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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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Behrens, T. E. J., Hunt, L. T., Woolrich, M. W., & Rushworth, M. F. S. (2008). Associative learning of social value. Nature, 456(7219), 245–249.
Abstract: Our decisions are guided by information learnt from our environment. This information may come via personal experiences of reward, but also from the behaviour of social partners1, 2. Social learning is widely held to be distinct from other forms of learning in its mechanism and neural implementation; it is often assumed to compete with simpler mechanisms, such as reward-based associative learning, to drive behaviour3. Recently, neural signals have been observed during social exchange reminiscent of signals seen in studies of associative learning4. Here we demonstrate that social information may be acquired using the same associative processes assumed to underlie reward-based learning. We find that key computational variables for learning in the social and reward domains are processed in a similar fashion, but in parallel neural processing streams. Two neighbouring divisions of the anterior cingulate cortex were central to learning about social and reward-based information, and for determining the extent to which each source of information guides behaviour. When making a decision, however, the information learnt using these parallel streams was combined within ventromedial prefrontal cortex. These findings suggest that human social valuation can be realized by means of the same associative processes previously established for learning other, simpler, features of the environment.
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Milinski, M., & Rockenbach, B. (2008). Human behaviour: Punisher pays. Nature, 452(7185), 297–298.
Abstract: The tendency of humans to punish perceived free-loaders, even at a cost to themselves, is an evolutionary puzzle: punishers perish, and those who benefit the most are those who have never punished at all.
Humans are champions of cooperation. Reciprocity – the idea that, if I help you this time, you'll help me next time1 – is a secret of our success.
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Dreber, A., Rand, D. G., Fudenberg, D., & Nowak, M. A. (2008). Winners don/'t punish. Nature, 452(7185), 348–351.
Abstract: A key aspect of human behaviour is cooperation1, 2, 3, 4, 5, 6, 7. We tend to help others even if costs are involved. We are more likely to help when the costs are small and the benefits for the other person significant. Cooperation leads to a tension between what is best for the individual and what is best for the group. A group does better if everyone cooperates, but each individual is tempted to defect. Recently there has been much interest in exploring the effect of costly punishment on human cooperation8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23. Costly punishment means paying a cost for another individual to incur a cost. It has been suggested that costly punishment promotes cooperation even in non-repeated games and without any possibility of reputation effects10. But most of our interactions are repeated and reputation is always at stake. Thus, if costly punishment is important in promoting cooperation, it must do so in a repeated setting. We have performed experiments in which, in each round of a repeated game, people choose between cooperation, defection and costly punishment. In control experiments, people could only cooperate or defect. Here we show that the option of costly punishment increases the amount of cooperation but not the average payoff of the group. Furthermore, there is a strong negative correlation between total payoff and use of costly punishment. Those people who gain the highest total payoff tend not to use costly punishment: winners don't punish. This suggests that costly punishment behaviour is maladaptive in cooperation games and might have evolved for other reasons.
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Prather, J. F., Peters, S., Nowicki, S., & Mooney, R. (2008). Precise auditory-vocal mirroring in neurons for learned vocal communication. Nature, 451(7176), 305–310.
Abstract: Brain mechanisms for communication must establish a correspondence between sensory and motor codes used to represent
the signal. One idea is that this correspondence is established at the level of single neurons that are active when the
individual performs a particular gesture or observes a similar gesture performed by another individual. Although neurons
that display a precise auditory–vocal correspondence could facilitate vocal communication, they have yet to be identified.
Here we report that a certain class of neurons in the swamp sparrow forebrain displays a precise auditory–vocal
correspondence. We show that these neurons respond in a temporally precise fashion to auditory presentation of certain
note sequences in this songbird’s repertoire and to similar note sequences in other birds’ songs. These neurons display
nearly identical patterns of activity when the bird sings the same sequence, and disrupting auditory feedback does not alter
this singing-related activity, indicating it is motor in nature. Furthermore, these neurons innervate striatal structures
important for song learning, raising the possibility that singing-related activity in these cells is compared to auditory
feedback to guide vocal learning.
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Pesenti, M. E., Spinelli, S., Bezirard, V., Briand, L., Pernollet, J. - C., Tegoni, M., et al. (2008). Structural Basis of the Honey Bee PBP Pheromone and pH-induced Conformational Change. J Mol Biol, 380(1), 158–169.
Abstract: The behavior of insects and their perception of their surroundings are driven, in a large part, by odorants and pheromones. This is especially true for social insects, such as the honey bee, where the queen controls the development and the caste status of the other individuals. Pheromone perception is a complex phenomenon relying on a cascade of recognition events, initiated in antennae by pheromone recognition by a pheromone-binding protein and finishing with signal transduction at the axon membrane level. With to the objective of deciphering this initial step, we have determined the structures of the bee antennal pheromone-binding protein (ASP1) in the apo form and in complex with the main component of the queen mandibular pheromonal mixture, 9-keto-2(E)-decenoic acid (9-ODA) and with nonpheromonal components. In the apo protein, the C terminus obstructs the binding site. In contrast, ASP1 complexes have different open conformations, depending on the ligand shape, leading to different volumes of the binding cavity. The binding site integrity depends on the C terminus (111-119) conformation, which involves the interplay of two factors; i.e. the presence of a ligand and a low pH. Ligand binding to ASP1 is favored by low pH, opposite to what is observed with other pheromone-binding proteins, such as those of Bombyx mori and Anopheles gambiae.
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Li, W., Howard, J. D., Parrish, T. B., & Gottfried, J. A. (2008). Aversive Learning Enhances Perceptual and Cortical Discrimination of Indiscriminable Odor Cues. Science, 319(5871), 1842–1845.
Abstract: Learning to associate sensory cues with threats is critical for minimizing aversive experience. The ecological benefit of associative learning relies on accurate perception of predictive cues, but how aversive learning enhances perceptual acuity of sensory signals, particularly in humans, is unclear. We combined multivariate functional magnetic resonance imaging with olfactory psychophysics to show that initially indistinguishable odor enantiomers (mirror-image molecules) become discriminable after aversive conditioning, paralleling the spatial divergence of ensemble activity patterns in primary olfactory (piriform) cortex. Our findings indicate that aversive learning induces piriform plasticity with corresponding gains in odor enantiomer discrimination, underscoring the capacity of fear conditioning to update perceptual representation of predictive cues, over and above its well-recognized role in the acquisition of conditioned responses. That completely indiscriminable sensations can be transformed into discriminable percepts further accentuates the potency of associative learning to enhance sensory cue perception and support adaptive behavior.
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Li, W., Howard, J. D., Parrish, T. B., & Gottfried, J. A. (2008). Supporting Online Material to: Aversive Learning Enhances Perceptual and Cortical Discrimination of Indiscriminable Odor Cues (Vol. 319).
Abstract: Learning to associate sensory cues with threats is critical for minimizing aversive experience. The ecological benefit of associative learning relies on accurate perception of predictive cues, but how aversive learning enhances perceptual acuity of sensory signals, particularly in humans, is unclear. We combined multivariate functional magnetic resonance imaging with olfactory psychophysics to show that initially indistinguishable odor enantiomers (mirror-image molecules) become discriminable after aversive conditioning, paralleling the spatial divergence of ensemble activity patterns in primary olfactory (piriform) cortex. Our findings indicate that aversive learning induces piriform plasticity with corresponding gains in odor enantiomer discrimination, underscoring the capacity of fear conditioning to update perceptual representation of predictive cues, over and above its well-recognized role in the acquisition of conditioned responses. That completely indiscriminable sensations can be transformed into discriminable percepts further accentuates the potency of associative learning to enhance sensory cue perception and support adaptive behavior.
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Webster, M. M., & Laland, K. N. (2008). Social learning strategies and predation risk: minnows copy only when using private information would be costly. Proc. R. Soc. Lond. B, 275(1653), 2869–2876.
Abstract: Animals can acquire information from the environment privately, by sampling it directly, or socially, through learning from others. Generally, private information is more accurate, but expensive to acquire, while social information is cheaper but less reliable. Accordingly, the 'costly information hypothesis' predicts that individuals will use private information when the costs associated with doing so are low, but that they should increasingly use social information as the costs of using private information rise. While consistent with considerable data, this theory has yet to be directly tested in a satisfactory manner. We tested this hypothesis by giving minnows (Phoxinus phoxinus) a choice between socially demonstrated and non-demonstrated prey patches under conditions of low, indirect and high simulated predation risk. Subjects had no experience (experiment 1) or prior private information that conflicted with the social information provided by the demonstrators (experiment 2). In both experiments, subjects spent more time in the demonstrated patch than in the non-demonstrated patch, and in experiment 1 made fewer switches between patches, when risk was high compared with when it was low. These findings are consistent with the predictions of the costly information hypothesis, and imply that minnows adopt a 'copy-when-asocial-learning-is-costly' learning strategy.
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Parker, M., Redhead, E. S., Goodwin, D., & McBride, S. D. (2008). Impaired instrumental choice in crib-biting horses (Equus caballus). Behav. Brain. Res., 191(1), 137–140.
Abstract: Horses displaying an oral stereotypy were tested on an instrumental choice paradigm to examine differences in learning from non-stereotypic counterparts. Stereotypic horses are known to have dysfunction of the dorsomedial striatum, and lesion studies have shown that this region may mediate response-outcome learning. The paradigm was specifically applied in order to examine learning that requires maintenance of response-outcome judgements. The non-stereotypic horses learned, over three sessions, to choose a more immediate reinforcer, whereas the stereotypic horses failed to do so. This suggests an initial behavioural correlate for dorsomedial striatum dysregulation in the stereotypy phenotype.
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