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Huebener, E. (2004). Die Bewegungen von Pferderumpf und -rücken aus der Sicht des Reiters. Tierärztl. Umschau, 6, 327–334.
Abstract: Die Bewegungen von Rumpf und Rücken des Pferdes in der Fortbewegung bestimmen Sitz und Schenkelhilfen – Grundlagen pferdgerechten und kultivierten, feinfühligen Reitens. In ihrer Tendenz ließen sich diese Bewegungen jetzt aus den Fußfolgen der Grundgangarten ableiten. Die Erkenntnisse sind per Video verifiziert. Mit ihrer Übersetzung in Diagramme wurde versucht, den gegenwärtigen Wissensstand für nicht-reitende Wissenschaftler und denkende Reiter gleichermaßen verständlich darzustellen. Die Akzeptanz des aufbereiteten Wissens in der Reiterei würde verbessert, wenn man zu gemessenen Werten für die Bewegungen des Pferderückens und des Pferderumpfes käme. Plädoyer eines “Nur-Reiters” für einschlägige, universitäre Forschung.
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Huebener, E. (2004). Movements of Trunk and Back of the Horse from a Rider's View. Tierärztl. Umschau, 6, 327.
Abstract: The trunk and back movements of the horse during locomotion determine seat position and leg aids of the rider, this is the basis for horse-oriented and cultivated, sensitive riding. In their tendency these movements could now be derived from the foot sequences of the basic paces. The realizations are verified by video. By translating these movements into diagrams, the author is making an attempt to present the current state of knowledge for non-riding scholars and academically oriented riders alike. The acceptance of the prepared riding knowledge would be improved if one could produce measured values of the horse's back and trunk movements. An appeal of a rider for relevant, scholarly research.
Keywords: walk – trot – canter – pain – damages
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RHO, J. R., SRYGLEY, R. B., & CHOE, J. C. (2004). Behavioral ecology of the Jeju pony (Equus caballus): Effects of maternal age, maternal dominance hierarchy and foal age on mare aggression. Ecol. Res., 19(1), 55–63.
Abstract: On Jeju Island, Korea, dominance hierarchy and maternal care according to maternal age were studied in a herd of Jeju ponies (Equus caballus), consisting of 73 mares, their foals and one stallion. Dominance ranks were nearly linear and increased significantly with the age of mares. Most aggressive encounters involved mares under 5 years old. Mares under the age of 5 years have apparently not established their rank. The mean frequency of aggressive actions of mares per hour increased significantly as the day of parturition approached. Aggressive actions of mares with foals decreased significantly as their foals aged. The overall frequency of aggression of mares with foals also decreased significantly with the age of the mares. Our results suggest that the cost of maternal care is lower for older, more dominant mares than for subordinate ones.
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Dall, S. R. X., Houston, A. I., & McNamara, J. M. (2004). The behavioural ecology of personality: consistent individual differences from an adaptive perspective. Ecol. Letters, 7, 734–739.
Abstract: Individual humans, and members of diverse other species, show consistent differences in
aggressiveness, shyness, sociability and activity. Such intraspecific differences in behaviour have been widely assumed to be non-adaptive variation surrounding (possibly) adaptive population-average behaviour. Nevertheless, in keeping with recent calls to apply Darwinian reasoning to ever-finer scales of biological variation, we sketch the fundamentals of an adaptive theory of consistent individual differences in behaviour. Our thesis is based on the notion that such .personality differences. can be selected for if fitness payoffs are dependent on both the frequencies with which competing strategies are played and an individual`s behavioural history. To this end, we review existing models that illustrate this and propose a game theoretic approach to analyzing personality differences that is both dynamic and state-dependent. Our motivation is to provide insights into the evolution and maintenance of an apparently common animal trait: personality, which has far reaching ecological and evolutionary implications. |
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Cheney, D. l., & Seyfarth, R. M. (2004). Social complexity and the information acquired during eavesdropping by primates and other animals. In P. K. McGregor (Ed.), Animal Communication networks. Cambridge, Massachusetts: Cambridge University Press.
Abstract: In many of the studies reviewed in this book, eavesdropping takes the
following form: a subject has the opportunity to monitor, or eavesdrop upon, an interaction between two other animals,Aand B. The subject then uses the information obtained through these observations to assess A`s and B`s relative dominance or attractiveness as a mate (e.g. Mennill et al., 2002; Ch. 2). For example, Oliveira et al. (1998) found that male fighting fish Betta splendens that had witnessed two other males involved in an aggressive interaction subsequently responded more strongly to the loser of that interaction than the winner. Subjects-behaviour could not have been influenced by any inherent differences between the two males, because subjects responded equally strongly to the winner and the loser of competitive interactions they had not observed. Similarly, Peake et al. (2001) presented male great tits Parus major with the opportunity to monitor an apparent competitive interaction between two strangers by simulating a singing contest using two loudspeakers. The relative timing of the singing bouts (as measured by the degree of overlap between the two songs) provided information about each “contestants” relative status. Following the singing interaction, one of the “contestants” was introduced into the male`s territory. Males responded significantly less strongly to singers that had apparently just “lost” the interaction (see also McGregor & Dabelsteen, 1996; Naguib et al., 1999; Ch. 2). What information does an individual acquire when it eavesdrops on others? In theory, an eavesdropper could acquire information of many different sorts: about A, about B, about the relationship between A and B, or about the place of Animal Communication Networks, ed. Peter K. McGregor. Published by Cambridge University Press. c. Cambridge University Press 2005. 583 P1: JZZ/... P2: JZZ/... 0521823617c25.xml CU1917B/McGregor 0 521 582361 7 October 7, 2004 22:31 584 D. L. Cheney & R. M. Seyfarth A`s and B`s relationship in a larger social framework. The exact information acquired will probably reflect the particular species social structure. For example, songbirds like great tits live in communities in which six or seven neighbours surround each territory-holding male. Males appear to benefit from the knowledge that certain individuals occupy specific areas (e.g. Brooks & Falls, 1975), that competitive interactions between two different neighbours have particular outcomes, and that these outcomes are stable over time. We would, therefore, expect an eavesdropping great tit not only to learn that neighbour A was dominant to neighbour B, for example, but also to form the expectation that A was likely to defeat B in all future encounters. More speculatively, because the outcome of territorial interactions are often site specific (reviewed by Bradbury & Vehrencamp, 1998), we would expect eavesdropping tits to learn further that A dominates B in some areas but B dominates A in others. In contrast, the information gained from monitoring neighbours interactions would unlikely be sufficient to allow the eavesdropper to rank all of its neighbours in a linear dominance hierarchy, because not all neighbouring males would come into contact with one another. Such information would be difficult if not impossible to acquire; it might also be of little functional value. In contrast, species that live in large, permanent social groups have a much greater opportunity to monitor the social interactions of many different individuals simultaneously. Monkey species such as baboons Papio cynocephalus, for example, typically live in groups of 80 or more individuals, which include several matrilineal families arranged in a stable, linear dominance rank order (Silk et al., 1999). Offspring assume ranks similar to those of their mothers, and females maintain close bonds with their matrilineal kin throughout their lives. Cutting across these stable long-term relationships based on rank and kinship are more transient bonds: for example, the temporary associations formed between unrelated females whose infants are of similar ages, and the “friendships” formed between adult males and lactating females as an apparent adaptation against infanticide (Palombit et al., 1997, 2001). In order to compete successfully within such groups, it would seem advantageous for individuals to recognize who outranks whom, who is closely bonded to whom, and who is likely to be allied to whom (Harcourt, 1988, 1992; Cheney & Seyfarth, 1990; see below). The ability to adopt a third party`s perspective and discriminate among the social relationships that exist among others would seem to be of great selective benefit. In this chapter, we review evidence for eavesdropping in selected primate species and we consider what sort of information is acquired when one individual observes or listens in on the interactions of others. We then compare eavesdropping by primates with eavesdropping in other animal species, focusing on both potential differences and directions for further research |
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Naguib, M., Amrhein, V., & Kunc, H. P. (2004). Effects of territorial intrusions on eavesdropping neighbors: communication networks in nightingales. Behav. Ecol., 15(6), 1011–1015.
Abstract: Animal communication often occurs in communication networks in which multiple signalers and receivers are within signaling range of each other. In such networks, individuals can obtain information on the quality and motivation of territorial neighbors by eavesdropping on their signaling interactions. In songbirds, extracting information from interactions involving neighbors is thought to be an important factor in the evolution of strategies of territory defense. In a playback experiment with radio-tagged nightingales Luscinia megarhynchos we here demonstrate that territorial males use their familiar neighbors' performance in a vocal interaction with an unfamiliar intruder as a standard for their own response. Males were attracted by a vocal interaction between their neighbor and a simulated stranger and intruded into the neighbor's territory. The more intensely the neighbor had interacted with playback, the earlier the intrusions were made, indicating that males eavesdropped on the vocal contest involving a neighbor. However, males never intruded when we had simulated by a second playback that the intruder had retreated and sang outside the neighbor's territory. These results suggest that territorial males use their neighbors' singing behavior as an early warning system when territorial integrity is threatened. Simultaneous responses by neighboring males towards unfamiliar rivals are likely to be beneficial to the individuals in maintaining territorial integrity.
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Fenton, B., & Ratcliffe, J. (2004). Animal behaviour: eavesdropping on bats. Nature, 429(6992), 612–613.
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Caro, T. M., Graham, C. M., Stoner, C. J., & Vargas, J. K. (2004). Adaptive significance of antipredator behaviour in artiodactyls. Anim. Behav., 67(2), 205–228.
Abstract: We used comparative data to test functional hypotheses for 17 antipredator behaviour patterns in artiodactyls. We examined the literature for hypotheses about auditory and visual signals, defensive behaviour and group-related antipredator behaviour in this taxon and derived a series of predictions for each hypothesis. Next, we documented occurrences of these behaviour patterns and morphological, ecological and behavioural variables for 200 species and coded them in binary format. We then pitted presence of an antipredator behaviour against presence of an independent variable for cervids, bovids and all artiodactyls together using nonparametric tests. Finally, we reanalysed the data using Maddison's (1990, Evolution, 44, 539-557) concentrated-changes tests and a consensus molecular and taxonomic phylogeny. We found evidence that snorting is both a warning signal to conspecifics and a pursuit-deterrent signal, lack of evidence that whistling alerts conspecifics and indications that foot stamping is a visual signal to warn group members. Evidence suggested that tail flagging was a signal to both conspecifics and predators, that bounding, leaping and stotting were used both as a signal and to clear obstacles and that prancing functioned similarly to foot stamping. Analyses of tail flicking, zigzagging and tacking were equivocal. We confirmed that inspection occurs in large groups, freezing enhances crypticity, and species seeking refuge in cliffs tend to be small. Entering water and attacks on predators had few correlates. Finally, group living, a putative antipredator adaptation, was associated with large body size and species living in open habitats, confirming Jarman's (1974, Behaviour, 48, 215-267) classic hypothesis. Bunching and group attack apparently deter predators. Despite limitations, comparative and systematic analyses can bolster adaptive hypotheses and raise new functional explanations for antipredator behaviour patterns in general.
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Proudman, C., Pinchbeck, G., Clegg, P., & French, N. (2004). Equine welfare: risk of horses falling in the Grand National. Nature, 428(6981), 385–386.
Abstract: As in other competitive sports, the famous Grand National steeplechase, which is held at Aintree in the United Kingdom and is watched by 600 million people worldwide, sometimes results in injury. By analysing data from the past 15 Grand National races (consisting of 560 starts by horses), we are able to identify several factors that are significantly associated with failure to complete the race: no previous experience of the course and its unique obstacles, unfavourable ground conditions (too soft or too hard), a large number of runners, and the length of the odds ('starting price'). We also find that there is an increased risk of falling at the first fence and at the jump known as Becher's Brook, which has a ditch on the landing side. Our findings indicate ways in which the Grand National could be made safer for horses and illustrate how epidemiological analysis might contribute to preventing injury in competitive sport.
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Itakura, S. (2004). Gaze Following and Joint Visual Attention in Nonhuman Animals. Jpn. Psychol. Res., 3. Retrieved June 3, 2024, from http://dx.doi.org/10.1111/j.1468-5584.2004.00253.x
Abstract: n this paper, studies of gaze-following and joint visual attention in nonhuman animals are reviewed from the theoretical perspective of Emery (2000). There are many studies of gaze-following and joint visual attention in nonhuman primates. The reports concern not only adult individuals but also the development of these abilities. Studies to date suggest that monkeys and apes are able to follow the gaze of others, but only apes can understand the seeing-knowing relationship with regards to conspecifics in competitive situations. Also, there have recently been some reports of ability to follow the gaze of humans in domestic animals, such as dogs or horses, interacting with humans. These domestic animals are considered to have acquired this ability during their long history of selective breeding by humans. However, we need to clarify social gaze parameters in various species to improve our knowledge of the evolution of how we process others gazing, attention, and mental states.
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