Communal nesting and kinship in degus (<Emphasis Type="Italic">Octodon degus</Emphasis>)

Communal nesting is a fundamental component of many animal societies. Because the fitness consequences of this behavior vary with the relatedness among nest mates, understanding the kin structure of communally nesting groups is critical to understanding why such groups form. Observations of captive degus (Octodon degus) indicate that multiple females nest together, even when supplied with several nest boxes. To determine whether free-living degus also engage in communal nesting, we used radiotelemetry to monitor spatial relationships among adult females in a population of O. degus in central Chile. These analyses revealed that females formed stable associations of > 2–4 individuals, all of whom shared the same nest site at night. During the daytime, spatial overlap and frequency of social interactions were greatest among co-nesting females, suggesting that nesting associations represent distinct social units. To assess kinship among co-nesting females, we examined genotypic variation in our study animals at six microsatellite loci. These analyses indicated that mean pairwise relatedness among members of a nesting association (r=0.25) was significantly greater than that among randomly selected females (r=–0.03). Thus, communally nesting groups of degus are composed of female kin, making it possible for indirect as well as direct fitness benefits to contribute to sociality in this species.     

Monogamy in large bee societies: a stingless paradox

High genetic diversity is important for the functioning of large insect societies. Across the social Hymenoptera (ants, bees, and wasps), species with the largest colonies tend to have a high colony-level genetic diversity resulting from multiple queens (polygyny) or queens that mate with multiple males (polyandry). Here we studied the genetic structure of Trigona spinipes, a stingless bee species with colonies an order of magnitude larger than those of polyandrous honeybees. Genotypes of adult workers and pupae from 43 nests distributed across three Brazilian biomes showed that T. spinipes colonies are usually headed by one singly mated queen. Apart from revealing a notable exception from the general incidence of high genetic diversity in large insect societies, our results reinforce previous findings suggesting the absence of polyandry in stingless bees and provide evidence against the sperm limitation hypothesis for the evolution of polyandry. Stingless bee species with large colonies, such as T. spinipes, thus seem promising study models to unravel alternative mechanisms to increase genetic diversity within colonies or understand the adaptive value of low genetic diversity in large insect societies.     

Inbreeding and the evolution of sociality in arthropods

Animals have evolved strategies to optimally balance costs and benefits of inbreeding. In social species, these adaptations can have a considerable impact on the structure, the organization, and the functioning of groups. Here, we consider how selection for inbreeding avoidance fashions the social behavior of arthropods, a phylum exhibiting an unparalleled richness of social lifestyles. We first examine life histories and parental investment patterns determining whether individuals should actively avoid or prefer inbreeding. Next, we illustrate the diversity of inbreeding avoidance mechanisms in arthropods, from the dispersal of individuals to the rejection of kin during mate choice and the production of unisexual broods by females. Then, we address the particular case of haplodiploid insects. Finally, we discuss how inbreeding may drive and shape the evolution of arthropods societies along two theoretical pathways.     

Surprising cooperation despite apparently irreconcilable differences: Agricultural water use efficiency and CALFED

Much has been said about the need and benefits of consensus building for resolving disagreements about water and environmental management. Less has been said about how to better convene and facilitate those processes. This paper focuses on the latter, examining the challenges and breakthroughs encountered when decision-makers convene consensus building processes that seek an agreement among stakeholders who believe they have “apparently irreconcilable differences.” The research described here analyzes two multi-stakeholder, collaborative processes convened by the CALFED Bay-Delta Program (CALFED) on the issue of agricultural water use efficiency in the Sacramento and San Joaquin river watersheds of California. The first process made very little progress; however, stakeholder representatives in the second were able to forge an agreement that included significant innovation and surprising risk taking by all sides. Analyzing the two processes, this paper shows that the stakeholders, conveners, and facilitators in these processes had to do much more than make the discrete trades across interests envisioned in consensus building theory or reframing as described in theories about conflict and frames. Looking at the data, this paper shows how several concepts from outside consensus building—including boundary objects and interlanguage—along with less well-known concepts and issues within the consensus building literature—bricolage and representation—can provide insights into how the Steering Committee accomplished what it did. This paper introduces these additional concepts, how they mattered in this CALFED process, and suggests a complex set of interrelated insights into how future collaborative and integrative environmental programs can approach the most difficult environmental policy and management conflicts.     

Regulation of sexual development in the basal termite Cryptotermes secundus: mutilation, pheromonal manipulation or honest signal?

Social insect colonies are not the harmonious entities they were once considered. Considerable conflicts exist between colony members, as has been shown for Hymenoptera. For termites, similar studies are lacking, but aggressive manipulations have been claimed to regulate sexual development, and even to account for the evolution of workers. This study on a basal termite, Cryptotermes secundus (Kalotermitidae), suggests that the importance of aggressive manipulations in termites has been overemphasized. Wing-bud mutilations, a means proposed to regulate the development of dispersing sexuals (alates), seem to be artifacts of handling conditions that cause disturbance. Aggressive behaviors never occurred unless colonies were disturbed. Theoretical considerations further showed that the potential for intense conflict among termite nestmates is low compared to hymenopteran societies. Strong conflicts are only expected to occur over the replacement of natal reproductives that died, while less intense conflicts should exist over the development into alates when food in the colony becomes limiting. Accordingly, intracolonial aggressive interactions over replacement are common, whereas nestmates seem to manipulate alate development via proctodeal feeding when food resources decline. However, the latter is rather an honest signal than a manipulation because only the most competent prospective dispersers can impede the development of nestmates.     

Growth and social behavior in a cichlid fish are affected by social rearing environment and kinship

Living in groups is a widespread phenomenon in many animal taxa. The reduction of predation risk is thought to be an important cause for the formation of groups. Consequently, grouping behavior is particularly pronounced during vulnerable life stages, i.e., as juveniles. However, group living does not only provide benefits but also imposes costs on group members, e.g., increased competition for food. Thus, benefits of grouping behavior might not be evident when predation risk is absent. The adaptive significance of living and also developing in a group independent from predation risk has received relatively little attention although this might have important implications on the evolution and maintenance of group living. The first aim of the present study was to examine whether the social environment affects juvenile performance in the cichlid fish Pelvicachromis taeniatus and, secondly, whether kinship affects social behavior. Kin selection theory predicts benefits from grouping with kin. Here, we demonstrate that juveniles reared in a group grow on average faster compared to juveniles reared in isolation under standardized laboratory conditions without predation risk. Furthermore, we found significant differences in social behavior between juveniles reared in a group and reared in isolation. Fish reared in isolation were significantly more aggressive and less willing to shoal than group-reared fish. As expected, genetic relatedness influenced social behavior in group-reared fish as well: dyads of juveniles consisting of kin showed increased group cohesiveness compared to non-kin dyads. We discuss the potential benefits of group living in general and living with kin in particular.     

Who should do what in environmental management? Twelve principles for allocating responsibilities

In environmental management there is often discussion on the allocation of responsibilities. Such discussions can continue for a long time and can form an obstacle for effective action. In this article twelve normative principles for the allocation of responsibilities are identified, coming from three different sources: the arguments used in discussions on responsibilities, Dutch and European law, and the environmental management literature. The principles are (1) capacity, (2) lowest social costs, (3) causation, (4) interest, (5) scale, (6) subsidiarity, (7) structural integration, (8) separation, (9) solidarity, (10) transparency, (11) stability (but not standstill), and (12) acquired rights. These principles point to fundamental tensions in environmental management and sometimes conflict with each other. At the same time they may help to resolve conflicts by providing common points of reference that are independent from the often conflicting interests of the discussants.     

Absence of within-colony kin discrimination: foundresses of the social wasp, Polistes carolina, do not prefer their own larvae

 There is great potential for conflict within social insect colonies especially when there are multiple inseminated females laying eggs. One reason that conflict is not always realized may be that these females do not identify their own progeny and direct their attentions preferentially towards them. Using DNA microsatellite loci we were able to determine exactly which female was the mother of each larva in eight nests of the social wasp, Polistes carolina. Using 26 h of videotapes of natural nests we observed 2,093 feedings of specific larvae by these adults and found that they did not preferentially feed their own progeny. Instead feedings were distributed to progeny as predicted based on their frequency in the nest. The absence of nepotism towards closest kin within colonies in this system is likely to promote colony harmony. Received: 24 January 2000 / Accepted in revised form: 30 March 2000     

Irregular brood patterns and worker reproduction in social wasps

The potential for reproductive conflict among colony members exists in all social insect societies. For example, queens and workers may be in conflict over the production of males within colonies. Kin selection theory predicts that in a colony headed by a multiply-mated queen, worker reproduction is prevented by worker policing in the form of differential oophagy. However, few studies have demonstrated that workers actually lay eggs within queenright colonies. The purpose of this study was to determine if workers laid male eggs within unmanipulated queen-right colonies of the polyandrous social wasps Vespula maculifrons and V. squamosa. We focused our analysis on an unusual brood pattern within colonies, multiple egg cells. We were primarily interested in determining if individuals reared in these irregular circumstances were queen or worker offspring. To address this question, we genotyped 318 eggs from eight V. maculifrons and two V. squamosa colonies. No worker‑reproduction was detected in any of the queenright colonies; all of the eggs found in multiple egg cells were consistent with being queen‑produced. However, the frequency of multiple egg cells differed among colonies, suggesting that queens vary in the frequency of errors they make when laying eggs within cells. Finally, we suggest that workers may not be laying eggs within queenright colonies and that worker reproduction may be controlled through mechanisms other than differential oophagy in polyandrous Vespula wasps.     

The alternative Pharaoh approach: stingless bees mummify beetle parasites alive

Workers from social insect colonies use different defence strategies to combat invaders. Nevertheless, some parasitic species are able to bypass colony defences. In particular, some beetle nest invaders cannot be killed or removed by workers of social bees, thus creating the need for alternative social defence strategies to ensure colony survival. Here we show, using diagnostic radioentomology, that stingless bee workers (Trigona carbonaria) immediately mummify invading adult small hive beetles (Aethina tumida) alive by coating them with a mixture of resin, wax and mud, thereby preventing severe damage to the colony. In sharp contrast to the responses of honeybee and bumblebee colonies, the rapid live mummification strategy of T. carbonaria effectively prevents beetle advancements and removes their ability to reproduce. The convergent evolution of mummification in stingless bees and encapsulation in honeybees is another striking example of co-evolution between insect societies and their parasites.     

The structure of stereotyped calls reflects kinship and social affiliation in resident killer whales (Orcinus orca)

A few species of mammals produce group-specific vocalisations that are passed on by learning, but the function of learned vocal variation remains poorly understood. Resident killer whales live in stable matrilineal groups with repertoires of seven to 17 stereotyped call types. Some types are shared among matrilines, but their structure typically shows matriline-specific differences. Our objective was to analyse calls of nine killer whale matrilines in British Columbia to test whether call similarity primarily reflects social or genetic relationships. Recordings were made in 1985–1995 in the presence of focal matrilines that were either alone or with groups with non-overlapping repertoires. We used neural network discrimination performance to measure the similarity of call types produced by different matrilines and determined matriline association rates from 757 encounters with one or more focal matrilines. Relatedness was measured by comparing variation at 11 microsatellite loci for the oldest female in each group. Call similarity was positively correlated with association rates for two of the three call types analysed. Similarity of the N4 call type was also correlated with matriarch relatedness. No relationship between relatedness and association frequency was detected. These results show that call structure reflects relatedness and social affiliation, but not because related groups spend more time together. Instead, call structure appears to play a role in kin recognition and shapes the association behaviour of killer whale groups. Our results therefore support the hypothesis that increasing social complexity plays a role in the evolution of learned vocalisations in some mammalian species.     

Indigenous people and co-management: implications for conflict management

Co-management agreements among indigenous people, state agencies, and other stakeholders offer substantial promise as a way of dealing with natural resource conflicts in a participatory and equitable manner. However, experience shows that co-management regimes can set into motion new conflicts or cause old ones to escalate. In practice the result may not be power sharing but rather a strengthening of the state's control over resource policy, management, and allocation. Instead of contributing to local empowerment, such arrangements may further marginalize communities and resource users. We use case material, primarily from northern Canada and South Asia, to explore the pervasive role of conflict in generating, shaping, and influencing the performance of co-management regimes. The paper analyzes the divergent interests and motives of state agencies in planning and implementing co-management arrangements. It highlights the cultural, political, and legal obstacles encountered by indigenous people and other rural communities in trying to negotiate co-management arrangements. We also explore the conflicts that can arise in co-management regimes where local participation in decision making is very limited. General lessons and recommendations are drawn from our analysis.     

The San Francisco Bay-Delta: A failure of decision-making capacity

The paper reviews the history of Bay-Delta decision-making in California in order to highlight the continuity between what happened with CALFED and what happened in the preceding decades since water project deliveries began in 1949. Throughout this period, there has been intense conflict about whether and how to transfer water from the Bay-Delta to users elsewhere—a conflict marked by a fundamental opposition of interests among stakeholders. We document how the State of California has failed to organize itself effectively to resolve this conflict and make a decision on how to manage the Delta. The strategy consistently adopted by the State was to encourage the main parties – agricultural and urban water diverters, and fisheries and other instream-protection interests – to work out a solution among themselves, rather than imposing one externally. However, economic theory suggests that a bargaining solution is unlikely to exist because of the extreme opposition of interest among the parties. The Bay-Delta history amply confirms this theoretical prediction. Thus, the State's strategy of relying on voluntary agreement to resolve the issue is fundamentally misconceived and is, at some level, an abdication of its responsibility.     

Relatedness communicated in lemur scent

Lemurs are the most olfactory-oriented of primates, yet there is still only a basic level of understanding of what their scent marks communicate. We analyzed scent secretions from Milne-Edwards' sifakas (Propithecus edwardsi) collected in their natural habitat of Ranomafana National Park, Madagascar. We sought to test whether the scent mark could signal genetic relatedness in addition to species, sex, season, and individuality. We not only found correlations (r ²?=?0.38, P?=?0.017) between the total olfactory fingerprint and genetic relatedness but also between relatedness and specific components of the odor, despite the complex environmental signals from differences in diet and behavior in a natural setting. To the best of our knowledge, this is the first demonstration of an association between genetic relatedness and chemical communication in a wild primate population. Furthermore, we found a variety of compounds that were specific to each sex and each sampling period. This research shows that scent marks could act as a remote signal to avoid inbreeding, optimize mating opportunities, and potentially aid kin selection.     

Exploring tensions and conflicts in invasive species management: The case of Asian carp

There is a growing recognition that scientific and social conflict pervades invasive species management, but there is a need for empirical work that can help better understand these conflicts and how they can be addressed. We examined the tensions and conflicts facing invasive Asian carp management in Minnesota by conducting 16 in-depth interviews with state and federal agency officials, academics, and stakeholders. Interviewees discussed the tensions and conflicts they saw impacting management, their implications, and what could be done to address them. We found three key areas of conflict and tension in Asian carp management: 1) scientific uncertainty concerning the impacts of Asian carp and the efficacy and non-target effects of possible management actions; 2) social uncertainty concerning both the lack of societal agreement on how to respond to Asian carp and the need to avoid acting from apathy and/or fear; and 3) the desired approach to research and management – whether it is informed by “political need” or “biological reality”. Our study of these tensions and conflicts reveals their importance to Asian carp management and to invasive species management, more broadly. We conclude with a discussion of possible ways to address these areas of tension and conflict, including the potential of deliberative, participatory approaches to risk-related decision making and the need to productively engage with apathy and fear.     

基于陆海统筹的陆海经济关系及国土空间利用：现状、问题及发展方向

陆海统筹作为我国重大国家战略,既要在国家层面实现海陆要素的优化配置,更要在区域层面引导海陆产业的空间布局,从而推动区域协调发展。当前基于陆海统筹的陆海经济和国土空间利用研究还处于探索阶段,缺乏系统的理论研究与大量的实践应用。从陆海统筹相关概念及理论、陆海社会经济关系、海岸带空间利用冲突及规划管控三方面,探讨了不同学科学者在陆海统筹背景下的陆海经济关系、国土空间利用研究进展及存在问题,并提出未来研究应强化陆海统筹背景下的陆海资源环境与陆海社会经济发展间的多尺度耦合与带动效应研究,明晰区域陆海统筹水平及演化特征、影响因素及响应机制,重视海岸带空间利用冲突诊断与调控,持续推进基于陆海统筹的海岸带国土空间规划实践。     

Variable virulence among isolates of Ascosphaera apis: testing the parasite–pathogen hypothesis for the evolution of polyandry in social insects

The queens of many eusocial insect species are polyandrous. The evolution of polyandry from ancestral monoandry is intriguing because polyandry undermines the kin-selected benefits of high intracolonial relatedness that are understood to have been central to the evolution of eusociality. An accumulating body of evidence suggests that polyandry evolved from monoandry in part because genetically diverse colonies better resist infection by pathogens. However, a core assumption of the “parasite–pathogen hypothesis”, that there is variation in virulence among strains of pathogens, remains largely untested in vivo. Here, we demonstrate variation in virulence among isolates of Ascosphaera apis, the causative organism of chalkbrood disease in its honey bee (Apis mellifera) host. More importantly, we show a pathogen–host genotypic interaction for resistance and pathogenicity. Our findings therefore support the parasite-parasite hypothesis as a factor in the evolution of polyandry among eusocial insects.     

Kin composition effects on reproductive competition among queenless honeybee workers

Kin selection and inclusive fitness theories predict that, in hopeless queenless (QL) groups, competition or cooperation will occur over male production among workers of different patrilines. Competition is expected to involve mutual inhibition of reproduction and to affect fertility advertisement. To examine kin effect on these phenomena, we studied QL groups of honeybee workers comprising three types of kin structure: groups composed of pure single patrilines, groups composed of three mixed patrilines (all originating from colonies headed by single-drone-inseminated queens), and control groups composed of bees originating from naturally mated queens. Global assessment of ovarian development, irrespective of patriline composition, revealed no differences among group types. In contrast, the performance of specific patrilines revealed that, in the three-mixed-patriline groups, some patrilines were reproductively suppressed compared to their performance when reared as a pure single patriline, resulting in an uneven share of reproduction. Analysis of the fertility signal produced by Dufour's gland revealed kin composition effects, which may reflect the bees' competitive efforts. Although patriline effects on worker reproductive superiority have been shown in QL colonies, we were able to investigate specific patriline performance both in competitive and noncompetitive situations here for the first time. The results are consistent with the hypothesis that reproductive and pheromonal competitions in QL groups are affected by the number of subfamilies populating a colony and that these act as coalitions. The results also emphasize that within-colony heterogeneity, in the form of multiple patrilines, has far-reaching consequences on social evolution.     

Potential application of mediation to land use conflicts in small-scale mining

Small-scale or artisanal mining is a poverty-driven activity found mainly in remote areas of developing nations. It routinely generates land use conflicts with other stakeholders, primarily large mining companies. The scale of these disputes (occasionally involving armed conflict) is usually sufficient to have significant adverse impacts on the natural environment and the local population. After describing the small-scale mining sector, this paper outlines the characteristics, causes and costs of the land use conflicts with which this activity is often associated. It then discusses some of the more common initiatives that have been taken, primarily by mining companies, to attempt to manage these disputes. Since these approaches are incapable of fully reconciling the range of stakeholder’s interests involved in these conflicts, mediation is proposed as an effective mechanism to achieve their resolution. After an overview of mediation and its potential advantages, the need to apply this process to these disputes is established. Despite its advantages and considerable potential in this application, mediation is not a panacea for resolving all land use conflicts. Based on an extensive literature review, a set of 19 characteristics of disputes that may increase their amenability to mediation is compiled. By then demonstrating that small-scale mining disputes satisfy most of these criteria, the paper concludes that mediation has sufficient promise in this setting to warrant its experimental use.     

The role of social, political, and economic interests in promoting state green electricity policies

State governments in the United States have adopted a number of policies to encourage the production of electricity from “green” energy sources. While these state-level policies have been shown to stimulate green electricity development, the rate at which such policies have been adopted by the states differs significantly. This paper examines the potential influence of a state's particular social, political, and economic interests on its propensity to adopt green electricity policies. We use an empirical model that combines various social, political and economic indicators as explanatory variables of a state's likelihood to adopt four specific green electricity policies: renewable portfolio standards, net metering rules, public benefits funds, and generation disclosure rules. Using binary logistics regressions, the results suggest that social interests, measured by the level of income, the level of education, and the degree of participation in environmental lobbying groups, are positively linked to the adoption of green electricity policies. Similarly, political interests as measured by the pro-environment voting by states’ representatives in the U.S. Congress, also play a positive role in the adoption of such policies.