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Adams, E. S. (2005). Bayesian analysis of linear dominance hierarchies. Anim. Behav., 69(5), 1191–1201.
Abstract: Studies on social animals often seek to identify dominance hierarchies, in which individuals are ranked according to competitive abilities based on counts of wins and losses in pairwise encounters. I illustrate Bayesian approaches, based on the method of paired comparisons, for determining ranks and for estimating relationships between dominance ability and other attributes. Bayesian inference combines prior probability distributions for each unknown parameter with likelihood functions to produce the joint posterior probability distribution for the quantities of interest. In contrast to nonparametric techniques for inferring ranks, Bayesian models yield measures of certainty for each inference and allow rigorous estimates of correlations between ranks and covariates even when there is considerable uncertainty as to the ranks themselves. A possible objection to the Bayesian approach is that it appears to entail more restrictive assumptions than do simpler methods. However, simulations show that Bayesian inferences are more robust to deviations from these assumptions than are the results of nonparametric methods.
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Hanggi, E. B. (2005). The Thinking Horse: Cognition and Perception. In International Veterinary Information Service (Vol. 51).
Abstract: Cognition and perception in horses has often been misunderstood. Not only in the past but even today, people proclaim that horses react only by instinct, that they are just conditioned-response animals, that they lack advanced cognitive ability, and that they have poor visual capabilities (e.g., acuity, color vision, depth perception). Until relatively recently, there was little scientific evidence to address such beliefs. Change, however, is underway as scientific and public interest in all aspects of equine learning and perception intensifies. A review of the scientific literature, as well as practical experience, shows that horses excel at simpler forms of learning such as classical and operant conditioning, which is not surprising considering their trainability when these principles and practices are applied. Furthermore, horses have shown ease in stimulus generalization and discrimination learning. Most recently and unexpected by many, horses have solved advanced cognitive challenges involving categorization learning and some degree of concept formation. A comprehensive understanding of the cognitive and perceptual abilities of horses is necessary to ensure that this species receives proper training, handling, management, and care.
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Feh, C. (2005). Relationships and Communication in Socially Natural Horse Herds. In D. S. Mills, & S. M. McDonnell (Eds.), The domestic horse : the origins, development, and management of its behaviour. Cambridge: Cambridge University Press 2005.
Abstract: Horses are quite unique. In most mammals, sexes segregate and maintain bonds only during the breeding season (Clutton-Brock, 1989). Some canids, a few rodents and primate species such as gorillas, hamadryas baboons and red howler monkeys are the exception, where the same males stay with the same females all year round and over many breeding seasons. Typically, both sexes disperse at puberty in these species. In horses, it was clearly shown that the causes for female dispersal were incest avoidance and not intra-specific competition (Monard, 1996). As a rule, this is confirmed for mammal species where tenure length by males exceeds the age at first reproduction in females (Clutton-Brock, 1989). When horses are allowed to choose their mating partner freely, the inbreeding coefficient of the offspring is lower than expected should they mate randomly (Duncan et al, 1984).
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Hare, J. F. (2005). Lee Alan Dugatkin, Principles of Animal Behavior, Norton, New York (2004) Pp. xx+596. Price $80.00. Anim. Behav., 69(1), 247–248.
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Godin, J. - G. J., Herdman, E. J. E., & Dugatkin, L. A. (2005). Social influences on female mate choice in the guppy, Poecilia reticulata: generalized and repeatable trait-copying behaviour. Anim. Behav., 69(4), 999–1005.
Abstract: In vertebrates, the mating preferences of individual females can be flexible and the probability of a female mating with a particular male can be significantly increased by her having previously observed another conspecific female affiliate and mate with that same male. In theory, such mate-choice-copying behaviour has potentially important consequences for both the genetic and social (`cultural') transmission of female mating preferences. For copying to result in the `cultural inheritance' of mating preferences, individual females must not only copy the mate choice decisions of other females but they also should tend to repeat this type of behaviour (i.e. make similar mating decisions) subsequently and to generalize their socially induced preference for a particular male to other males that share his distinctive characteristics. Here, we show experimentally that individual female guppies, Poecilia reticulata, not only copy the observed mating preferences of other females for particular males, but that the preference now assumed via copying is subsequently repeated and generalized to other males of a similar colour phenotype. These results provide empirical evidence for social enhancement of female preference for particular phenotypic traits of chosen males rather than for the particular males possessing those traits, and thus have important implications for our understanding of the role of social learning in the evolution of female mating preferences and of male epigamic traits.
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Murphy, J., Sutherland, A., & Arkins, S. (2005). Idiosyncratic motor laterality in the horse. Appl. Anim. Behav. Sci., 91(3-4), 297–310.
Abstract: Idiosyncratic motor behaviour was investigated during four experimental procedures in 40 horses (males = 20, females = 20) to establish if horses revealed evidence of significant right or left laterality. The experimental procedures included (1) detection of the preferred foreleg to initiate movement (walk or trot), (2) obstacle avoidance within a passageway (right or left), (3) obstacle avoidance when ridden and (4) idiosyncratic motor bias when rolling. The influence of the horses' sex on both the direction and the degree of the laterality was explored within and between experimental procedures. The findings showed that the direction, but not the degree of idiosyncratic motor preference in the horses was strongly sex-related. Male horses exhibited significantly more (t = 3.74, d.f. = 79, P < 0.001) left lateralised responses and female horses exhibited significantly more (t = -6.35, d.f. = 79, P < 0.01) right lateralised responses. There was also significant positive correlation (P < 0.05) between four of six possible inter-experimental relationships. The results suggest two discrete trends of laterality associated with the sex of the horse. The primary cause of idiosyncratic motor laterality may be genetically predetermined, influenced by environmental factors or a combination of these two and the current findings may support the development of sex-specific training schedules for the horse. Further, work in this area might assist in defining the mechanisms of brain hemisphere lateralisation and allocation of cognitive function in the horse.
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Kaminski, J., Riedel, J., Call, J., & Tomasello, M. (2005). Domestic goats, Capra hircus, follow gaze direction and use social cues in an object choice task. Anim. Behav., 69(1), 11–18.
Abstract: Gaze following is a basic social cognitive skill with many potential benefits for animals that live in social groups. At least five primate species are known to follow the gaze of conspecifics, but there have been no studies on gaze following in other mammals. We investigated whether domestic goats can use the gaze direction of a conspecific as a cue to find food. They were able to do this, at a level comparable to that of primates. In a second experiment, we tested goats' ability to use gaze and other communicative cues given by a human in a so-called object choice situation. An experimenter hid food out of sight of the subject under one of two cups. After baiting the cup the experimenter indicated the location of the food to the subject by using different cues. The goats used communicative cues (touching and pointing) but not gaze by itself. Since domestic dogs are very skilled in this task, whereas wolves are not, one hypothesis is that the use of communicative cues in the object choice task is a side-effect of domestication.
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Nathan J. Emery. (2005). The Evolution of Social Cognition. In The Cognitive Neuroscience of Social BehaviourGarten. Psychology Press.
Abstract: Although this bookis focusedon the cognitive neuroscience ofhuman social behaviour, an
understandingofsocial cognition in non-human animals is critical for unravellingthe neural basis of
social cognition in humans as well as the selective pressures that have shapedthe evolution ofcomplex
social cognition. Thanks to methodological limitations, we know little about the relationships between
certain biochemical andelectrophysiological properties ofthe human brain andhow theycompute the
behaviour andmental states ofother individuals. Traditional techniques for examiningneural function
in humans, such as event-relatedpotentials (ERP),positron emission tomography(PET),and
functional magnetic resonance imaging(fMRI),are constrainedbythe fact that subjects are placed
either into an immoveable scanner with a lot ofbackgroundnoise or wiredup with dozens of
electrodes that are sensitive to slight movements. The possibilityofscanningor recordingbrain waves
from two individuals that are physicallyinteractingsociallyis technicallyimpossible at present
(however, see Montague et al, 2002 for a new methodfor simultaneouslyscanningtwo individuals
interactingvia a computer).
The onlywayto understandthe neurocognitive architecture ofhuman social behaviour is to examine
similar social processes in both human andnon-human animal minds andmake comparisons at the
species level. An additional argument is that traditional human socio-cognitive tasks are dependent on
the use ofstories, cartoons andverbal cues andinstructions (Heberlein & Adolphs, this volume)which
themselves will elicit specific neural responses that have to be eliminatedfrom neural responses
specificallyrelatedto mindreading. Therefore, the development ofnon-verbal tasks wouldprovide a
breakthrough for studies in non-linguistic animals, pre-verbal human infants andhuman cognitive
neuroimaging.
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Hare, B., & Tomasello, M. (2005). Human-like social skills in dogs? Trends. Cognit. Sci., 9(9), 439–444.
Abstract: Domestic dogs are unusually skilled at reading human social and communicative behavior--even more so than our nearest primate relatives. For example, they use human social and communicative behavior (e.g. a pointing gesture) to find hidden food, and they know what the human can and cannot see in various situations. Recent comparisons between canid species suggest that these unusual social skills have a heritable component and initially evolved during domestication as a result of selection on systems mediating fear and aggression towards humans. Differences in chimpanzee and human temperament suggest that a similar process may have been an important catalyst leading to the evolution of unusual social skills in our own species. The study of convergent evolution provides an exciting opportunity to gain further insights into the evolutionary processes leading to human-like forms of cooperation and communication.
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Digweed, S. M., Fedigan, L. M., & Rendall, D. (2005). Variable specificity in the anti-predator vocalizations and behaviour of the white-faced capuchin, Cebus capucinus. Behaviour, 142(8). Retrieved June 18, 2024, from http://dx.doi.org/10.1163/156853905774405344
Abstract: (Accepted: 23 June 2005)
Summary
Much research in animal communication is aimed at understanding the functional design
features of animal vocal signals. Our detailed analyses of the vocalizations and behavioural
responses elicited in white-faced capuchins by predators and other disturbances point to two
call variants that differ modestly in their acoustic structure and that are accompanied by
functionally distinct behavioural responses. The first variant is given exclusively to avian
predators and is almost invariably accompanied by the monkeys immediate descent from
the treetops where it is most vulnerable; therefore, we label this call variant the aerial
predator alarm?. The second variant, that differs only slightly but noticeably from the first,
is given to a wide range of snakes and mammals, including a range of species that represent
no predatory threat to the monkeys. This second call is also associated with more variable
responses from calling monkeys, from delayed retreat from the source of disturbance, to
active approach, inspection, and sometimes mobbing of the animal involved. We therefore
label this variant more generally as an “alerting call”. Although some other primate species
show a more diverse system of anti-predator calls, and the capuchins themselves may yet
be found to produce a greater variety of calls, a system of two call variants with varying
degrees of predator specificity and behavioural response is not uncommon among primates
and appears functionally appropriate for capuchins. The basic structure of the alerting call
allows conspecific listeners to localize the caller and the source of disturbance readily, thereby
allowing listeners to approach and assist in mobbing in cases where the disturbance warrants
it, or to avoid the area in cases where the disturbance is identified as a predatory threat.
Conversely, the aerial predator alarm is inherently less localizable and therefore conveys the
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