7, I explore the socioeconomic transitions in the Mbendjele that live in a logging town and examine how plant knowledge declines with their changing life-style. I argue that change in subsistence activities, emerging inequalities and decreased mobility hinder the transmission of traditional knowledge. Nevertheless, I argue that adoption of new cultural traits may be inevitable and beneficial for the resilience of modern day hunter-gatherers

Adaptive function and correlates of anxiety during a pandemic

Background and objectives: Most studies to date have focused on the negative aspects of anxiety. Anxiety, however, is an evolved emotional response that can provide protection in the face of risk. Pandemics are characterized by increased mortality risk coupled with future uncertainties, which both cause heightened anxiety. Here, we examine the factors associated with anxiety levels and risk avoidance behaviours during the first wave of the COVID-19 pandemic. We asked how individual time perspectives (future-oriented consideration and attention to present moment experience) affect anxiety in uncertain times, and whether anxiety reduces mortality risk by promoting risk avoidance behaviour. / Methodology: We conducted an online survey in the UK (N = 1088) and Turkey (N = 3935) and measured participants’ generalized and pandemic-related anxiety levels, future-oriented consideration, mindfulness, intolerance of uncertainty, risk perception and risk avoidance behaviours. / Results: We found that people less tolerant of uncertainties had higher levels of pandemic anxiety. Those with higher pandemic anxiety exhibited risk avoidance behaviours more frequently. Mindfulness and increased financial satisfaction reduced pandemic anxiety. People in Turkey reported higher levels of generalized and pandemic anxiety and greater engagement in risk avoidance behaviours than people in the UK. / Conclusions and implications: Our study shows an elevated anxiety response can help mitigate infection risk during pandemics and emphasizes the importance of the underlying situation in understanding whether an anxiety response is adaptive or pathological. Maintaining a healthy level of anxiety can promote engagement in protective behaviours. Therapies addressing anxiety can focus on increasing tolerance to future uncertainties

Development of social learning and play in BaYaka hunter-gatherers of Congo

High-fidelity transmission of information through imitation and teaching has been proposed as necessary for cumulative cultural evolution. Yet, it is unclear when and for which knowledge domains children employ different social learning processes. This paper explores the development of social learning processes and play in BaYaka hunter-gatherer children by analysing video recordings and time budgets of children from early infancy to adolescence. From infancy to early childhood, hunter-gatherer children learn mainly by imitating and observing others' activities. From early childhood, learning occurs mainly in playgroups and through practice. Throughout childhood boys engage in play more often than girls whereas girls start foraging wild plants from early childhood and spend more time in domestic activities and childcare. Sex differences in play reflect the emergence of sexual division of labour and the play-work transition occurring earlier for girls. Consistent with theoretical models, teaching occurs for skills/knowledge that cannot be transmitted with high fidelity through other social learning processes such as the acquisition of abstract information e.g. social norms. Whereas, observational and imitative learning occur for the transmission of visually transparent skills such as tool use, foraging, and cooking. These results suggest that coevolutionary relationships between human sociality, language and teaching have likely been fundamental in the emergence of human cumulative culture

Global WEIRDing: Transitions in Wild Plant Knowledge and Treatment Preferences in Congo Hunter-Gatherers

Cultures around the world are converging as populations become more connected. On the one hand this increased connectedness can promote the recombination of existing cultural practices to generate new ones, but on the other it may lead to the replacement of traditional practices and global WEIRDing. Here we examine the process and causes of changes in cultural traits concerning wild plant knowledge in Mbendjele BaYaka hunter–gatherers from Congo. Our results show that the BaYaka who were born in town reported knowing and using fewer plants than the BaYaka who were born in forest camps. Plant uses lost in the town-born BaYaka related to medicine. Unlike the forest-born participants, the town-born BaYaka preferred Western medicine over traditional practices, suggesting that the observed decline of plant knowledge and use is the result of replacement of cultural practices with the new products of cumulative culture

Characterization of hunter-gatherer networks and implications for cumulative culture

Social networks in modern societies are highly structured, usually involving frequent contact with a small number of unrelated friends' 1. However, contact network structures in traditional small-scale societies, especially hunter-gatherers, are poorly characterized. We developed a portable wireless sensing technology (motes) to study within-camp proximity networks among Agta and BaYaka hunter-gatherers in fine detail. We show that hunter-gatherer social networks exhibit signs of increased efficiency 2 for potential information exchange. Increased network efficiency is achieved through investment in a few strong links among non-kin friends' connecting unrelated families. We show that interactions with non-kin appear in childhood, creating opportunities for collaboration and cultural exchange beyond family at early ages. We also show that strong friendships are more important than family ties in predicting levels of shared knowledge among individuals. We hypothesize that efficient transmission of cumulative culture 3-6 may have shaped human social networks and contributed to our tendency to extend networks beyond kin and form strong non-kin ties

Hunter-Gatherer Children’s Close-Proximity Networks: Similarities and differences with cooperative and communal breeding systems.

Research transparency and reproducibility: Processed data that support the findings of this study are available here: https://osf.io/n4b9e/Supplementary material: The supplementary material for this article can be found at https://doi.org/10.1017/ehs.2024.1 .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. We constructed close-proximity networks of Agta and BaYaka hunter–gatherers. We used portable remote-sensing devices to quantify the proportion of time children under the age of 4 spent in close proximity to different categories of potential allomother. Both related and unrelated, and reproductively active and inactive, campmates had substantial involvement in children's close-proximity networks. Unrelated campmates, siblings and subadults were the most involved in both populations, whereas the involvement of fathers and grandmothers was the most variable between the two populations. Finally, the involvement of sexually mature, reproductively inactive adults was low. Where possible, we compared our findings with studies of other hunter–gatherer societies, and observed numerous consistent trends. Based on our results we discuss why hunter–gatherer allomothering cannot be fully characterised as cooperative or communal breeding.Leverhulme Trust (ABM, grant number RP2011-R-045). DM-S was also supported by the John Templeton Foundation (grant ID: 61917)

Women's subsistence strategies predict fertility across cultures, but context matters

Data, Materials, and Software Availability. Anonymized CSV file data have been deposited in OSF (https://osf.io/8d9n2/?view_only=9e07c25 e06414f7a8d041e80e8539e5c) (49).Supporting Information is available online at: https://www.pnas.org/doi/suppl/10.1073/pnas.2318181121/suppl_file/pnas.2318181121.sapp.pdf .While it is commonly assumed that farmers have higher, and foragers lower, fertility compared to populations practicing other forms of subsistence, robust supportive evidence is lacking. We tested whether subsistence activities—incorporating market integration—are associated with fertility in 10,250 women from 27 small-scale societies and found considerable variation in fertility. This variation did not align with group-level subsistence typologies. Societies labeled as “farmers” did not have higher fertility than others, while “foragers” did not have lower fertility. However, at the individual level, we found strong evidence that fertility was positively associated with farming and moderate evidence of a negative relationship between foraging and fertility. Markers of market integration were strongly negatively correlated with fertility. Despite strong cross-cultural evidence, these relationships were not consistent in all populations, highlighting the importance of the socioecological context, which likely influences the diverse mechanisms driving the relationship between fertility and subsistence.A.E.P. received funding from the Medical Research Council MRC (grant no. MR/P014216/1). J.S. acknowledges Institute for Advanced Study in Toulouse funding from the French National Research Agency (ANR) under the Investments for the Future (Investissements d’Avenir) program, grant ANR-17-EURE-0010. This material is based upon work supported while S.M. served at the National Science Foundation (NSF)

Human behavior. Sex equality can explain the unique social structure of hunter-gatherer bands.

The social organization of mobile hunter-gatherers has several derived features, including low within-camp relatedness and fluid meta-groups. Although these features have been proposed to have provided the selective context for the evolution of human hypercooperation and cumulative culture, how such a distinctive social system may have emerged remains unclear. We present an agent-based model suggesting that, even if all individuals in a community seek to live with as many kin as possible, within-camp relatedness is reduced if men and women have equal influence in selecting camp members. Our model closely approximates observed patterns of co-residence among Agta and Mbendjele BaYaka hunter-gatherers. Our results suggest that pair-bonding and increased sex egalitarianism in human evolutionary history may have had a transformative effect on human social organization