|
|
Selva, N., Cortés-Avizanda, A., Lemus, J. A., Blanco, G., Mueller, T., Heinrich, B., et al. Stress associated with group living in a long-lived bird. Biol Lett, .
Abstract: Many long-lived avian species adopt life strategies that involve a gregarious way of life at juvenile and sub-adult stages and territoriality during adulthood. However, the potential associated costs of these life styles, such as stress, are poorly understood. We examined the effects of group living, sex and parasite load on the baseline concentration of faecal stress hormone (corticosterone) metabolites in a wild population of common ravens (Corvus corax). Corticosterone concentrations were significantly higher in non-breeding gregarious ravens than in territorial adults. Among territorial birds, males showed higher stress levels than their mates. Parasite burdens did not affect hormone levels. Our results suggest a key role of the social context in the stress profiles of the two population fractions, and that group living may be more energetically demanding than maintaining a territory. These findings have implications for understanding hormonal mechanisms under different life styles and may inspire further research on the link between hormone levels and selective pressures modulating gregarious and territorial strategies in long-lived birds.
|
|
|
|
Levin, L. E. (1996). Passage order through different pathways in groups of schooling fish, and the diversified leadership hypothesis. Behav. Process., 37(1), 1–8.
Abstract: The diversified leadership hypothesis proposes that different individuals within a school of fish act as leaders in different circumstances. This `circumstantial leadership' results from inter-individual behavioral variability and a `cohesion-dispersion' tendency modulated by `failure-success' contingencies. The hypothesis predicts that when offered different pathways to escape the restriction of their swimming space, individuals within a group of fish will show 1. (a) consistent passage orders in each pathway, but2. (b) different passage orders in different pathways. Using an avoidance paddle and three different groups of fish (Aphyocharax erithrurus) the results confirmed prediction 1. (a) while prediction2. (b) was verified only in one group.
|
|
|
|
Connor, R. C., Wells, R. S., Mann, J., & Read, A. J. (2000). The bottlenose dolphin: Social relationships in a fission-fusion society. In J. Mann, R. C. Connor, P. L. Tyack, & H. Whitehead (Eds.), Cetacean Societies: Field Studies of Dolphins and Whales. (pp. 91–126). Chicago: University of Chicago Press.
Abstract: Book Description
“Part review, part testament to extraordinary dedication, and part call to get involved, Cetacean Societies highlights the achievements of behavioral ecologists inspired by the challenges of cetaceans and committed to the exploration of a new world.”-from the preface by Richard Wrangham
Long-lived, slow to reproduce, and often hidden beneath the water's surface, whales and dolphins (cetaceans) have remained elusive subjects for scientific study even though they have fascinated humans for centuries. Until recently, much of what we knew about cetaceans came from commercial sources such as whalers and trainers for dolphin acts. Innovative research methods and persistent efforts, however, have begun to penetrate the depths to reveal tantalizing glimpses of the lives of these mammals in their natural habitats.
Cetacean Societies presents the first comprehensive synthesis and review of these new studies. Groups of chapters focus on the history of cetacean behavioral research and methodology; state-of-the-art reviews of information on four of the most-studied species: bottlenose dolphins, killer whales, sperm whales, and humpback whales; and summaries of major topics, including group living, male and female reproductive strategies, communication, and conservation drawn from comparative research on a wide range of species.
Written by some of the world's leading cetacean scientists, this landmark volume will benefit not just students of cetology but also researchers in other areas of behavioral and conservation ecology as well as anyone with a serious interest in the world of whales and dolphins.
Contributors are Robin Baird, Phillip Clapham, Jenny Christal, Richard Connor, Janet Mann, Andrew Read, Randall Reeves, Amy Samuels, Peter Tyack, Linda Weilgart, Hal Whitehead, Randall S. Wells, and Richard Wrangham.
Keywords: cetacean social behavior, male alliance formation, most cetacean species, platanistid river dolphins, cetacean sociality, strategies and social bonds, female cetaceans, many cetologists, most mysticetes, sperm whale calves, passive fishing nets, variant whistles, historical whaling records, cetacean systematics, stable matrilineal groups, peak calving season, suction cup tags, mutualistic groups, cetacean vocalizations, focal animal studies, larger odontocetes, predictive signaling, individual cetaceans, sperm whale clicks, resident killer whales
|
|
|
|
Mech L.D. (2000). Leadership in Wolf, Canis lupus, Packs. Can Field Nat, 114(2), 259–263.
Abstract: I examine leadership in Wolf (Canis lupus) packs based on published observations and data gathered during summers from 1986 to 1998 studying a free-ranging pack of Wolves on Ellesmere Island that were habituated to my presence. The breeding male tended to initiate activities associated with foraging and travel, and the breeding female to initiate, and predominate in, pup care and protection. However, there was considerable overlap and interaction during these activities such that leadership could be considered a joint function. In packs with multiple breeders, quantitative information about leadership is needed.
Keywords: Wolf, Canis lupus, leadership, behavior, foraging, movements, pup care, provisioning, sociality, reproduction, breeding, Northwest Territories.
|
|
|
|
Creel, S. (2001). Social dominance and stress hormones. Trends. Ecol. Evol, 16(9), 491–497.
Abstract: In most cooperatively breeding birds and mammals, reproductive rates are lower for social subordinates than for dominants, and it is common for reproduction in subordinates to be completely suppressed. Early research conducted in captivity showed that losing fights can increase glucocorticoid (GC) secretion, a general response to stress. Because GCs can suppress reproduction, it has been widely argued that chronic stress might underlie reproductive suppression of social subordinates in cooperative breeders. Contradicting this hypothesis, recent studies of cooperative breeders in the wild show that dominant individuals have elevated GCs more often than do subordinates. The findings that elevated GCs can be a consequence of subordination or a cost of dominance complicate the conventional view of social stress, with broad ramifications for the evolution of dominance and reproductive suppression.
|
|
|
|
Valone, Thomas J., & Templeton, J. J. (2002). Public information for the assessment of quality: a widespread social phenomenon. Phil. Trans. Biol. Sci., 357(1427), 1549–1557.
Abstract: We propose that the use of public information about the quality of environmental resources, obtained by monitoring the sampling behaviour of others, may be a widespread social phenomenon allowing individuals to make faster, more accurate assessments of their environment. To demonstrate this (i) we define public information and distinguish it from other kinds of social information; (ii) we review empirical work demonstrating the benefits and costs of using public information to estimate food patch quality; (iii) we examine recent work showing that individuals may also be using public information to improve their estimates of the quality of such disparate environmental parameters as breeding patches, opponents and mates; and finally (iv) we suggest avenues of future work to better understand the nature of public information use and when it might be used or ignored. Such work should lead to a more complete understanding of the behaviour of individuals in social aggregations.
|
|
|
|
Pérez-Barbería, F. J., Shultz, S., Dunbar, R. I. M., & Janis, C. (2007). Evidence For Coevolution Of Sociality And Relative Brain Size In Three Orders Of Mammals. Evolution, 61(12), 2811–2821.
Abstract: Abstract
As the brain is responsible for managing an individual's behavioral response to its environment, we should expect that large relative brain size is an evolutionary response to cognitively challenging behaviors. The “social brain hypothesis” argues that maintaining group cohesion is cognitively demanding as individuals living in groups need to be able to resolve conflicts that impact on their ability to meet resource requirements. If sociality does impose cognitive demands, we expect changes in relative brain size and sociality to be coupled over evolutionary time. In this study, we analyze data on sociality and relative brain size for 206 species of ungulates, carnivores, and primates and provide, for the first time, evidence that changes in sociality and relative brain size are closely correlated over evolutionary time for all three mammalian orders. This suggests a process of coevolution and provides support for the social brain theory. However, differences between taxonomic orders in the stability of the transition between small-brained/nonsocial and large-brained/social imply that, although sociality is cognitively demanding, sociality and relative brain size can become decoupled in some cases. Carnivores seem to have been especially prone to this.
|
|
|
|
Krueger, K., & Heinze, J. (2008). Horse sense: social status of horses (Equus caballus) affects their likelihood of copying other horses` behavior. Anim. Cogn., 11(3), 431–439.
Abstract: Animals that live in stable social groups need to gather information on their own relative position in the group`s social hierarchy, either by directly threatening or challenging others, or in a less costly manner, by observing interactions among others. Such indirect inference of dominance relationships has previously been reported from primates, rats, and birds and fish. Here, we show that domestic horses, Equus caballus, are similarly capable of social cognition. Taking advantage of a specific “following behavior” that horses show towards humans in a riding arena, we investigated whether bystander horses adjust their response to an experimenter according to the observed interaction and their own dominance relationship with the horse whose reaction to the experimenter they had observed before. Horses copied the following behavior towards an experimenter after watching a dominant horse following, but did not follow after observing a subordinate horse or a horse from another social group doing so. The following behavior which horses show towards an experimenter therefore appears to be affected by the demonstrator`s behavior and social status relative to the observer.
|
|
|
|
Krueger, K. (Ed.). (2008). Proceedings of the International Equine Science Meeting 2008. Wald: Xenophon Verlag.
Abstract: Target group: Biologists, Psychologists, Veterinarians and Professionals
Meeting target: Because the last international meeting on Equine Science took place a couple years ago, there is an urgent need for equine scientists to exchange scientific knowledge, coordinate research provide knowledge for practical application, and discus research results among themselves and with professionals who work with horses. Additionally, dialog concerning the coordination of the study “Equitation Science” in Europe is urgently needed. Coordination and cooperation shall arise from the meeting, enrich the research, and advance the application of scientific knowledge for the horses` welfare.
|
|
|
|
Wey, T., Blumstein, D. T., Shen, W., & Jordán, F. (2008). Social network analysis of animal behaviour: a promising tool for the study of sociality. Anim. Behav., 75(2), 333–344.
Abstract: Social animals live and interact together, forming complex relationships and social structure. These relationships can have important fitness consequences, but most studies do not explicitly measure those relationships. An approach that explicitly measures relationships will further our understanding of social complexity and the consequences of both direct and indirect interactions. Social network analysis is the study of social groups as networks of nodes connected by social ties. This approach examines individuals and groups in the context of relationships between group members. Application of social network analysis to animal behaviour can advance the field by identifying and quantifying specific attributes of social relationships, many of which are not captured by more common measures of sociality, such as group size. Sophisticated methods for network construction and analysis exist in other fields, but until recently, have seen relatively little application to animal systems. We present a brief history of social network analysis, a description of basic concepts and previous applications to animal behaviour. We then highlight relevance and constraints of some network measures, including results from an original study of the effect of sampling on network parameter estimates, and we end with promising directions for research. By doing so, we provide a prospective overview of social network analysis' general utility for the study of animal social behaviour.
|
|
