The dynamics of sociality and glucocorticoids in wild male Assamese macaques.

For males of gregarious species, dominance status and the strength of affiliative relationships can have major fitness consequences. Social dynamics also impose costs by affecting glucocorticoids, mediators of homeostasis and indicators of the physiological response to challenges and within-group competition. We investigated the relationships between dominance, social bonds, seasonal challenges, and faecal glucocorticoid metabolite (fGC) measures in wild Assamese macaques (Macaca assamensis) at Phu Khieo Wildlife Sanctuary, Thailand, combining behavioural data with 4129 samples from 62 adult males over 15 years. Our previous work on this population suggested that increased competition during the mating season was associated with elevated fGC levels and that, unusually for male primates, lower rank position correlated with higher fGC levels. With a much larger dataset and dynamic measures of sociality, we re-examined these relationships and additionally tested the potentially fGC-attenuating effect of social support. Contrary to our previous study, yet consistent with the majority of work on male primates, dominance rank had a positive relationship with fGC levels, as high status correlated with elevated glucocorticoid measures. fGC levels were increased at the onset of the mating season. We demonstrated an fGC-reducing effect of supportive relationships in males and showed that dynamics in affiliation can correlate with dynamics in physiological responses. Our results suggest that in a system with intermediate contest potential, high dominance status can impose physiological costs on males that may potentially be moderated by social relationships. We highlight the need to consider the dynamics of sociality and competition that influence hormonal processes.

Female social dynamics as viewed from grooming networks in the Central Himalayan Langur (Semnopithecus schistaceus).

Enhanced survival and reproduction are associated with an individual's direct and indirect social connections with members of a group. Yet, the role of these connections is little known in a vast range of primate species. We studied female Central Himalayan Langur (CHL) to investigate the link between four specific attributes (dominance rank, age, genetic relatedness, and the presence of females carrying infants) and a female's direct and indirect social relationships. By analyzing grooming networks, we revealed different behavioral strategies: high-ranking females form relationships with many females (high degree), whereas females with dependent infants have strong relationships (high strength and eigenvector). Subadult females are important individuals that hold the social network together (high betweenness), while an immigrant female strategy is to integrate herself into the group by forming strong bonds with females who themselves have strong bonds (high eigenvector). Our study sheds light on how behavioral strategies shape female CHL grooming networks, which may help them to secure fitness and survival advantages.

The incurable self: Negotiating social bonds and dis/connection with metastatic breast cancer.

As the culture of silence that once surrounded cancer has gradually given way to greater public awareness, normative visions of what cancer survivorship should entail have proliferated. These visions emphasise positivity and perseverance in pursuit of cure. While these visions provide comfort to many, for people with metastatic cancer, the emphasis on cure can undermine their sense of belonging to the broader collective of people living with cancer. Drawing on semi-structured interviews with 38 Australian women living with metastatic breast cancer, we explore how incurable cancer inflects understandings of self and transforms interpersonal relationships. Extending ideas around biosociality and belonging, we explore the tenuousness of social bonds, revealing how (in)visibility, (in)authenticity and (in)validation circulate within the daily lives of women with metastatic breast cancer. We conceptualise accounts according to four social bonds: (1) threatened bonds where a relationship is strained by misunderstanding, (2) severed bonds where a relationship is ruptured due to misunderstanding, (3) attuned bonds whereby a relationship is based on shared identification and (4) flexible social bonds when a relationship is based on mutual understanding. More broadly, we illustrate the persistence of normative visions of cancer survivorship and their enduring effects on those whom such visions exclude.

Shared stressful experiences affect social proximity in Merino sheep.

While it is well established that humans develop stronger relationship bonds when they share stressful experiences, there is little known on how shared stressful experiences may influence relationship bonding in animals. Here, we present a study looking at social proximity between individuals in small groups of Merino ewes following a shared stressful experience compared with control sheep that were not exposed to stress. Some sheep were familiar to each other. Analyses of social proximity using real-time-kinematic Global Navigation Satellite System (GNSS) on-animal devices showed sheep preferred to be closest to familiar individuals, but across the study duration they also developed a preference for the individuals they shared the stressful experience with, relative to their proximity to control individuals. These results contribute to limited research on what factors may instigate the development of bonds between unfamiliar sheep. Between-individual bonds may develop as a means of socially mediated stress buffering. Social bonding following a shared stressful experience aligns with human social relationships and increases our understanding of how animals perceive their conspecifics in relation to stressful environmental change.

Male-male relationships in chimpanzees and the evolution of human pair bonds.

The evolution of monogamy has been a central question in biological anthropology. An important avenue of research has been comparisons across "socially monogamous" mammals, but such comparisons are inappropriate for understanding human behavior because humans are not "pair living" and are only sometimes "monogamous." It is the "pair bond" between reproductive partners that is characteristic of humans and has been considered unique to our lineage. I argue that pair bonds have been overlooked in one of our closest living relatives, chimpanzees. These pair bonds are not between mates but between male "friends" who exhibit enduring and emotional social bonds. The presence of such bonds in male-male chimpanzees raises the possibility that pair bonds emerged earlier in our evolutionary history. I suggest pair bonds first arose as "friendships" and only later, in the human lineage, were present between mates. The mechanisms for these bonds were co-opted for male-female bonds in humans.

School engagement, school climate and youth externalizing behaviors: direct and indirect effects of parenting practices.

This research aimed to explore the direct and indirect effects of students' school engagement, school climate and parenting practices on youth's externalizing behaviors. A quantitative methodology with a sample of 183 Portuguese students, aged between 11 and 16 years old, was used. The main results suggested negative associations between externalizing behaviors and higher levels of school engagement and positive school climate. Poor parental supervision, inconsistent discipline and corporal punishment were positively related with externalizing behaviors, contrary to parental involvement and positive parenting that were associated with lower levels of externalizing behaviors. However, negative parenting practices were associated with lower levels of school engagement. Additionally, the results indicated that parenting practices might influence youth's externalizing behaviors through school engagement.

Male-male social bonding, coalitionary support and reproductive success in wild Guinea baboons.

Male-male bonds may confer substantial fitness benefits. The adaptive value of these relationships is often attributed to coalitionary support, which aids in rank ascension and female defence, ultimately resulting in greater reproductive success. We investigated the link between male-male sociality and both coalitionary support and reproductive success in wild Guinea baboons. This species lives in a tolerant multi-level society with reproductive units comprising a male and 1-6 females at the core. Males are philopatric, form differentiated, stable and equitable affiliative relationships (strong bonds) with other males, and lack a clear rank hierarchy. Here, we analysed behavioural and paternity data for 30 males and 50 infants collected over 4 years in the Niokolo-Koba National Park, Senegal. Strongly bonded males supported each other more frequently during conflicts, but strong bonds did not promote reproductive success. Instead, males that spent less time socializing with other males were associated with a higher number of females and sired more offspring. Notably, reproductively active males still maintained bonds with other males, but adjusted their social investment in relation to life-history stage. Long-term data will be needed to test if the adaptive value of male bonding lies in longer male tenure and/or in promoting group cohesion.

Following Other People's Footsteps: A Contextual-Attraction Effect Induced by Biological Motion.

Our visual system is bombarded with numerous social interactions that form intangible social bonds among people, as exemplified by synchronized walking in crowds. Here, we investigated whether these perceived social bonds implicitly intrude on visual perception and induce a contextual effect. Using multiple point-light walkers and a classical contextual paradigm, we tested 72 college-age adults across six experiments and found that the perceived direction of the central walker was attracted toward the direction of the surrounding walkers. The observed contextual-attraction effect occurred even when the surrounding walkers differed from the central walker in gender and walking speed but disappeared when they were asynchronously presented or replaced by inanimate motion. Strikingly, this contextual-attraction effect partially persisted in the context of local motion rather than static figures. These findings, in contrast to the typical contextual-repulsion effect, lend support for the distinctiveness of perceived social bonds on contextual modulation and suggest a specialized contextual mechanism tuned to social factors.

Why wait to mark? Possible reasons behind latency from olfactory exploration to overmarking in four African equid species.

Whereas most studies on overmarking in mammals analysed the rate of overmarking, that those investigate time between exploration of an olfactory stimulus and the response to it remain less common, with inconsistent results. We examined the latency in time between elimination by the sender and sniffing by the receiver, and from sniffing and overmarking, in four captive African equid species to explore differences among species, and among age and sex classes. We investigated these latency time periods in light of three potential hypotheses explaining overmarking behaviour in equids: social bonds, group cohesion, and intrasexual competition. Analysing 1684 events of sniffing and 719 of overmarking among 130 individuals, we found that (i) the time from elimination to overmarking was shorter among female friends and in parent-offspring dyads, proving support to the social bond hypothesis; (ii) intraspecific differences in time periods do not reflect the social organisation of species, thus not supporting the group cohesion hypothesis; (iii) males were more attracted to elimination of conspecifics than females, and female's eliminations were inspected longer, in line with the sexual competition hypothesis and/or reproductive behaviour. In addition, we found that the younger foals came to sniff eliminations faster than older ones, and in larger groups foals devoted longer time to sniffing the elimination before overmarking. We concluded that examination of the elimination could be driven by motivations other than the decision to overmark. Whereas overmarking serves to express bonds to a familiar individual, the latency of overmarking reflects more reproductive interests.

Joint intergroup aggression in female colobus monkeys (Colobus vellerosus) is associated with grooming bonds, male participation, and group size.

Cooperative home range defense is common in primates, despite a collective action problem that arises when group members benefit from winning the intergroup encounter regardless of whether they participate. The costs associated with this collective action problem may be mitigated by residing in small groups, residing with kin, or by forming strong bonds with group members. The potential to decouple the effects of these variables provided an opportunity to investigate which of these three variables best explains coparticipation in intergroup encounters among adult and subadult female colobus at Boabeng-Fiema, Ghana. Because males are often the main participants, we also investigated the relationship between female-female coparticipation and adult and subadult male participation. We collected intergroup behaviors from 94 adult and subadult individuals in eight groups during 1 year. We quantified female grooming bond strength and approach rates using focal samples. We classified female dyads as close kin (i.e., halfsiblings or more closely related) or nonkin based on partial pedigrees and genotypes generated from 17 STR loci. Female-female coparticipation was higher in dyads with stronger grooming bonds but was not associated with dyadic kinship, approach rate, or age class. Female coparticipation decreased with increasing female group size as expected if there is a collective action problem. Females coparticipated less in groups with more males and male intergroup aggression, possibly because there is less need for female-female cooperation if males are participating in the intergroup encounter. Females in smaller groups may not only benefit from increased female-female cooperation during intergroup encounters, they are also likely to reside with a higher-quality alpha male, both of which may increase the likelihood of winning intergroup encounters. There may be strong selection for facultative female dispersal in populations like the Boabeng-Fiema colobus in which small groups are associated with multiple benefits and cooperation is not affected by kinship.

Better baboon break-ups: collective decision theory of complex social network fissions.

Many social groups are made up of complex social networks in which each individual associates with a distinct subset of its groupmates. If social groups become larger over time, competition often leads to a permanent group fission. During such fissions, complex social networks present a collective decision problem and a multidimensional optimization problem: it is advantageous for each individual to remain with their closest allies after a fission, but impossible for every individual to do so. Here, we develop computational algorithms designed to simulate group fissions in a network-theoretic framework. We focus on three fission algorithms (democracy, community and despotism) that fall on a spectrum from a democratic to a dictatorial collective decision. We parameterize our social networks with data from wild baboons (Papio cynocephalus) and compare our simulated fissions with actual baboon fission events. We find that the democracy and community algorithms (egalitarian decisions where each individual influences the outcome) better maintain social networks during simulated fissions than despotic decisions (driven primarily by a single individual). We also find that egalitarian decisions are better at predicting the observed individual-level outcomes of observed fissions, although the observed fissions often disturbed their social networks more than the simulated egalitarian fissions.

Social Learning, Social Bonds, Self-Control and Adolescent Nicotine Vaping.

OBJECTIVES: The aim of this study was to examine whether three theories of adolescent substance use-social learning, social bonding, and self-control-were useful for predicting adolescent nicotine vaping. Methods: The analysis utilized data on U.S. 8th and 10th grade students from the 2017 and 2018 Monitoring the Future (MTF) studies, repeated cross-sectional surveys that included 11,624 youth who responded to questions about past 12-month nicotine vaping. Measures from each of the three theories were used to predict the outcome using a zero-inflated negative binomial model. Results: The results demonstrated that variables from social learning and self-control theories were key predictors of nicotine vaping. Friends' substance use appeared as the most consequential predictor, followed by low self-control or higher risk-taking propensities. An interaction effect also suggested that friends' substance use had a stronger association with nicotine vaping among youth who reported higher self-control. Conclusions/Importance: The findings suggested that adolescent nicotine vaping is a consequence of social learning influences and low self-control. Future research should explore these and similar factors in more detail.

Bonds of bros and brothers: Kinship and social bonding in postdispersal male macaques.

Group-living animals often maintain a few very close affiliative relationships-social bonds-that can buffer them against many of the inevitable costs of gregariousness. Kinship plays a central role in the development of such social bonds. The bulk of research on kin biases in sociality has focused on philopatric females, who typically live in deeply kin-structured systems, with matrilineal dominance rank inheritance and life-long familiarity between kin. Closely related males, in contrast, are usually not close in rank or familiar, which offers the opportunity to test the importance of kinship per se in the formation of social bonds. So far, however, kin biases in male social bonding have only been tested in philopatric males, where familiarity remains a confounding factor. Here, we studied bonds between male Assamese macaques, a species in which males disperse from their natal groups and in which male bonds are known to affect fitness. Combining extensive behavioural data on 43 adult males over a 10-year period with DNA microsatellite relatedness analyses, we find that postdispersal males form stronger relationships with the few close kin available in the group than with the average nonkin. However, males form the majority of their bonds with nonkin and may choose nonkin over available close kin to bond with. Our results show that kinship facilitates bond formation, but is not a prerequisite for it, which suggests that strong bonds are not restricted to kin in male mammals and that animals cooperate for both direct and indirect fitness benefits.

Oxytocin increases after affiliative interactions in male Barbary macaques.

Mammals living in stable social groups often mitigate the costs of group living through the formation of social bonds and cooperative relationships. The neuropeptide hormone oxytocin (OT) is proposed to promote both bonding and cooperation although only a limited number of studies have investigated this under natural conditions. Our aim was to assess the role of OT in bonding and cooperation in male Barbary macaques (Macaca sylvanus). First, we tested for an effect of affiliation - grooming and triadic male-infant-male interactions - with bond and non-bond partners on urinary OT levels. Second, we tested whether grooming interactions (and thus increased OT levels) increase a male's general propensity to cooperate in polyadic conflicts. We collected >4000 h of behavioral data on 14 adult males and measured OT levels from 139 urine samples collected after affiliation and non-social control periods. Urinary OT levels were higher after grooming with any partner. By contrast, OT levels after male-infant-male interactions with any partner or with bond partners were not different from controls but were higher after interactions with non-bond partners. Previous grooming did not increase the likelihood of males to support others in conflicts. Collectively, our results support research indicating that OT is involved in the regulation of adult affiliative relationships. However, our male-infant-male interaction results contradict previous studies suggesting that it is affiliation with bond rather than non-bond partners that trigger the release of OT. Alternatively, OT levels were elevated prior to male-infant-male interactions thus facilitating interaction between non-bond partners. The lack of an association of grooming and subsequent support speaks against an OT linked increase in the general propensity to cooperate.

Being liked or not being liked: A study on social-media exclusion in a preadolescent population.

INTRODUCTION: Social-media can contribute to building up adolescents' relationships, but they might also bring negative exclusionary experiences. Being excluded is a subtle yet hurtful form of relational aggression, which affects people's psychological wellbeing, especially during developmental stages. In this study, we (1) analyzed the effects of social-media exclusion adapting the Ostracism Online paradigm to a cohort of Italian preadolescents (Mage = 11.47, 53% girls) and (2) tested the efficacy of two potential recovery strategies (i.e., social bonds vs. social surrogate). METHOD: Inclusionary status was manipulated through the number of "likes" participants received on a fictitious online social network. In the exclusion condition, participants received fewer likes than everyone else. In the inclusion condition, participants received a similar number of likes of other users. Then, all participants were asked to think of a significant positive relationship with a family member (social bonds), a celebrity (social surrogate), their present moment thoughts (control). RESULTS: Preadolescents who received fewer likes than others reported higher levels of need threat (i.e., belong, self-esteem, meaningful existence, but not control) and negative emotions. Moreover, the social-bonds strategy generally brought a faster psychological recovery from social-media exclusion than the control condition. The efficacy of social-surrogates strategy was greater for boys than for girls, probably due to different choices in their favorite celebrities. CONCLUSION: These findings show how offline life offers compensatory opportunities for adolescents' online life. When the lack of "Likes" signal exclusion on social-media, thinking of an existing social relationship help adolescents to cope with this negative experience.

Examining the link between economic strain and adolescent social behavior: Roles of social bonds and empathy.

INTRODUCTION: The detrimental effect of economic strain on adolescent behavioral development is well established, but the mechanisms explaining this relationship are less known. This study aims to explore the psychosocial factors operating as pathways connecting economic strain to adolescent antisocial and prosocial behaviors, and examine whether these effects differ by gender. METHODS: The sample includes 1280 adolescents from middle and high schools in Hebei province, China (Mean age = 15.68 years; 52.6% girls), collected by a multi-stage cluster random sampling. Multi-group structural equation modeling is adopted for data analysis. RESULTS: Social bonds partially mediate the relationship between economic strain and adolescent antisocial behavior, and empathy fully mediates the relationship between economic strain and prosocial behavior after controlling for gender, age, household registration, and subjective socioeconomic status. In terms of gender differences, boys display more antisocial behaviors and less prosocial behaviors compared with girls. Significant gender differences are also found in the effect of economic strain on adolescent social behavior. CONCLUSIONS: This study contributes to current knowledge by revealing the psychosocial mechanisms between economic strain and adolescent antisocial/prosocial behaviors. Findings highlight the gender differences in behavioral development among Chinese adolescents.

Test of four hypotheses to explain the function of overmarking in foals of four equid species.

Overmarking occurs when one individual places its scent mark directly on top of the scent mark of another individual. Although it is almost ubiquitous among terrestrial mammals, we know little about the function of overmarking. In addition, almost all studies on mammalian overmarking behaviour dealt with adult individuals. Reports on this behaviour in juveniles are extremely rare, yet may elucidate the function of this behaviour. We tested four mutually non-exclusive hypotheses which might explain this behaviour in juveniles: (1) conceal the individual's scent identity, (2) announcement of association with other group members, especially the mother-i.e., sharing identity with the mother, (3) to prevent the next conception of the mother, i.e., parent-offspring conflict, and (4) an early expression of male sexual behaviour. We observed 43 foals (out of 108 individuals) from all African equid species (Equus africanus, E. grevyi, E. quagga, E. zebra) in five zoos. In total, we recorded 3340 eliminations; 260 of these events were overmarked by 38 individual foals representing all species. This represents one of the highest rates of overmarking ever recorded by mammalian juveniles. Foals of all species except African wild ass overmarked the mother more often than another herdmate: with male foals overmarked at a higher rate than female foals. Mothers preferred to overmark foals, but not exclusively their own foal. Our results provide support for the hypotheses that overmarking serves to share identity between foal and mother, and that it is an early expression of male sexual behaviour.

Persistence in gestural communication predicts sociality in wild chimpanzees.

A key challenge for primates is coordinating behaviour with conspecifics in large, complex social groups. Gestures play a key role in this process and chimpanzees show considerable flexibility communicating through single gestures, sequences of gestures interspersed with periods of response waiting (persistence), and rapid sequences where gestures are made in quick succession, too rapid for the response waiting to have occurred. The previous studies examined behavioural reactions to single gestures and sequences, but whether this complexity is associated with more complex sociality at the level of the dyad partner and the group as a whole is not well understood. We used social network analysis to examine how the production of single gestures and sequences of gestures was related to the duration of time spent in proximity and individual differences in proximity in wild East African chimpanzees (Pan troglodytes schweinfurthii). Pairs of chimpanzees that spent a longer duration of time in proximity had higher rates of persistence sequences, but not a higher rate of single gestures or rapid sequences. The duration of time spent in proximity was also related to the rate of responding to gestures, and response to gesture by activity change. These results suggest that communicative persistence and the type of response to gestures may play an important role in regulating social interactions in primate societies.

Wild birds respond to flockmate loss by increasing their social network associations to others.

Understanding the consequences of losing individuals from wild populations is a current and pressing issue, yet how such loss influences the social behaviour of the remaining animals is largely unexplored. Through combining the automated tracking of winter flocks of over 500 wild great tits (Parus major) with removal experiments, we assessed how individuals' social network positions responded to the loss of their social associates. We found that the extent of flockmate loss that individuals experienced correlated positively with subsequent increases in the number of their social associations, the average strength of their bonds and their overall connectedness within the social network (defined as summed edge weights). Increased social connectivity was not driven by general disturbance or changes in foraging behaviour, but by modifications to fine-scale social network connections in response to losing their associates. Therefore, the reduction in social connectedness expected by individual loss may be mitigated by increases in social associations between remaining individuals. Given that these findings demonstrate rapid adjustment of social network associations in response to the loss of previous social ties, future research should examine the generality of the compensatory adjustment of social relations in ways that maintain the structure of social organization.

Gossiping About Deviance: Evidence That Deviance Spurs the Gossip That Builds Bonds.

We propose that the gossip that is triggered when people witness behaviors that deviate from social norms builds social bonds. To test this possibility, we showed dyads of unacquainted students a short video of everyday campus life that either did or did not include an incident of negative or positive deviance (dropping or cleaning up litter). Study 1 showed that participants in the deviance conditions reported having a greater understanding of campus social norms than those in the control condition; they also expressed a greater desire to gossip about the video. Study 2 found that when given the opportunity, participants did gossip about the deviance, and this gossip was associated with increased norm clarification and (indirectly) social cohesion. These findings suggest that gossip may be a mechanism through which deviance can have positive downstream social consequences.