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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
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
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
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
Nagy, M., Akos, Z., Biro, D., & Vicsek, T. (2010). Hierarchical group dynamics in pigeon flocks. Nature, 464(7290), 890–893.
Abstract: Animals that travel together in groups display a variety of fascinating motion patterns thought to be the result of delicate local interactions among group members1, 2, 3. Although the most informative way of investigating and interpreting collective movement phenomena would be afforded by the collection of high-resolution spatiotemporal data from moving individuals, such data are scarce4, 5, 6, 7 and are virtually non-existent for long-distance group motion within a natural setting because of the associated technological difficulties8. Here we present results of experiments in which track logs of homing pigeons flying in flocks of up to 10 individuals have been obtained by high-resolution lightweight GPS devices and analysed using a variety of correlation functions inspired by approaches common in statistical physics. We find a well-defined hierarchy among flock members from data concerning leading roles in pairwise interactions, defined on the basis of characteristic delay times between birds’ directional choices. The average spatial position of a pigeon within the flock strongly correlates with its place in the hierarchy, and birds respond more quickly to conspecifics perceived primarily through the left eye—both results revealing differential roles for birds that assume different positions with respect to flock-mates. From an evolutionary perspective, our results suggest that hierarchical organization of group flight may be more efficient than an egalitarian one, at least for those flock sizes that permit regular pairwise interactions among group members, during which leader–follower relationships are consistently manifested.
Tricomi, E., Rangel, A., Camerer, C. F., & O/'Doherty, J. P. (2010). Neural evidence for inequality-averse social preferences. Nature, 463(7284), 1089–1091.
Abstract: A popular hypothesis in the social sciences is that humans have social preferences to reduce inequality in outcome distributions because it has a negative impact on their experienced reward1, 2, 3. Although there is a large body of behavioural and anthropological evidence consistent with the predictions of these theories1, 4, 5, 6, there is no direct neural evidence for the existence of inequality-averse preferences. Such evidence would be especially useful because some behaviours that are consistent with a dislike for unequal outcomes could also be explained by concerns for social image7 or reciprocity8, 9, which do not require a direct aversion towards inequality. Here we use functional MRI to test directly for the existence of inequality-averse social preferences in the human brain. Inequality was created by recruiting pairs of subjects and giving one of them a large monetary endowment. While both subjects evaluated further monetary transfers from the experimenter to themselves and to the other participant, we measured neural responses in the ventral striatum and ventromedial prefrontal cortex, two areas that have been shown to be involved in the valuation of monetary and primary rewards in both social and non-social contexts10, 11, 12, 13, 14. Consistent with inequality-averse models of social preferences, we find that activity in these areas was more responsive to transfers to others than to self in the ‘high-pay’ subject, whereas the activity of the ‘low-pay’ subject showed the opposite pattern. These results provide direct evidence for the validity of this class of models, and also show that the brain’s reward circuitry is sensitive to both advantageous and disadvantageous inequality.
Clutton-Brock, T. (2009). Cooperation between non-kin in animal societies. Nature, 462(7269), 51–57.
Abstract: Explanations of cooperation between non-kin in animal societies often suggest that individuals exchange resources or services and that cooperation is maintained by reciprocity. But do cooperative interactions between unrelated individuals in non-human animals really resemble exchanges or are they a consequence of simpler mechanisms? Firm evidence of reciprocity in animal societies is rare and many examples of cooperation between non-kin probably represent cases of intra-specific mutualism or manipulation.
Kihara, H., Nakatani, H., Hiromi, K., & Hon-Nami, K. (1977). Kinetic studies on redox reactions of hemoproteins. I. Reduction of thermoresistant cytochrome c-552 and horse heart cytochrome c by ferrocyanide. Biochim Biophys Acta, 460(3), 480–489.
Abstract: The oxidation-reduction reaction of horse heart cytochrome c and cytochrome c (552, Thermus thermophilus), which is highly thermoresistant, was studied by temperature-jump method. Ferrohexacyanide was used as reductant. (Formula: see text.) Thermodynamic and activation parameters of the reaction obtained for both cytochromes were compared with each other. The results of this showed that (1) the redox potential of cytochrome c-552, + 0.19 V, is markedly less than that of horse heart cytochrome c. (2) deltaHox of cytochrome c-552 is considerably lower than that of horse heart cytochrome c. (3) deltaSox and deltaSred of cytochrome c-552 are more negative than those of horse heart cytochrome c. (4) kred of cytochrome c-552 is much lower than that of horse heart cytochrome c at room temperature.
Kihara, H., Nakatani, H., Hiromi, K., Hon-Nami, K., & Oshima, T. (1977). Kinetic studies on redox reactions of hemoproteins. I. Reduction of thermoresistant cytochrome c-552 and horse heart cytochrome c by ferrocyanide. Biochimica et Biophysica Acta (BBA) – Bioenergetics, 460(3), 480–489.
Abstract: The oxidation-reduction reaction of horse heart cytochrome c and cytochrome c (552, Thermus thermophilus), which is highly thermoresistant, was studied by temperature-jump method. Ferrohexacyanide was used as reductant. Thermodynamic and activation parameters of the reaction obtained for both cytochromes were compared with each other. The results of this showed that (1) the redox potential of cytochrome c-552,+0.19 V, is markedly less than that of horse heart cytochrome c. (2) [up triangle, open]Hox++ of cytochrome c-552 is considerably lower than that of horse heart cytochrome c. (3) [up triangle, open]Hox++ and [up triangle, open]Sred++ of cytoochrome c-552 are more negative than those of horse heart cytochrome c. (4) kred of cytochrome c-552 is much lower than that of horse heart cytochrome c at room temperature.
Harrison, S. A., & Tong, F. (2009). Decoding reveals the contents of visual working memory in early visual areas. Nature, 458(7238), 632–635.
Abstract: Visual working memory provides an essential link between perception and higher cognitive functions, allowing for the active maintenance of information about stimuli no longer in view1, 2. Research suggests that sustained activity in higher-order prefrontal, parietal, inferotemporal and lateral occipital areas supports visual maintenance3, 4, 5, 6, 7, 8, 9, 10, 11, and may account for the limited capacity of working memory to hold up to 3â€“4 items9, 10, 11. Because higher-order areas lack the visual selectivity of early sensory areas, it has remained unclear how observers can remember specific visual features, such as the precise orientation of a grating, with minimal decay in performance over delays of many seconds12. One proposal is that sensory areas serve to maintain fine-tuned feature information13, but early visual areas show little to no sustained activity over prolonged delays14, 15, 16. Here we show that orientations held in working memory can be decoded from activity patterns in the human visual cortex, even when overall levels of activity are low. Using functional magnetic resonance imaging and pattern classification methods, we found that activity patterns in visual areas V1â€“V4 could predict which of two oriented gratings was held in memory with mean accuracy levels upwards of 80%, even in participants whose activity fell to baseline levels after a prolonged delay. These orientation-selective activity patterns were sustained throughout the delay period, evident in individual visual areas, and similar to the responses evoked by unattended, task-irrelevant gratings. Our results demonstrate that early visual areas can retain specific information about visual features held in working memory, over periods of many seconds when no physical stimulus is present.
Ohtsuki, H., Iwasa, Y., & Nowak, M. A. (2009). Indirect reciprocity provides only a narrow margin of efficiency for costly punishment. Nature, 457(7225), 79–82.
Abstract: Indirect reciprocity1, 2, 3, 4, 5 is a key mechanism for the evolution of human cooperation. Our behaviour towards other people depends not only on what they have done to us but also on what they have done to others. Indirect reciprocity works through reputation5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17. The standard model of indirect reciprocity offers a binary choice: people can either cooperate or defect. Cooperation implies a cost for the donor and a benefit for the recipient. Defection has no cost and yields no benefit. Currently there is considerable interest in studying the effect of costly (or altruistic) punishment on human behaviour18, 19, 20, 21, 22, 23, 24, 25. Punishment implies a cost for the punished person. Costly punishment means that the punisher also pays a cost. It has been suggested that costly punishment between individuals can promote cooperation. Here we study the role of costly punishment in an explicit model of indirect reciprocity. We analyse all social norms, which depend on the action of the donor and the reputation of the recipient. We allow errors in assigning reputation and study gossip as a mechanism for establishing coherence. We characterize all strategies that allow the evolutionary stability of cooperation. Some of those strategies use costly punishment; others do not. We find that punishment strategies typically reduce the average payoff of the population. Consequently, there is only a small parameter region where costly punishment leads to an efficient equilibrium. In most cases the population does better by not using costly punishment. The efficient strategy for indirect reciprocity is to withhold help for defectors rather than punishing them.
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.
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.