Mainstreaming the social sciences in conservation

Despite broad recognition of the value of social sciences and increasingly vocal calls for better engagement with the human element of conservation, the conservation social sciences remain misunderstood and underutilized in practice. The conservation social sciences can provide unique and important contributions to society's understanding of the relationships between humans and nature and to improving conservation practice and outcomes. There are 4 barriers—ideological, institutional, knowledge, and capacity—to meaningful integration of the social sciences into conservation. We provide practical guidance on overcoming these barriers to mainstream the social sciences in conservation science, practice, and policy. Broadly, we recommend fostering knowledge on the scope and contributions of the social sciences to conservation, including social scientists from the inception of interdisciplinary research projects, incorporating social science research and insights during all stages of conservation planning and implementation, building social science capacity at all scales in conservation organizations and agencies, and promoting engagement with the social sciences in and through global conservation policy‐influencing organizations. Conservation social scientists, too, need to be willing to engage with natural science knowledge and to communicate insights and recommendations clearly. We urge the conservation community to move beyond superficial engagement with the conservation social sciences. A more inclusive and integrative conservation science—one that includes the natural and social sciences—will enable more ecologically effective and socially just conservation. Better collaboration among social scientists, natural scientists, practitioners, and policy makers will facilitate a renewed and more robust conservation. Mainstreaming the conservation social sciences will facilitate the uptake of the full range of insights and contributions from these fields into conservation policy and practice.     

Evolving social influence in large populations

Darwinian studies of collective human behaviour, which deal fluently with change and are grounded in the details of social influence among individuals, have much to offer “social” models from the physical sciences which have elegant statistical regularities. Although Darwinian evolution is often associated with selection and adaptation, “neutral” models of drift are equally relevant. Building on established neutral models, we present a general, yet highly parsimonious, stochastic model, which generates an entire family of real-world, right-skew socio-economic distributions, including exponential, winner-take-all, power law tails of varying exponents, and power laws across the whole data. The widely used Barabási and Albert (1999) Science 286: 509-512 “B-A” model of preferential attachment is a special case of this general model. In addition, the model produces the continuous turnover observed empirically within these distributions. Previous preferential attachment models have generated specific distributions with turnover using arbitrary add-on rules, but turnover is an inherent feature of our model. The model also replicates an intriguing new relationship, observed across a range of empirical studies, between the power law exponent and the proportion of data represented in the distribution.     

Potential banana skins in animal social network analysis

Social network analysis is an increasingly popular tool for the study of the fine-scale and global social structure of animals. It has attracted particular attention by those attempting to unravel social structure in fission–fusion populations. It is clear that the social network approach offers some exciting opportunities for gaining new insights into social systems. However, some of the practices which are currently being used in the animal social networks literature are at worst questionable and at best over-enthusiastic. We highlight some of the areas of method, analysis and interpretation in which greater care may be needed in order to ensure that the biology we extract from our networks is robust. In particular, we suggest that more attention should be given to whether relational data are representative, the potential effect of observational errors and the choice and use of statistical tests. The importance of replication and manipulation must not be forgotten, and the interpretation of results requires care. This contribution is part of the special issue “Social Networks: new perspectives” (Guest Editors: J. Krause, D. Lusseau and R. James).     

Quantifying social synergy in insect and human societies

What are the benefits of society? What are the adaptive advantages of social behavior? The fact that societies exist suggest that society favors synergies in the interactions between individuals. One such synergy or adaptive advantage might be the increased efficiency in the use of scarce resources. This has been postulated to occur in the “metabolic scaling law”, where larger organisms with more cells consume less energy per unit mass than smaller organisms. Here, I develop a similar scale-free index for social synergy applicable to energy consumption, and apply it to social insect colonies and human cities. The results show that all societies studied increase the efficiency of energy consumption with increased sizes. This study shows that social synergy is reliably quantifiable and that its increase with size is much larger in social insects than that observed with the metabolic scaling law in organisms. This allows for the first time to compare quantitatively very different societies, permitting novel studies in social dynamics, for example, the study shows that termite colonies achieve much higher social synergy than ant and honey bee colonies and that Brazilian cities achieve more social synergy than Danish or North American ones, posing new intriguing questions.     

Kin conflict over caste determination in social Hymenoptera

We argue that caste determination, the process whereby females in the social Hymenoptera develop into either queens or workers, is subject to kin-selected conflict. Potential conflict arises because developing females are more closely related to their would-be offspring than to those of other females. Therefore, they may favour becoming queens contrary to the interests of other developing females and of existing queens and workers. We suggest two contexts leading to potential caste conflict. The first occurs when queens are reared in a reproductive phase following an ergonomic phase of worker production, while the second occurs when queens and workers are reared simultaneously. The first context assumes that workers' per capita contribution to colony survival and productivity falls with rising colony size. A critical feature influencing whether potential conflict is realized is the extent to which developing females can determine their own caste (“self-determination”). Self-determination is facilitated when female larvae control their own food intake and when queen-worker size dimorphism is low. We know of no strong evidence for actual conflict over caste fate arising in the first context. However, stingless bees and polygynous ants with excess queen-potential larvae that are either forced to develop as workers or are culled as adults demonstrate actual caste conflict in the second context. Caste conflict does not preclude caste regulation for “the good of the colony”, but such regulation is contingent on either the absence of potential conflict or on developing females losing control of their caste fate. Received: 22 March 1999 / Received in revised form: 15 June 1999 / Accepted: 19 June 1999     

Comparative social network analysis in a leaf-roosting bat

Even though social network analysis provides an important tool to characterize and compare societies, no studies have used its analytical applications to characterize patterns of sociality in bats. Here I use social network analysis to characterize and compare patterns of sociality between three populations of the leaf-roosting bat Thyroptera tricolor. Sites differed in the density of furled leaves used by T. tricolor for roosting. Finca had more leaves per hectare (77), followed by Ureña (58), and Esquinas (7). The time period over which the probability of association is halved based on fitted models was 1,086 days for Finca, 714 days for Ureña, and 303 days for Esquinas. Finca and Ureña had very similar network topologies, with several small clusters, high-clustering coefficients, short path lengths, low node betweenness, and high network robustness. Social networks at Esquinas were composed of one large cluster and several small isolated ones. Esquinas also had high-clustering coefficients, but path length and node betweenness were high. Network resilience was lower in Esquinas compared to Finca and Ureña. These results show that, unlike many other forest-dwelling bats that switch roosts regularly, T. tricolor does not exhibit a typical fission–fusion social system, and that resource availability seems to affect social networks in this bat. In addition, this study highlights the importance of emigrating individuals in maintaining social cohesion, establishing network connectedness, and determining network robustness.     

What drives flexibility in primate social organization?

The importance of behavioral flexibility for understanding primate ecology and evolutionary diversity is becoming increasingly apparent, and yet despite the abundance of long-term studies across diverse sampling localities, we still do not understand the myriad factors responsible for among-site variation in species’ social organization. The goals of our study were to address this question via three main objectives: to quantify social organization flexibility (i.e., across-site intraspecific variation) of well-studied primate species, test the idea that closely related species exhibit similar levels of flexibility, and test hypotheses explaining variation in social organization flexibility among primate species. We obtained data for a total of 175 study sites from 32 primate species representing all major primate clades. We employed phylogenetic principal components analysis to quantify social organization flexibility for each species. We quantified the phylogenetic signal in social organization flexibility and then evaluated the best predictors of flexibility. We found that mean group size was positively related to social organization flexibility. Large social groups may be more flexible because the foraging costs and predation risk associated with adding or subtracting individuals are lower compared to small social groups. There was some support that absolute brain size and the presence of fission–fusion dynamics were also related to high levels of social organization flexibility, suggesting that cognitive ability and/or within-site behavioral flexibility may also lead to increased variation across sites. Our results serve as an early step in understanding the patterns and processes related to social organization flexibility in primates and other social mammals.     

Colony fission affects kinship in a social insect

Establishment of new groups is an important step in the life history of a social species. Fissioning is a common mode not only in group proliferation, for instance, as a regular part of the life cycle in the honey bee, but also when multiple females reproduce in the same group, as in multiple-queen ant societies. We studied the genetic consequences of fissioning in the ant Proformica longiseta, based on DNA microsatellites. In P. longiseta, new nests arise by fissioning from the old ones when they grow large, and the daughter nests consist of workers and queens or queen pupae but never both. Our results show that fissioning is not entirely random with respect to kinship. Workers tend to segregate along kin lines, but only when the initial relatedness in the parental nests is low. Workers in a daughter nest also tend to be associated with closely related adult queens, whereas such an association is not detected between workers and queen pupae. Most queens and workers are carried to the daughter nest by a specialized group of transporting workers, suggesting active kin discrimination by them. Fissioning pattern in P. longiseta is different from that found in other social insects with regular fission (e.g., the honey bee, swarm-founding wasps), where no fissioning along kin lines has been found. It does, however, resemble fissioning in another group of social animals: primates.     

On sustainability and social welfare

This paper proposes to define sustainability in terms of leaving it possible for future generations to sustain certain defined targets. It is shown that variants of genuine savings and the ecological footprint can then serve as indicators of sustainability. The link between sustainability and intergenerational welfare is examined, and it is shown how to incorporate indicators of sustainability into a social welfare measure, including risk in the analysis.     

Ecology,feeding competition and social structure in baboons

Predictions of the model of van Schaik (1989) of female-bonding in primates are tested by systematically comparing the ecology, level of within-group contest competition for food (WGC), and patterns of social behaviour found in two contrasting baboon populations. Significant differences were found in food distribution (percentage of the diet from clumped sources), feeding supplant rates and grooming patterns. In accord with the model, the tendencies of females to affiliate and form coalitions with one another, and to be philopatric, were strongest where ecological conditions promoted WGC. Group fission in the population with strong WGC was “horizontal” with respect to female dominance rank, and associated with female-female aggression during a period of elevated feeding competition. In contrast, where WGC was low, females’ grooming was focused on adult males rather than other females. Recent evidence suggests that group fission here is initiated by males, tends to result in the formation of one-male groups, and is not related to feeding competition but to male-male competition for mates. An ecological model of baboon social structure is presented which incorporates the effects of female-female competition, male-male competition, and predation pressure. The model potentially accounts for wide variability in group size, group structure and social relationships within the genus Papio. Socio-ecological convergence between common baboons and hamadryas baboons, however, may be limited in some respects by phylogenetic inertia. Received: 22 April 1994/Accepted after revision: 9 December 1995     

Plasticity of social organization in a forest ant species

We manipulated availability of food and nesting sites in one population of the forest ant Myrmica punctiventris. The manipulations produced significant changes in relatedness structure, reproductive allocation, and response to hierarchical selection. Food availability appeared to have a consistently stronger influence on these aspects of social organization than did availability of nesting sites. We interpret our experimental results in light of observed differences between populations, and discuss implications for kin selection dynamics. Received: 30 July 1998 / Accepted after revision: 31 October 1998     

Intraspecific comb usurpation in the social wasp Polistes fuscatus

Summary Incidents of usurpation were observed in colonies of Polistes fuscatus nesting on farm buildings (1977–79) and in nestboxes (1980–84) in Johnson County, Iowa, USA. Most usurpations (84.8%) occurred in the latter half of the preworker phase of the colony cycle, which coincided with periods of high predation of combs by vertebrates. Usurpers were probably displaced single foundresses which did not join neighbors or refound colonies after comb loss. Most (89–100%) usurpers of known relatedness to the foundresses they replaced were cousins or less related to them. Usurpation was a significant source of nest loss (19.6%) among single foundresses, but was rare (2.2%) in multiple-foundress colonies and colonies with workers (3.5%). Usurpers often destroyed younger brood (eggs and larvae in instars 1–3) in host colonies, while older larvae and pupae were usually spared. Brood destruction was more pronounced in more advanced host combs. Usurper survivorship after workers eclosed was lower than than of queenright single foundresses (61.5% vs 87.0%). Reproductive success by usurpers was less than that of queenright single foundresses, but greater than that of foundresses which initiated colonies late in the preworker colony cycle.     

Chemical mimicry in an incipient leaf-cutting ant social parasite

Some social parasites of insect societies are known to use brute force when usurping a host colony, but most use more subtle forms of chemical cheating either by expressing as few recognition cues as possible to avoid being recognized or by producing similar recognition cues to the host to achieve positive discrimination. The former “chemical insignificance” strategy represents a more general adaptive syndrome than the latter “chemical mimicry” strategy and is expected to be characteristic of early evolutionary stages of social parasitism. We tested this hypothesis by experimentally analyzing the efficiency by which Acromyrmex echinatior leaf-cutting ants recognize intruding workers of the incipient social parasite Acromyrmex insinuator. The results were consistent with the parasite being “chemically insignificant” and not with the “chemical mimicry” hypothesis. Gas chromatography–mass spectrometry analysis of cuticular hydrocarbon profiles showed that social parasite workers produce significantly fewer hydrocarbons overall and that their typical profiles have very low amounts of hydrocarbons in the “normal” C29–C35 range but large quantities of unusually heavy C43–C45 hydrocarbons. This suggests that the C29–C35 hydrocarbons are instrumental in normal host nestmate recognition and that the C43–C45 compounds, all of which are dienes and thus more fluid than the corresponding saturated compounds, may reinforce “chemical insignificance” by blurring any remaining variation in recognition cues.