| Home | << 1 2 3 4 5 6 7 8 9 10 >> [11–20] |
|
Christensen, J. W., Ahrendt, L. P., Lintrup, R., Gaillard, C., Palme, R., & Malmkvist, J. (2012). Does learning performance in horses relate to fearfulness, baseline stress hormone, and social rank? In Applied Animal Behaviour Science (Vol. 140, pp. 44–52).
Abstract: The ability of horses to learn and remember new tasks is fundamentally important for their use by humans. Fearfulness may, however, interfere with learning, because stimuli in the environment can overshadow signals from the rider or handler. In addition, prolonged high levels of stress hormones can affect neurons within the hippocampus; a brain region central to learning and memory. In a series of experiments, we aimed to investigate the link between performance in two learning tests, the baseline level of stress hormones, measured as faecal cortisol metabolites (FCM), fearfulness, and social rank. Twenty-five geldings (2 or 3 years old) pastured in one group were included in the study. The learning tests were performed by professional trainers and included a number of predefined stages during which the horses were gradually trained to perform exercises, using either negative (NR) or positive reinforcement (PR). Each of the learning tests lasted 3 days; 7min/horse/day. The NR test was repeated in a novel environment. Performance, measured as final stage in the training programme, and heart rate (HR) were recorded. Faeces were collected on four separate days where the horses had been undisturbed at pasture for 48h. Social rank was determined through observations of social interactions during feeding. The fear test was a novel object test during which behaviour and HR were recorded. Performance in the NR and PR learning tests did not correlate. In the NR test, there was a significant, negative correlation between performance and HR in the novel environment (rS=-0.66, P<0.001, i.e. nervous horses had reduced performance), whereas there was no such correlation in the home environment (both NR and PR). Behavioural reactions in the fear test correlated significantly with performance in the NR test in the novel environment (e.g. object alertness and final stage: rS=-0.43, P=0.04), suggesting that performance under unfamiliar, stressful conditions may be predicted by behavioural responses in a fear test. There was a negative correlation between social rank and baseline stress hormones (rS=-0.43, P=0.04), i.e. high rank corresponded to low FCM concentrations, whereas neither rank nor FCM correlated with fearfulness or learning performance. We conclude that performance under stressful conditions is affected by activation of the sympathetic nervous system during training and related to behavioural responses in a standardised fear test. Learning performance in the home environment, however, appears unrelated to fearfulness, social rank and baseline FCM levels.
Keywords: Horse; Learning; Fearfulness; Stress; Reinforcement; Social rank
|
|
Ahrendt, L. P., Christensen, J. W., & Ladewig, J. (2012). The ability of horses to learn an instrumental task through social observation. In Applied Animal Behaviour Science (Vol. 139, pp. 105–113).
Abstract: The ability of horses to learn through social observation may ease the implementation of new management systems, because the use of automatic feeders etc. by naive horses could be facilitated by observation of experienced horses. However, previous studies found no documentation for observational learning abilities in horses. This study aimed to investigate the ability of horses to learn an instrumental task from a familiar conspecific when social interaction was allowed during the demonstration. Two similar experiments were performed. In the first experiment, Observer horses (n=11) participated in ten successive demonstrations, where a trained Demonstrator opened an operant device by pushing a sliding lid aside with the muzzle in order to obtain a food reward. Immediately after the demonstrations the Observer horses were given the opportunity to operate the device alone. Control horses (n=11) were aware that the device contained food but were presented to the operant device without demonstration of the task. The learning criterion was at least two openings. Accomplishment of and latency to accomplish the learning criterion, and investigative behaviour towards the operant device were recorded. Five Observers and one Control, out of the eleven horses in each treatment group, accomplished the learning criterion. Even though this presents a high odds ratio (OR) in favour of the Observer treatment (OR=7.6), there was no significant difference between the treatment groups (P=0.15). Analysis of investigative behaviour showed, however, that the demonstrations increased the motivation of the Observer horses to investigate the device. Subsequently, a similar experiment was performed in a practical setting with 44 test horses (mixed age, gender and breed). We used the same operant device and the same number and type of demonstrations, although the horses were held on a loose rope to minimise aggression. In this second experiment, six of 23 Observer horses and five of 21 Control horses learned the instrumental task, representing no influence of the demonstration. Thus, this study did not demonstrate an ability of horses to learn an instrumental task through observation.
|
|
Bergmüller, R. (2010). Animal Personality and Behavioural Syndromes. In P. Kappeler (Ed.), Animal Behaviour – Evolution and Mechanisms (pp. 587–621). Heidelberg: Springer.
|
|
van Schaik, C. P. (2010). Social learning and culture in animals. In P. Kappeler (Ed.), Animal Behaviour: Evolution and Mechanisms (pp. 623–653). Springer Berlin Heidelberg.
Abstract: Most animals must learn some of the behaviours in their repertoire, and some must learn most. Although learning is often thought of as an individual exercise, in nature much learning is social, i.e. under the influence of conspecifics. Social learners acquire novel information or skills faster and at lower cost, but risk learning false information or useless skills. Social learning can be divided into learning from social information and learning through social interaction. Different species have different mechanisms of learning from social information, ranging from selective attention to the environment due to the presence of others to copying of complete motor sequences. In vertical (or oblique) social learning, naïve individuals often learn skills or knowledge from parents (or other adults), whereas horizontal social learning is from peers, either immatures or adults, and more often concerns eavesdropping and public information use. Because vertical social learning is often adaptive, maturing individuals often have a preference for it over individual exploration. The more cognitively demanding social learning abilities probably evolved in this context, in lineages where offspring show long association with parents and niches are complex. Because horizontal learning can be maladaptive, especially when perishable information has become outdated, animals must decide when to deploy social learning. Social learning of novel skills can lead to distinct traditions or cultures when the innovations are sufficiently rare and effectively transmitted socially. Animal cultures may be common but to date taxonomic coverage is insufficient to know how common. Cultural evolution is potentially powerful, but largely confined to humans, for reasons currently unknown. A general theory of culture is therefore badly needed.
Keywords: Life Sciences
|
|
Kerth, G. (2010). Group decision-making in animal societies. In P. Kappeler (Ed.), Animal Behaviour: Evolution and Mechanisms (pp. 241–265). Springer Berlin Heidelberg.
Abstract: Individuals need to coordinate their activities to benefit from group living. Thus group decisions are essential for societies, especially if group members cooperate with each other. Models show that shared (democratic) decisions outperform unshared (despotic) decisions, even if individuals disagree about actions. This is surprising as in most other contexts, differences in individual preferences lead to sex-, age-, or kin-specific behaviour. Empirical studies testing the predictions of the theoretical models have only recently begun to emerge. This applies particularly to group decisions in fission-fusion societies, where individuals can avoid decisions that are not in their interest. After outlining the basic ideas and theoretical models on group decision-making I focus on the available empirical studies. Originally most of the relevant studies have been on social insects and fish but recently an increasing number of studies on mammals and birds have been published, including some that deal with wild long-lived animals living in complex societies. This includes societies where group members have different interests, as in most mammals, and which have been less studied compared to eusocial insects that normally have no conflict among their colony members about what to do. I investigate whether the same decision rules apply in societies with conflict and without conflict, and outline open questions that remain to be studied. The chapter concludes with a synthesis on what is known about group decision-making in animals and an outlook on what I think should be done to answer the open questions.
Keywords: Life Sciences
|
|
Gorecka, A., Golonka, M., Chruszczewski, M., & Jezierski, T. (2007). A note on behaviour and heart rate in horses differing in facial hair whorl. Appl. Anim. Behav. Sci., 105(1-3), 244–248.
Abstract: The relationship between facial hair whorl position and reactivity, as assessed by behavioural measures (handling score = HS; startle reaction to a suddenly appearing novel object = SR; latency to touch a novel object = LNO) and heart rate measures (mean HR; increase in heart rate = IHR) were studied using 55 Konik horses reared either under conventional stable conditions or in the forest reserve. Horses were classified into four groups according to the whorl position and/or shape: (1) high, single whorl above the top eye line, n = 9; (2) medium, single whorl between the top and the bottom eye line, n = 30; (3) low, single whorl below the bottom eye line, n = 10; and (4) elongated or double whorl, n = 6. Horses with a high whorl position demonstrated a lesser degree of manageability as expressed by a lower HS compared to individuals with medium (P = 0.002) or low whorl positions (P = 0.016). Horses with different whorl positions did not differ significantly in their startle response to a suddenly appearing novel object (P = 0.685). The horses with an elongated or double whorl, which appeared only in the forest group, took significantly longer to approach the novel object than horses with medium (P = 0.006) or low (P = 0.005) whorl positions. No significant differences in mean HR and IHR between groups (HR: P = 0.629 and IHR: P = 0.214) were found. In conclusion, this study supports the relationship between the position of the hair whorl on the horses' head and their manageability during handling, as well as the latency to approach an unknown object.
Keywords: Horse; Hair whorls; Behavioural tests; Reactivity; Heart rate
|
|
NICOLA J. ROONEY & JOHN W. S. BRADSHAW. (2005). Social cognition in the domestic dog: behaviour of spectators towards participants in interspecific games. Anim. Behav., 72(2), 343–352.
Abstract: previous termSocial cognition,next term in particular the derivation of previous termsocialnext term information from observation of interactions between members of a previous termsocialnext term group, has been widely investigated in primates, but it has received little attention in other previous termsocialnext term mammals, although it has been anecdotally reported in the previous termdomestic dog,next term Canis familiaris. We recorded the behaviour of previous termdogsnext term (“spectators”) that had observed controlled interactions between a human and a previous termdognext term (the “demonstrator”) competing for an object, and that were subsequently allowed to interact freely with both participants. When the competitions were playful, as indicated by signals performed by the human, the spectator was more likely to approach the winner first and/or more rapidly, suggesting that winners of games are perceived as desirable previous termsocialnext term partners. When the human did not perform play signals, changing the previous termsocialnext term context from play to contest over a resource, spectators were slower to approach either of the participants, suggesting that participants in contests were less desirable as previous termsocialnext term partners than participants in games. If the previous termdognext term was prevented from seeing the game, it still reacted differently to the winner and the loser, but its behaviour was not the same as after games that it had seen. We conclude that spectator previous termdogsnext term gain information from the players' subsequent behaviour as well as from direct observation of the game.
|
|
Mateo, J. M. (2006). The nature and representation of individual recognition odours in Belding's ground squirrels. Anim. Behav., 71(1), 141–154.
Abstract: In many taxonomic groups, odours provide cues to species identity, reproductive status, genetic relatedness and individual identity. These odour cues are often used to mark territories or other resources and to recognize individuals through direct or indirect olfactory investigation. Belding's ground squirrels, Spermophilus beldingi, frequently scent-mark their environment and they also investigate the scent glands of conspecifics, which suggests that odours play a modulating role in their social relationships. I conducted studies to determine what information is conveyed by various S. beldingi odours and whether this information is used by conspecifics for social recognition. Spermophilus beldingi produce a number of cues that are individually distinct, including odours from oral, dorsal, pedal and anal glands and from ears, but apparently not from urine, although it is unclear whether all of these odours are used for social recognition. This discrimination among odours of individuals does not require prior familiarity with the odour bearers. The volatile components of some odours are sufficient to permit individual discrimination, which may explain how animals appear to [`]recognize' each other from a short distance. Finally, S. beldingi incorporate multiple odours into their memories of conspecifics as perception of one odour of an individual generalizes to a second odour from it, suggesting a mental representation of familiar individuals. The production of multiple unique odours may facilitate accurate discrimination of conspecifics along several social dimensions, and some of these odours also vary with relatedness. Together, these results indicate a rich olfactory milieu mediating the social lives of S. beldingi.
|
|
Mendres, K. A., & de Waal, F. B. M. (2000). Capuchins do cooperate: the advantage of an intuitive task. Anim. Behav., 60(4), 523–529.
Abstract: We used a cooperative pulling task to examine proximate aspects of cooperation in captive brown capuchin monkeys, Cebus apella. Specifically, our goal was to determine whether capuchins can learn the contingency between their partner's participation in a task and its successful completion. We examined whether the monkeys visually monitored their partners and adjusted pulling behaviour according to their partner's presence. Results on five same-sex pairs of adults indicate that (1) elimination of visual contact between partners significantly decreased success, (2) subjects glanced at their partners significantly more in cooperative tests than in control tests in which no partner-assistance was needed, and (3) they pulled at significantly higher rates when their partner was present rather than absent. Therefore, in contrast to a previous report by Chalmeau et al. (1997, Animal Behaviour, 54, 1215-1225), cooperating capuchins do seem able to take the role of their partner into account. However, the type of task used may be an important factor affecting the level of coordination achieved. Copyright 2000 The Association for the Study of Animal Behaviour.
|
|
de Waal, F. B. M. (2000). Attitudinal reciprocity in food sharing among brown capuchin monkeys. Anim. Behav., 60(2), 253–261.
Abstract: Capuchin monkeys (Cebus apella) share food even if separated by a mesh restraint. Pairs of capuchins were moved into a test chamber in which one of them received apple pieces for 20 min, and the other received carrot pieces for the next 20 min. Previous research had shown a correlation between the rate of food transfer in both directions across female-female dyads. The present study confirmed this result. Reciprocity across dyads can be explained, however, by symmetry in affiliative and tolerant tendencies between two individuals, provided these tendencies determine food sharing. The present study was designed to exclude this symmetry-based explanation by testing each pair (N=16) of adult females on six separate occasions. There existed a significant covariation across tests of sharing in both dyadic directions, a result unexplained by relationship symmetry. Moreover, control procedures (i.e. testing of a food possessor without a partner, or testing of two individuals with the same food or two different foods at the same time) indicated that behaviour during food trials is not fully explained by mutual attraction or aversion. The monkeys take the quality of their own and the partner's food into account, and possessors limit transfers of high-quality foods. Instead of a symmetry-based reciprocity explanation, a mediating role of memory is suggested, and a mirroring of social attitude between partners. Copyright 2000 The Association for the Study of Animal Behaviour.
|