Variation In Social Organization Research Articles

Multi‐level framework to assess social variation in response to ecological and social factors: modeled with coral gobies

Understanding variation in social organization that lacks a strong phylogenetic signal represents a key focus of research in behavioural ecology. Accordingly, we established a framework that identifies whether a range of ecological and social factors are affecting the social maintenance of taxa across multiple categories of social variation (ranging from large to fine‐scale): 1) forms of sociality, 2) degree of sociality, 3) social plasticity and 4) hierarchy maintenance. Each category of variation can then be assessed in combination to provide an outlook for social maintenance in light of predictor factors. We modelled this framework by quantifying each category over time, space and disturbance regime using multiple species of coral‐dwelling gobies, genus Gobiodon. Gobies are an interesting model system as they vary in social structure, have within‐group cooperation, and form mutualisms with coral hosts, which are vulnerable to climatic disturbances. We found that gobies varied in forms of sociality – from being more solitary or pair‐forming in high disturbance regimes, versus group‐forming in moderate disturbance regimes at some locations. Only low or moderate degrees of sociality were observed in gobies, with location or disturbance regime affecting some species. The size of coral hosts influenced the social plasticity of gobies, which was affected by climatic disturbances. Gobies did not exhibit direct changes to hierarchy maintenance, as location and disturbance regime did not affect their size‐based hierarchies. Lastly, by combining the four categories of variation, we found a high loss of sociality in coral‐dwelling gobies due to environmental disturbances, which likely affects overall goby survival as group‐forming can improve survival and fitness. By using our structured framework, we identified which categories of social variation were influenced by ecological factors like location and disturbance. This framework therefore provides an excellent tool for predicting future responses of animal societies to environmental stressors.

Characterization of oxytocin and vasopressin receptors in the Southern giant pouched rat and comparison to other rodents.

Vasopressin and oxytocin are well known and evolutionarily ancient modulators of social behavior. The distribution and relative densities of vasopressin and oxytocin receptors are known to modulate the sensitivity to these signaling molecules. Comparative work is needed to determine which neural networks have been conserved and modified over evolutionary time, and which social behaviors are commonly modulated by nonapeptide signaling. To this end, we used receptor autoradiography to determine the distribution of vasopressin 1a and oxytocin receptors in the Southern giant pouched rat (Cricetomys ansorgei) brain, and to assess the relative densities of these receptors in specific brain regions. We then compared the relative receptor pattern to 23 other species of rodents using a multivariate ANOVA. Pouched rat receptor patterns were strikingly similar to hamsters and voles overall, despite the variation in social organization among species. Uniquely, the pouched rat had dense vasopressin 1a receptor binding in the caudate-putamen (i.e., striatum), an area that might impact affiliative behavior in this species. In contrast, the pouched rat had relatively little oxytocin receptor binding in much of the anterior forebrain. Notably, however, oxytocin receptor binding demonstrated extremely dense binding in the bed nucleus of the stria terminalis, which is associated with the modulation of several social behaviors and a central hub of the social decision-making network. Examination of the nonapeptide system has the potential to reveal insights into species-specific behaviors and general themes in the modulation of social behavior.

Primate social organization evolved from a flexible pair-living ancestor.

Explaining the evolution of primate social organization has been fundamental to understand human sociality and social evolution more broadly. It has often been suggested that the ancestor of all primates was solitary and that other forms of social organization evolved later, with transitions being driven by various life history traits and ecological factors. However, recent research showed that many understudied primate species previously assumed to be solitary actually live in pairs, and intraspecific variation in social organization is common. We built a detailed database from primary field studies quantifying the number of social units expressing different social organizations in each population. We used Bayesian phylogenetic models to infer the probability of each social organization, conditional on several socioecological and life history predictors. Here, we show that when intraspecific variation is accounted for, the ancestral social organization of primates was inferred to be variable, with the most common social organization being pair-living but with approximately 10 to 20% of social units of the ancestral population deviating from this pattern by being solitary living. Body size and activity patterns had large effects on transitions between types of social organizations. As in other mammalian clades, pair-living is closely linked to small body size and likely more common in ancestral species. Our results challenge the assumption that ancestral primates were solitary and that pair-living evolved afterward emphasizing the importance of focusing on field data and accounting for intraspecific variation, providing a flexible statistical framework for doing so.

Activity Budget and Sociality of the Northern Lesser Galago, Galago senegalensis

AbstractComplex sociality in primates often is argued to have evolved after the appearance of diurnal activity. Studying the behaviour of nocturnal primates is fundamental to understanding the evolutionary origins of primate behaviour and ecology, yet much less is known about the nature of sociality in nocturnal primate species than their diurnal counterparts. We investigated group size, communication, and social interactions in free-ranging, Northern lesser galagos (Galago senegalensis) and present an activity budget and assessment of temporal variation in their behaviour. We collected continuous behavioural data using focal follows at three different stages of the night from individuals at Kwakuchinja, Northern Tanzania. We also collected group size data from Northern lesser galagos at Fongoli, Southeastern Senegal, and Lolldaiga Hills Ranch, Central Kenya. We categorised behaviours and, where sample sizes permitted, used Kruskal–Wallis tests to compare the durations of observed behaviours between the morning (pre-dawn), evening (from dusk), and later in the night. We analysed 140 focal follows (31.4 h of continuous behavioural data) and found that the proportion of time spent foraging, inactive, in locomotion, in self-maintenance, and vigilant, varied across the three stages of the night; galagos spent a great deal of their time inactive in the morning and foraging was more prevalent in the evening. Group size at Kwakuchinja was significantly larger than at Fongoli or LHR. Galagos were in groups of two or more in the majority of encounters at Kwakuchinja (55%; N = 76), rather than alone, but spent most of their nighttime activity alone at Fongoli (79%; N = 185) and LHR (80%; N = 142). Overall vocalisation rates were higher in the morning than other times throughout the night, although contact calls were relatively more frequent in the evening than other times. We recorded both affiliative and agonistic social interactions, but these contributed almost nothing to the overall activity budget. Our preliminary investigation into the social structure of Northern lesser galagos suggests that there are population differences in sociality and that overall, they connect more through vocalisations than through direct social interactions, thereby avoiding some of the potential costs associated with group-living. This variation in social organization suggests that we have more to learn about the drivers of sociality in nocturnal primates and the nature of their social structure.

Beneath the surface: correlates of solitary, paired, and group living in a cryptic burrowing ghost shrimp Trypaea australiensis Dana, 1852 (Decapoda: Axiidea: Calianassidae)

Abstract Marine organisms, particularly invertebrates, are relatively understudied regarding social structure and behaviour, especially those that are cryptic. While empirically challenging to investigate, these species can provide novel insights into the evolution of sociality given their unique ecology. Our aim was to quantify in-situ the social structure and its underlying correlates in the Australian burrowing shrimp, Trypaea australiensis Dana, 1852 (Callianassidae). We show that T. australiensis exhibits intraspecific variation in social structure, being most often found in solitary arrangements, frequently in pairs (including homosexual and heterosexual arrangements), and sometimes in groups. The majority of shrimp in pairs and groups were found in heterosexual pairings or groups of one male and multiple females. Variation in social structure was correlated with variation in body size characteristics, seasonality, and site. These findings demonstrate that a wider array of social structures are exhibited by this species than previously expected, but the obvious limitations associated with sampling a cryptic burrowing species in situ mean that further investigations under controlled conditions, including laboratory behavioural manipulations, will be needed to confirm the current findings. The use of resin casts to understand burrow morphology would be important for understanding the causes of intraspecific variation in this and other cryptic species.

Photoperiod and rainfall are associated with seasonal shifts in social structure in a songbird

Abstract Seasonally breeding animals often exhibit different social structures during non-breeding and breeding periods that coincide with seasonal environmental variation and resource abundance. However, we know little about the environmental factors associated with when seasonal shifts in social structure occur. This lack of knowledge contrasts with our well-defined knowledge of the environmental cues that trigger a shift to breeding physiology in seasonally breeding species. Here, we identified some of the main environmental factors associated with seasonal shifts in social structure and initiation of breeding in the red-backed fairywren (Malurus melanocephalus), an Australian songbird. Social network analyses revealed that social groups, which are highly territorial during the breeding season, interact in social “communities” on larger home ranges during the non-breeding season. Encounter rates among non-breeding groups were related to photoperiod and rainfall, with shifting photoperiod and increased rainfall associated with a shift toward territorial breeding social structure characterized by reductions in home range size and fewer encounters among non-breeding social groups. Similarly, onset of breeding was highly seasonal and was also associated with non-breeding season rainfall, with greater rainfall leading to earlier breeding. These findings reveal that for some species, the environmental factors associated with the timing of shifts in social structure across seasonal boundaries can be similar to those that determine timing of breeding. This study increases our understanding of the environmental factors associated with seasonal variation in social structure and how the timing of these shifts may respond to changing climates.

The evolution of marsupial social organization.

It is generally believed that marsupials are more primitive than placentals mammals and mainly solitary living, representing the ancestral form of social organization of all mammals. However, field studies have observed pair and group-living in marsupial species, but no comparative study about their social evolution was ever done. Here, we describe the results of primary literature research on marsupial social organization which indicates that most species can live in pairs or groups and many show intra-specific variation in social organization. Using Bayesian phylogenetic mixed-effects models with a weak phylogenetic signal of 0.18, we found that solitary living was the most likely ancestral form (35% posterior probability), but had high uncertainty, and the combined probability of a partly sociable marsupial ancestor (65%) should not be overlooked. For Australian marsupials, group-living species were less likely to be found in tropical rainforest, and species with a variable social organization were associated with low and unpredictable precipitation representing deserts. Our results suggest that modern marsupials are more sociable than previously believed and that there is no strong support that their ancestral state was strictly solitary living, such that the assumption of a solitary ancestral state of all mammals may also need reconsideration.

A Comparative Study of Socio-Legal Scenarios in the COVID-19 Pandemic: Focusing on Asian Responses

AbstractThis article first distinguishes three governance scenarios that have been enacted in the COVID-19 pandemic, including identification and control; herd immunity without policy adjustments; and periodic lockdowns and hasty opening. In suggesting how different governments’ strategies were taxonomized into these categories, the paper examines major socio-legal challenges, including variations in social structures and government responsibilities; differences in public health cultures and legal policy options available to governments; unequal distribution of health and social welfare benefits; and public concerns of government overreach in relation to privacy of the infected and the preservation of individual liberty and freedom. Finally, the paper offers critical recommendations in the interest of ensuring a robust social-legal framework for providing adequate medical care to the infected; improving public health for vulnerable groups; ensuring that less privileged countries have access to vaccines; and designing post-disaster reconstruction by seeking global health objectives, rather than state-centric national justice.

Whistleblowing and Group Affiliation: The Role of Group Cohesion and the Locus of the Wrongdoer in Reporting Decisions

Conventional accounts describe whistleblowing as prosocial behavior, where whistleblowers are largely driven by a desire to help or improve their organization. Yet individuals are not only members of their organization; they also belong to internal social groups that affect behavior and influence decision making. In this paper, we focus on these intraorganizational dynamics and theorize two ways in which group affiliations are likely to affect whistleblowing. When an individual observes wrongdoing committed by a person affiliated with the same group, higher group cohesion decreases the likelihood of blowing the whistle because of potential whistleblowers’ greater loyalties toward group members and a desire to protect the reputation of the group. When an individual observes wrongdoing committed by a person not affiliated with the same group, higher group cohesion increases the likelihood of blowing the whistle, as potential whistleblowers feel they have the support of fellow group members, lessening fears of retaliation. Using unique data on actual and hypothetical whistleblowing among U.S. federal employees in 24 departments and agencies coupled with a vignette experiment, we find support for our arguments. By showing how group affiliations inform whistleblowing decisions, we reveal how variation in social structure leads to heterogeneity in responses to wrongdoing. Together, these results reveal tradeoffs in the detection of misconduct and help explain why wrongdoing in organizations may be so difficult to eradicate.

Evidence of male alliance formation in a small dolphin community

The photo-identification of uniquely marked individuals has revealed much about mammalian behaviour and social structure in recent decades. In bottlenose dolphins (Tursiops spp.), for example, the long-term tracking of individuals has unveiled considerable variation in social structure among populations and various spatio-temporal aspects of group formation. In this study, we investigated associations among individual males in a small community of Indo-Pacific bottlenose dolphins (T. aduncus) residing in an urbanized estuary in southwestern Australia. Given the relative proximity of our study area to other populations in which complex male alliances form for the purpose of mate acquisition, we used long-term photo-identification records and social analyses to assess whether such alliances also occur in smaller and more isolated settings. Our work revealed strong social bonds and long-term, non-random associations among individual males, suggesting the occurrence of male alliances. Behavioural observations of alliances interacting with potentially receptive adult females from the estuary community and from adjacent communities, and exhibiting sexual display behaviours near females, suggest that these alliances occur in a reproductive context. As the first formal analysis indicating the occurrence of male alliances outside Shark Bay along the vast western coastline of Australia, this study complements previous research and extends our understanding of the evolutionary and ecological processes that drive alliance formation.

A novel distribution of supergene genotypes is present in the socially polymorphic ant Formica neoclara

BackgroundSupergenes are chromosomal regions with tightly linked clusters of alleles that control compound phenotypic traits. Supergenes have been demonstrated to contribute to the maintenance of polymorphisms within populations in traits as diverse as mimetic wing coloration in butterflies, mating strategies in birds, and malarial susceptibility in mosquitoes. A large supergene also underlies variation in social organization in Formica ants. Alternative supergene haplotypes are associated with the presence of either a single queen (monogyny) or multiple queens (polygyny) within colonies. Here, we assess the social structure and supergene status of the North American species Formica neoclara.ResultsWe sequenced a subset of the genome in 280 individuals sampled in populations from California to northern British Columbia using ddRADseq. We determined that F. neoclara is socially polymorphic in queen number, and we show that the social polymorphism is associated with alternative haplotypes at the social supergene. Intriguingly, polygyne colonies can harbor workers that are homozygous for both haplotypes as well as heterozygotes.ConclusionsThis colony genetic composition contrasts with other Formica species, in which almost all individuals in polygyne colonies have the polygyne-associated haplotype. The social polymorphism is present in widely distributed and genetically subdivided populations of F. neoclara. In studying this system in F. neoclara, we expand our understanding of the functional evolution of supergene haplotypes as they diverge in different lineages.

Revisiting the components of Macroscelidea social systems: Evidence for variable social organization, including pair‐living, but not for a monogamous mating system

AbstractElephant‐shrews (Macroscelidea) have long been considered the only mammalian order to be completely monogamous, based on observations of their pair‐living social organization. We reviewed primary studies on the four components of social systems (social organization, mating system, social structure, and care system) in elephant‐shrews to evaluate whether they truly are monogamous. To identify gaps in our knowledge of their social system, we reviewed evidence for a pair‐living social organization, mate fidelity (mating system), pair bonds (social structure), and biparental care (care system). Field data were available for eight species and seven were often pair‐living. However, these seven species exhibited intra‐specific variation in social organization; two of these species were also solitary living, two species were also group‐living, and the remaining three species were both solitary and group‐living. The eighth species was exclusively solitary. We reconstructed the ancestral social organization of Macroscelidea using Bayesian phylogenetic mixed‐effects models and found that variable social organization, rather than exclusive pair‐living, was the most likely ancestral state, though there was high uncertainty. No socio‐ecological factors (body size, population density, and habitat) predicted a specific social organization. Observations of mating have been rare, such that no firm statements can be made. However, one unpublished study indicated high levels of extra‐pair paternity. Regarding social structure, there was no evidence of pair‐bonding, but there was evidence of mate guarding. Only maternal care has been observed, with females having very short nursing bouts. Evidence suggests that despite having often a pair‐living form of social organization, Macroscelidea should not be described as a monogamous order, as little or no evidence supports that designation, nor are they exclusively pair‐living (social organization) and we urge further field studies on Macroscelidea social systems.

Females of solitary- and group-living sister species of African striped mice show a similar social structure following experimentally imposed group-living

Social systems vary within and between species, ranging along a continuum between solitary-living to complex societies. Social systems are emergent properties of interactions between individuals, and these interactions are often modulated by hormones. We investigated the behavioral and hormonal consequences of experimentally imposed social grouping in two sister species of the African striped mouse Rhabdomys, one of which (R. pumilio) is group-living in its natural xeric environment, while the other (R. dilectus) is solitary-living in its mesic environment. We compared social behavior of triads of age-matched, unfamiliar females of each species, and measured their serum corticosterone and testosterone concentrations in comparison to solitarily housed controls. On day 1, triads of both species displayed mainly amicable behavior. Aggression was rare, but R. pumilio females showed more aggression than R. dilectus females. Triads of both species shared nests from day 2 onwards, and amicable behavior increased over time. Neither species differed in hormonal concentration compared to their solitary controls, but R. dilectus had 1.3 × higher serum corticosterone than R. pumilio. Serum testosterone did not differ between species or treatments. Neither corticosterone nor testosterone concentration measured at the end of the experiment was related to the duration of amicable behavior shown between triad members at the end of the study. Both species established a similar social structure when housed in non-kin triads in captivity. Both displayed high amicability and little aggression, indicating that environmental factors, such as resource distribution and duration of the breeding season, may be more important determinants of social organization in striped mice than social tolerance. Variation in social systems occurs both between and within species, and to date, it is still poorly understood how differences in social tolerance relate to inter-specific variation in social systems. We experimentally imposed social grouping in females of two sister species of the African striped mouse, one naturally group-living and one solitary-living species. We studied interactions between individuals in these experimental groups over 21 days and measured testosterone and corticosterone concentration at the end of the experiment. Both species mainly showed socio-positive behavior and little aggression occurred. Individuals from experimental groups of both species had similar testosterone and corticosterone concentrations compared to solitary-housed control females of the same species. Our results show that both species are tolerant of conspecifics, at least in captivity, indicating that environmental factors might be more important determinants of social organization than social tolerance.

Sett Use, Density and Breeding Phenology of Badgers in Mediterranean Agro-Sylvo-Pastoral Systems.

Simple SummaryUnderstanding carnivores social structure variation is pivotal for properly addressing conservation challenges and solutions. The European badgers is a social carnivore for which most of the available information regarding how this species is socially organized derives from central west populations. This article describes the group composition, den use patterns and breeding phenology of a Mediterranean population of badgers. We showed that badger live in low density, in relatively small groups, composed by 2–4 adult animals and ca. 2 cubs, born in winter. These patterns, representing a variation of what was described for other populations, show that badgers take advantage of the landscape context, where human-related resources and mild environmental conditions allow badger to reach higher densities than in many southern populations, and to reproduce earlier than their northern counterparts.Carnivores social organization varies widely, from strongly social to solitary predators. European badgers are facultative social carnivores that also shows a geographical variation in social structure. These patterns derive mainly from central/west European regions, with an under-representation of Mediterranean populations that face different conservation challenges, especially regarding group composition, sett use patterns and breeding phenology. We addressed these traits topics for a population inhabiting a Portuguese agro-silvo-pastoral system. Based on monthly monitoring of 34 setts and continuous camera-trapping surveys of 12, we showed that setts surrounded by diversified vegetation and located in sandy sites are more used, a pattern probably linked to food availability and ease of sett excavation and maintenance, respectively. Badgers followed a general pattern regarding group size (2–4 adults), but showed an intermediate population density (0.49–0.73 badgers/km2), with values higher than those estimated for other Mediterranean environments, but lower than for central-western populations. This, together with the breeding (November/January) and cub emergence (1.8 cubs/sett; March/April) periods, indicates an ecological adaptation to the landscape context, where human-related resources and mild environmental conditions allow badger to reach higher densities than in many southern populations, and to reproduce earlier than their northern counterparts.

Diversity and Consequences of Social Network Structure in Toothed Whales

Toothed whales (suborder Odontoceti) are highly social, large brained mammals with diverse social systems. In recent decades, a large body of work has begun investigating these dynamic, complex societies using a common set of analytical tools: social network analysis. The application of social network theory to toothed whales enables insight into the factors that underlie variation in social structure in this taxon, and the consequences of these structures for survival, reproduction, disease transmission, and culture. Here, we perform a systematic review of the literature regarding toothed whale social networks to identify broad patterns of social network structure across species, common drivers of individual social position, and the consequences of network structure for individuals and populations. We also identify key knowledge gaps and areas ripe for future research. We recommend that future studies attempt to expand the taxonomic breadth and focus on standardizing methods and reporting as much as possible to allow for comparative analyses to test evolutionary hypotheses. Furthermore, social networks analysis may provide key insights into population dynamics as indicators of population health, predictors of disease risk, and as direct drivers of survival and reproduction.

Dynamic spatial overlap in a solitary subterranean rodent: the Anillaco tuco-tuco (Ctenomys sp.)

Abstract Despite striking diversity in mammalian social behavior, studies of social organization have often dichotomized species by identifying them as either solitary or social (i.e., group living). This tendency has been particularly pronounced for subterranean rodents, the majority of which have long been assumed to be solitary. As a result, variation in social organization has likely been underestimated for these animals, particularly for species in which patterns of space use suggest limited or temporally dynamic opportunities for interactions among conspecifics. Here, we characterize patterns of space use in a population of tuco-tucos (Ctenomys sp.) from Anillaco, La Rioja Province, Argentina. Although these animals have been the subject of extensive research regarding circadian patterns of activity, spatial and social relationships among free-living individuals have not been documented. Analyses of radiotelemetry data from 17 individuals monitored during the breeding season (December 2015) revealed that partial overlap of individual home ranges was common, occurring between male–female as well as female–female pairs of animals. Spatial relationships, however, were dynamic, with both home range sizes and overlap changing on a daily basis. Although members of the study population did not meet the criteria typically used to identify group living in subterranean species, they were not completely solitary. Instead, the animals displayed an intermediate form of social organization characterized by persistent partial overlap of the areas occupied by different adults. These data add to the growing comparative picture of social variation in Ctenomys and suggest that further studies of these animals should contribute to improved understanding of the factors underlying differences in mammalian social systems.

Social organization variation and behavioural flexibility in the facultative cleaning goby Elacatinus prochilos

Social species often show intraspecific variation in the size and composition of their social units, i.e. the social organization. This variation represents a challenge for comparative studies trying to understand evolutionary transitions in social organization complexity. Most studies on intraspecific variation in social organization (IVSO) have focused on the environmental factors selecting for variation in social organization but the mechanisms underlying such variation remain relatively unexplored. Here we investigated the potential mechanisms giving rise to IVSO in the Caribbean cleaning goby Elacatinus prochilos . This small reef fish typically exhibits two types of social organization, pair living or group living, which not only differ in group size but also in feeding strategy and social behaviour. Pair-living gobies cooperatively feed on ectoparasites removed from larger visiting fish, while group-living gobies feed on microinvertebrates living inside sponges and aggressively defend the best feeding spots against each other. We tested how flexible the social organization, social structure and competition over a food source of E. prochilos are by experimentally manipulating group composition, habitat structure and feeding condition of pair-living and group-living wild adult gobies in laboratory. Despite having different original social organizations in the wild, both pair-living and group-living gobies formed dominance hierarchies and exhibited affiliative behaviours in our group manipulations. This indicates that IVSO in this species is not driven by pre-determined or early-developed mechanisms, but rather a consequence of flexibility in social organization, also known as social flexibility. • We investigated the mechanisms of social organization variation in E. prochilos. • We used a controlled group manipulation to test the behavioural flexibility of individuals. • Individuals exhibiting different social organizations in the wild converged in social behaviour. • This indicates that variable social organization is driven by social flexibility.

Modeling social styles in macaque societies applied to a semi-free-ranging group of Macaca tonkeana

The covariation hypothesis (Thierry 2004) describes conflict management and variations in social structure observed in macaque societies and arranges these species in four dominance styles or grades ranging from egalitarian to despotic. Using an agent-based model (i.e., A-KinGDom), we obtained a set of measurements to quantitatively define the four social styles in captive or semi-free-ranging conditions. Results showed that intensity of aggression was an important parameter involved in the emergence of dominance styles and its level was critical to defining grade 2 (i.e., the second of the two despotic grades described in macaques). In our simulations, grade 2 only appeared using high-intensity aggression values that reflected the phylogenetic origin of despotic grades. Moreover, comparison between simulation results and the data obtained on a semi-free ranging group of Macaca tonkeana (classified as grade 4, or egalitarian) showed the presence of traits close to despotic societies (for example, an increase of gradient of hierarchy or a decrease of reconciliation behaviors). These results both support assigning grade 4 to this macaque species according to its phylogenetic origins and indicate the presence of intra-group variability in semi-free ranging groups of macaques, which in turn yields valuable information of their current social structure and facilitate the handling of these groups. We have developed an agent-based model that drives the emergence of social styles in macaque societies. The results of our simulations suggest that social style in macaques is an emergent behavior and that agent-based models are a good tool for exploring emergent behaviors in silico. Moreover, these models can be used to assess hypotheses on social structure in macaque in semi-free-ranging conditions and report useful knowledge about specific techniques for group handling.

Variation of social strategies within and between individual black-tailed prairie dogs (Cynomys ludovicianus) during the reproductive season

Sociality describes the tendency for members of a species to associate in a group based on social attraction. To balance the trade-offs of sociality, the fitness consequences (and therefore proclivity towards being social) should be expected to vary across individuals and within the same individual, across time. We used social network analysis to evaluate the causes and consequences of within- and between-individual variation in sociality in a wild population of black-tailed prairie dogs (Cynomys ludovicianus) during the reproductive season. We hypothesised that individuals would adjust their behaviours based on a key life-history event: reproduction. We assessed this variation by comparing differences in social behaviour between individuals in different life history stages and within individuals across the reproductive season. We predicted breeding females would increase their agonistic interactions to protect their offspring from infanticide during reproduction, while non-reproductive individuals would increase their affiliative interactions to maintain stability in their social network and increase their indirect fitness. We found that the number of social interactions decreased after reproduction for all individuals. Breeding females did not increase their agonistic interactions compared to other groups, but instead had overall decreased social interactions during reproduction, which corresponded with increased fitness. For non-breeding females, an increase of affiliative social interactions correlated with increased indirect fitness as we predicted. Our multiple-level, temporally structured analyses revealed under-realised complexities regarding within- and between-individual variation in social interactions, suggesting reproductive status dictates different social strategies to optimise fitness. Social living with conspecifics confers a range of costs and benefits, the trade-offs of which are expected to change based on life history. Therefore, individuals should modulate their sociality across life history transitions to optimise fitness. Reproductive status is known to affect socio-behavioural decisions across taxa. We used a highly social species, black-tailed prairie dogs, to investigate variation in social structure across the reproductive season, and understand both the causes and consequences of individual variation in social structure. Prairie dogs offered easily observable, dynamic social behaviours and quantifiable fitness consequences to truly demonstrate acute social change. Our results suggest that there is variation of social interactions not only within individuals over time, but also between reproductive groups in the same time period. Our analyses suggest that social variation has important consequences for fitness and should further stimulate study of temporally based analyses of social behaviour.

Age Set vs. Kin: Culture and Financial Ties in East Africa

We study how social organization shapes patterns of economic interaction and the distributional consequences of public policy, focusing on the distinction between age-based and kin-based social structure in sub-Saharan Africa. In age-based ethnicities, known as ``age set societies,'' individuals are organized into social groups based on age cohort that take priority over kinship ties. Motivated by ethnographic accounts that suggest that these differences are important for financial transfers, we analyze an unconditional cash transfer program in Kenya and document that in age set societies there are large consumption spillovers within the age cohort, but not the extended family, while in kin-based societies we find the opposite pattern. Next, we document that local variation in social structure shapes the impact of national policy. Exploiting the staggered roll-out of Uganda's social pension program, we find that household exposure to the program has large, positive effects on child nutrition and educational investment in kin-based societies, but no impact on children in age set societies, where intergenerational ties are weak.