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Smith, B. R., & Blumstein, D. T. (2008). Fitness consequences of personality: a meta-analysis. Behav. Ecol., 19(2), 448–455.
Abstract: The study of nonhuman personality capitalizes on the fact that individuals of many species behave in predictable, variable, and quantifiable ways. Although a few empirical studies have examined the ultimate consequences of personality differences, there has been no synthesis of results. We conducted a formal meta-analysis of published studies reporting fitness consequences of single personality dimensions to identify general trends across species. We found bolder individuals had increased reproductive success, particularly in males, but incurred a survival cost, thus, supporting the hypothesis that variation in boldness was maintained due to a “trade-off” in fitness consequences across contexts. Potential mechanisms maintaining variation in exploration and aggression are not as clear. Exploration had a positive effect only on survival, whereas aggression had a positive effect on both reproductive success and, not significantly, on survival. Such results would suggest that selection is driving populations to become more explorative and aggressive. However, limitations in meta-analytic techniques preclude us from testing for the effects of fluctuating environmental conditions or other forms of selection on these dimensions. Results do, however, provide evidence for general relationships between personality and fitness, and we provide a framework for future studies to follow in the hopes of spurring more in-depth, long-term research into the evolutionary mechanisms maintaining variation in personality dimensions and overall behavioral syndromes. We conclude with a discussion on how understanding and managing personality traits may play a key role in the captive breeding and recovery programs of endangered species.
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Smith, J. E., Kolowski, J. M., Graham, K. E., Dawes, S. E., & Holekamp, K. E. (2008). Social and ecological determinants of fission-fusion dynamics in the spotted hyaena. Anim. Behav., 76(3), 619–636.
Abstract: Theory predicts that individuals living in fission-fusion societies, in which group members frequently change subgroups, should modify grouping patterns in response to varying social and environmental conditions. Spotted hyaenas, Crocuta crocuta, are long-lived carnivores that reside in permanent social groups called clans. Clans are complex, fission-fusion societies in which individual members travel, rest and forage in subgroups that frequently change composition. We studied two clans in Kenya to provide the first detailed description of fission-fusion dynamics in this species. Because social and ecological circumstances can influence the cohesiveness of animal societies, we evaluated the extent to which specific circumstances promote the formation of subgroups of various sizes. We found that cooperative defence of shared resources during interclan competition and protection from lions were cohesive forces that promoted formation of large subgroups. We also tested hypotheses suggesting factors limiting subgroup size. Mothers with small cubs avoided conspecifics, thereby reducing infanticide risk. Victims of aggression either reconciled fights or separated from former opponents to reduce the immediate costs of escalated aggression in the absence of food. As predicted by the ecological constraints hypothesis, hyaenas adjusted their grouping patterns over both short and long time scales in response to feeding competition. Crocuta were most gregarious during periods of abundant prey, joined clanmates at ephemeral kills in numbers that correlated with the energetic value of the prey and gained the most energy when foraging alone because cooperative hunting attracted numerous competitors. Overall, our findings indicate that resource limitation constrains grouping in this species.
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Sovrano, V., & Bisazza, A. (2008). Recognition of partly occluded objects by fish. Anim. Cogn., 11(1), 1435–9448.
Abstract: Abstract The ability to visually complete partly occluded objects (so-called `“amodal completion”) has been documented in mammals and birds. Here, we report the first evidence of such a perceptual ability in a fish species. Fish (Xenotoca eiseni) were trained to discriminate between a complete and an amputated disk. Thereafter, the fish performed test trials in which hexagonal polygons were either exactly juxtaposed or only placed close to the missing sectors of the disk in order to produce or not produce the impression (to a human observer) of an occlusion of the missing sectors of the disk by the polygon. In another experiment, fish were first trained to discriminate between hexagonal polygons that were either exactly juxtaposed or only placed close to the missing sectors of a disk, and then tested for choice between a complete and an amputated disk. In both experiments, fish behaved as if they were experiencing visual completion of the partly occluded stimuli. These findings suggest that the ability to visually complete partly occluded objects may be widespread among vertebrates, possibly inherited in mammals, birds and fish from early vertebrate ancestors.
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Streit, S., Zeitler-Feicht, M. H., & Dempfle, L. (2008). Gibt es in der Gruppenhaltung von Pferden bei der Abruffütterung am Automaten mehr Auseinandersetzungen als bei der Fütterung in Fressständen? [Keeping horses in groups, are there more confrontations when feeding is done with automatic feeding systems than with feeding stalls?]. In KTBL-Schriften (Vol. 471). KTBL.
Abstract: Das Droh- und Meideverhalten von 270 Pferden wurde im Fressbereich von 10 Offenlaufställen
mit Fressständen und 11 Offenlaufställen mit computergesteuerten Abrufstationen anhand von visuellen kontinuierlichen Direktbeobachtungen erfasst. Diese erfolgten je Betrieb über einen 24-Stunden-Tag, der nach dem Tortenstückverfahren (6x4 Stunden) zusammengesetzt war. Insgesamt wurden 6297 agonistische Verhaltensweisen in, vor und hinter den Fütterungseinrichtungen registriert (Meiden 40,6 %, Verdrängen 12,8 %, Beißen/ Hinterhandschlag/ Angehen 12,7 % und Drohen/ Drohbeißen/ Hinterhanddrohen 33,9 %). In den Futterstationen wurden 22,5 % dieses Verhaltens beobachtet, vor und hinter den Futterstationen 77,5 %. Bei den Betrieben mit Fressständen fanden 31 % der agonistischen Verhaltensweisen in den Ständen statt, bei den Betrieben mit Abruffütterung 21 %. Der Einfl uss des einzelnen Betriebes (innerhalb Fütterungssystem) auf die agonistischen Verhaltensweisen vor und hinter den Fütterungseinrichtungen war signifi kant. Die Auswertung ergab, dass Drohgesten im Wartebereich von Abrufstationen häufi ger auftreten als in dem von Fressständen. Demgegenüber können Pferde in Abrufstationen ungestörter fressen. Insgesamt betrachtet war jedoch die Anzahl an sozionegativen Interaktionen im Bereich der Futtereinrichtungen bei beiden Fütterungssystemen gering. Die agonistischen Verhaltensweisen wurden zusätzlich noch von der Heumenge und dem Konstitutionstyp beeinfl usst. Der Betrieb erwies sich als maßgeblicher Einfl ussfaktor. Als Resümee ergibt sich, dass bei ordnungsgemäßer Gruppenhaltung mit fachgerechtem Management beide Fütterungssysteme für Pferde im Offenlaufstall geeignet sind. [The threatening and avoiding behaviour of 270 horses living in run-out sheds was observed at 10 stables with feeding stalls and at 11 stables with automatic feeding systems for hay and concentrates. Every group of horses was observed on five succeeding days visually and immediately for 6 sessions, each of 4 hours. These 6 slices form together 24 hours, a complete day. Altogether, 6297 agonistic behaviour patterns were registered in front of, inside and behind the feeding stations (avoiding behaviour 40.6 %, edging out of others 12.8 %, Auseinandersetzungen an automatischer Abruffütterung und Fressständen KTBL-Schrift 471 79 biting/rear leg kicking/charging 12.7 % und threatening/biting threats/rear leg kicking threats 33.9 %). 22.5 % of these types of behaviour were recorded in the feeding stations, 77.5 % together in front and behind of these. In the stables with feeding stalls there were 31 % of the observed threatening gestures inside the feeding stations, in the stables with automatic feeders only 21 %. The individual farm showed signifi cant infl uence on the modes of agonistic behaviour in front and behind the feeding facilities. Threatening gestures happen more often in the waiting area of automatic feeders than in that of feeding stalls. On the other hand horses in computer controlled systems will be less disturbed at eating. All together the number of negative interactions in the feeding area at both feeding systems was relatively low. In addition the agonistic behaviour was infl uenced by the quantity of hay and the constitutional typ of the horses. Because of the management of the individual stable exercises the most substantial infl uence on the behaviour of the horses, it can be said, that, correct group keeping with professional management provided, both feeding systems are suitable for horses in run-in sheds.] |
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Streit,, S., Zeitler-Feicht, M. H., & Dempfle, L. (2008). Automatic feeding systems versus feeding stalls for horses kept in groups: visiting frequency, stress situations and risk of injury. In IESM 2008.
Abstract: When keeping horses in run-out sheds, feeding stalls are usually recommended for individual feeding; which allows equine typical simultaneous eating. However, automatic feeding devices for hay and concentrates are being increasingly used, and these do not allow simultaneous eating. This research aims to compare visiting frequency, stress situations, and the risk of injury, in the area of automatic feeding systems with those at feeding stalls. The studies were carried out at 10 stables with feeding stalls and at 11 with automatic feeding systems for hay and concentrates. These stables were otherwise similar regarding the keeping of the horses and the management of the facilities. Each group consisted of 8 to 21 horses, with 260 horses taking part in total. Every group was observed for 6 sessions, each of 4 hours. These 6 sessions together made 24 hours, a complete day.
Horses in stables with feeding stalls visited the feeding area (waiting area, the station, exit area) 45.5 ± 27.3 times on average in 24 hours, and in stables with automatic feeders for hay and concentrates, 93.1 ± 53.5 times. This difference was significant. Threatening behaviour, without risk of injury or with risk of injury, occurred significantly more frequently in stables with automatic feeders (9.6 ± 12.9 times and 4.2 ± 5.5 times respectively per 24 hours and horse) than in stables with feeding stalls (6.0 ± 10.4 times and 1.5 ± 3.3 times respectively per 24 hours and horse). The management of the stable, however, proved to have its most important influence on the behaviour of the horses. Displacement activities were observed in stables with feeding stalls 0.3 ± 1.0 times per horse and 24 hours and in stables with automatic feeders for hay and concentrate 12.9 ± 23.3 times. Situations that could cause either stress or injuries to the horses occurred in stables with feeding stalls within 24 hours per horse only 3.7 ± 13.1 and 1.3 ± 4.8 times on average respectively. Such situations were to be seen in stables with automatic feeder 17.0 ± 33.4 and 8.6 ± 15.3 times respectively per horse and 24 hours – clearly more often. We may therefore conclude that the more often the feeding area is visited, the more frequently threatening gestures without and with risk of injury occur. The same goes for the number of situations that may result in stress or injuries. Therefore to sum up it can be said that feeding in feedings stalls leads to less risk of stress and injuries compared with feeding by computer controlled systems. On the other hand, computer controlled systems have the advantage of stimulating the horses to move, which is very important for their health. While assessing this study it should be taken into account that there were very big individual differences between the horses. The result of the statistical evaluation was that the management of the stable has a decisive influence on the observed features. Therefore both feeding systems can be recommended, especially as the number of conflicts in the feeding area in all stables was relatively low and no injuries were observed in connection with the feeding. |
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Stueckle, S., & Zinner, D. (2008). To follow or not to follow: decision making and leadership during the morning departure in chacma baboons. Anim. Behav., 75(6), 1995–2004.
Abstract: To benefit from group living, group members need to keep the group cohesive by coordinating time and direction of travelling. Self-organization and leadership are two means of coordination and two types of decision can be made on the group level: combined and consensus. We studied the initiation process of group movements during the morning departure of a group of chacma baboons, Papio hamadryas ursinus, from its sleeping site in De Hoop Nature Reserve, South Africa. Findings from other female-bonded primate groups led us to hypothesize that females should play a major role in the decision-making process. Approximately 75% of the adults made a start attempt, with 62 of 92 attempts being by males. There was no sex difference in the probability of being successful when initiating an attempt. Lactating females initiated fewer than pregnant or cycling females. Thus, at least for this group of chacma baboons, leadership appeared to be distributed and the decision about the timing of departure and travel direction seemed to be a partially shared consensus decision with adult males contributing more to the decision outcome, with a slightly more prominent role of the dominant male. Our results do not support the [`]leading females' hypothesis. No behavioural patterns that might serve as specialized signals leading to a more successful recruitment of other group members were observed. The departure process appeared to be coordinated merely through individuals setting an example by moving off.
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Stupperich, A., & Strack, M. (2008). Interaction with horses (equus): Assessment with a circumplex based questionnaire. In IESM 2008.
Abstract: According to Interpersonal Theory every interaction is motivated by efforts to achieve and maintain self-esteem and to avoid anxiety. People"s characteristic ways of accomplishing these ends are called interpersonal reflexes. Those interpersonal reflexes are evident in interaction with animals, since they are determined by the interpersonal traits of personality. We wanted to catch the typical interpersonal reflexes in between humans and horses compared to pet animals.
We used the self rating assessment instrument “Inventory of Problematic Interactions with Animals” (IPI – Animals), which bases on a Interpersonal Circumplex Model (Human Animal Circumplex; HAC) and was constructed to catch specific dispositions of distress caused by animals using two dimensions (too dominant vrs too submissive and too warm versus too cold). Data of 233 male adolescents (93 of them actual pet owners, from that 12 horse owners) were collected. We found that different pet preferences holds distinct locations in the HAC. Horse persons differ from dog and cat persons within the dimension dominance (dog: chi2(df126) =161.54 p= .018; cat: chi2(df126) =199.95 p= .045). Persons, who own a horse or would wish to own one, describe themselves as dominant, but warm interactors. They report that they want horses to notice them. They tend do too much for them and behave very effusively with them. On the other hand they feel that the animal takes too much advantage of the relationship. |
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Subiaul, F., Vonk, J., Okamoto-Barth, S., & Barth, J. (2008). Do chimpanzees learn reputation by observation? Evidence from direct and indirect experience with generous and selfish strangers. Anim. Cogn., 11(4), 611–623.
Abstract: Abstract  Can chimpanzees learn the reputation of strangers indirectly by observation? Or are such stable behavioral attributions made exclusively by first-person interactions? To address this question, we let seven chimpanzees observe unfamiliar humans either consistently give (generous donor) or refuse to give (selfish donor) food to a familiar human recipient (Experiments 1 and 2) and a conspecific (Experiment 3). While chimpanzees did not initially prefer to beg for food from the generous donor (Experiment 1), after continued opportunities to observe the same behavioral exchanges, four chimpanzees developed a preference for gesturing to the generous donor (Experiment 2), and transferred this preference to novel unfamiliar donor pairs, significantly preferring to beg from the novel generous donors on the first opportunity to do so. In Experiment 3, four chimpanzees observed novel selfish and generous acts directed toward other chimpanzees by human experimenters. During the first half of testing, three chimpanzees exhibited a preference for the novel generous donor on the first trial. These results demonstrate that chimpanzees can infer the reputation of strangers by eavesdropping on third-party interactions.
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Sueur, C., & Petit, O. (2008). Shared or unshared consensus decision in macaques? Behav. Process., 78(1), 84–92.
Abstract: Members of a social group have to make collective decisions in order to synchronise their activities. In a shared consensus decision, all group members can take part in the decision whereas in an unshared consensus decision, one individual, usually a dominant member of the group, takes the decision for the rest of the group. It has been suggested that the type of decision-making of a species could be influenced by its social style. To investigate this further, we studied collective movements in two species with opposed social systems, the Tonkean macaque (Macaca tonkeana) and the rhesus macaque (Macaca mulatta). From our results, it appears that the decision to move is the result of the choices and actions of several individuals in both groups. However, this consensus decision involved nearly all group members in Tonkean macaques whereas dominant and old individuals took a prominent role in rhesus macaques. Thus, we suggest that Tonkean macaques display equally shared consensus decisions to move, whereas in the same context rhesus macaque exhibit partially shared consensus decisions. Such a difference in making a collective decision might be linked to the different social systems of the two studied species.
Keywords: Collective movement; Decision-making; Leadership; Social style
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Sueur, C., & Petit, O. (2008). Organization of Group Members at Departure Is Driven by Social Structure in Macaca. Int. J. Primatol., 29(4), 1085–1098.
Abstract: Abstract Researchers have often explained order of progression of group members during joint movement in terms of the influence of ecological pressures but rarely that of social constraints. We studied the order of joining by group members to a movement in semifree-ranging macaques with contrasting social systems: 1 group of Tonkean macaques (Macaca tonkeana) and 1 group of rhesus macaques (M. mulatta). We used network metrics to understand roles and associations among individuals. The way the macaques joined a movement reflected the social differences between the species in terms of dominance and kinship. Old and dominant male rhesus macaques were more often at the front of the movement, contrary to the Tonkean macaques, which exhibited no specific order. Moreover, rhesus macaques preferred to join high-ranking or related individuals, whereas Tonkean macaques based associations during joining mostly on sexual relationships with a subgroup of peripheral males.
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