Oxytocin promotes convergence in personality between members of a monogamous pair

Social context is critical in shaping behavioral responses to stimuli and can alter an individual’s behavioral type, which would otherwise be fixed in social isolation. For monogamous biparental vertebrates, social context is critical as interactions are frequent and consistent, involving high interindividual dependence and cooperation that can lead to large fitness impacts. We demonstrate that in the strictly monogamous and highly territorial California mouse, individuals alter approach response to an aggressive conspecific playback stimulus, barks, to become more similar to their partner during early bonding prior to pup birth; an effect distinct from assortative mating. Additionally, sustained vocalizations, an affiliative ultrasonic vocalization when used between pair members, correlate with increased behavioral convergence following pair formation suggesting a role for vocal communication in emergent pair behavior. We identified the neuropeptide oxytocin as sufficient to promote behavioral convergence in approach behavior of paired individuals who differed in their initial behavioral type. Social context, specifically pair-bonding, appears vital for behavioral responses to aggressive signals. While non-bonded animals maintained stable responses, pair-bonding led to an emergent property: convergence in behavioral responses. This convergence can be driven by oxytocin revealing a significant expansion in oxytocin’s effects on behavioral coordination.

An ancient push-pull pollination mechanism in cycads

Most cycads engage in brood-site pollination mutualisms, yet the mechanism by which the Cycadales entice pollination services from diverse insect mutualists remains unknown. Here, we characterize a push-pull pollination mechanism between a New World cycad and its weevil pollinators that mirrors the mechanism between a distantly related Old World cycad and its thrips pollinators. The behavioral convergence between weevils and thrips, combined with molecular phylogenetic dating and a meta-analysis of thermogenesis and coordinated patterns of volatile attraction and repulsion suggest that a push-pull pollination mutualism strategy is ancestral in this ancient, dioecious plant group. Hence, it may represent one of the earliest insect/plant pollination mechanisms, arising long before the evolution of visual floral signaling commonly used by flowering plants.

Familiar faces, familiar spaces: Social similarity and co-presence in non-relational behavioral convergence

Social influence is frequently measured through an ego's direct ties. Although influence may also stem from an ego's indirect ties, reference group, and casual contacts, it is difficult to capture their impact using existing network methods. We identify and trace the influence stemming from an ego's “familiar others,” consisting of those socially similar individuals with whom the ego comes in contact at school, but does not necessarily share a relationship. To evaluate the role of familiar others, we investigate unhealthy weight behaviors in adolescence using data from the National Longitudinal Study of Adolescent to Adult Health. Our results demonstrate that familiar others' unhealthy weight-related behaviors are strong predictors of the ego's own weight behaviors, net of immediate alters' behaviors, and individual-level characteristics. Further, we find that this relationship is stronger and more robust than that between egos and their direct ties. These results suggest that familiar others constitute a key source of social influence that is distinct from the influence of network alters.

Role-Related Participation in Product Design Teams

Organizations often delegate decision-making tasks to groups and teams. At issue is the extent to which participation during discussion reflects both individual-level characteristics and emergent (i.e., group-level) processes. Drawing upon Hewes’s socio-egocentric model and team meeting literature, we used a multilevel approach to examine participation in product-design teams across a series of tasks. Findings indicate that participation consists of both intra- and group-level processes. Team members who were talkative initially continued to participate frequently during the later tasks, and, as predicted, project managers also spoke more often than team members in any other role. In addition, group-level trends became stronger over time, as evidenced by behavioral convergence. Discussion addresses implications for a “middle ground” approach to modeling communicative behavior in groups.

Socio-behavioral convergence in female affiliative behaviors in Pan and Ateles

Pan and Ateles converge in many aspects of their social organization. Both are characterized by a high degree of fission-fusion dynamics, in which species exhibit high variation in party size, composition, and spatial cohesion. Within this framework, chimpanzees (Pan troglodytes) and spider monkeys (Ateles sp.) exhibit the most similarity in subgrouping patterns and social relationships. Specifically, significant overlap is found in the context of female social relationships and patterns of male-female aggression. Here, we examine how affiliative behaviors mediate female social relationships in captive spider monkeys, chimpanzees, and bonobos. Focal data were collected from five female Ateles geoffroyi at Brookfield Zoo (mean age=13.2, range: 7-21), five female bonobos at Columbus Zoo (mean age=22.0, range: 7-31), and five chimpanzees at North Carolina Zoo (mean age=20.4, range: 15-43). Female dyads did not differ in their rates of total or directional grooming, but spider monkeys engaged in significantly less mutual grooming (Kruskal-Wallis H= 8.917, N=30, p=0.012). All three species exhibited grooming reciprocity. There were no significant differences in the overall use of tension-reduction behaviors. However, there were significant differences in the types of tension-reduction behaviors, with spider monkeys using embraces (H=14.306, p=0.001), bonobos using socio-sexual behaviors (H=14.269, p=0.001), and chimpanzees using kisses (H=11.50, p=0.003). Furthermore, bonobos used tension-reduction behaviors significantly more often in feeding contexts (ANOVA F=14.357, N=15, p=0.001). We suggest that each species use tension-reduction behaviors that are species-typical, but serve as functional equivalents. However, bonobos may experience increased tension in feeding contexts, which suggests differing social and ecological pressures may necessitate an increase in tension-reduction behaviors.

Socio-behavioral convergence in female affiliative behaviors in Pan and Ateles

Pan and Ateles converge in many aspects of their social organization. Both are characterized by a high degree of fission-fusion dynamics, in which species exhibit high variation in party size, composition, and spatial cohesion. Within this framework, chimpanzees (Pan troglodytes) and spider monkeys (Ateles sp.) exhibit the most similarity in subgrouping patterns and social relationships. Specifically, significant overlap is found in the context of female social relationships and patterns of male-female aggression. Here, we examine how affiliative behaviors mediate female social relationships in captive spider monkeys, chimpanzees, and bonobos. Focal data were collected from five female Ateles geoffroyi at Brookfield Zoo (mean age=13.2, range: 7-21), five female bonobos at Columbus Zoo (mean age=22.0, range: 7-31), and five chimpanzees at North Carolina Zoo (mean age=20.4, range: 15-43). Female dyads did not differ in their rates of total or directional grooming, but spider monkeys engaged in significantly less mutual grooming (Kruskal-Wallis H= 8.917, N=30, p=0.012). All three species exhibited grooming reciprocity. There were no significant differences in the overall use of tension-reduction behaviors. However, there were significant differences in the types of tension-reduction behaviors, with spider monkeys using embraces (H=14.306, p=0.001), bonobos using socio-sexual behaviors (H=14.269, p=0.001), and chimpanzees using kisses (H=11.50, p=0.003). Furthermore, bonobos used tension-reduction behaviors significantly more often in feeding contexts (ANOVA F=14.357, N=15, p=0.001). We suggest that each species use tension-reduction behaviors that are species-typical, but serve as functional equivalents. However, bonobos may experience increased tension in feeding contexts, which suggests differing social and ecological pressures may necessitate an increase in tension-reduction behaviors.