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Gaunet, F., & Deputte, B. (2011). Functionally referential and intentional communication in the domestic dog: effects of spatial and social contexts. Animal Cognition, 14(6), 849–860.
Abstract: In apes, four criteria are set to explore referential and intentional communication: (1) successive visual orienting between a partner and distant targets, (2) the presence of apparent attention-getting behaviours, (3) the requirement of an audience to exhibit the behaviours, and (4) the influence of the direction of attention of an observer on the behaviours. The present study aimed at identifying these criteria in behaviours used by dogs in communicative episodes with their owner when their toy is out of reach, i.e. gaze at a hidden target or at the owner, gaze alternation between a hidden target and the owner, vocalisations and contacts. In this study, an additional variable was analysed: the position of the dog in relation to the location of the target. Dogs witnessed the hiding of a favourite toy, in a place where they could not get access to. We analysed how dogs engaged in communicative deictic behaviours in the presence of their owner; four heights of the target were tested. To control for the motivational effects of the toy on the dogs’ behaviour and for the referential nature of the behaviours, observations were staged where only the toy or only the owner was present, for one of the four heights. The results show that gazing at the container and gaze alternation were used as functionally referential and intentional communicative behaviours. Behavioural patterns of dog position, the new variable, fulfilled the operational criteria for functionally referential behaviour and a subset of operational criteria for intentional communication: the dogs used their own position as a local enhancement signal. Finally, our results suggest that the dogs gazed at their owner at optimal locations in the experimental area, with respect to the target height and their owner’s (or their own) line of gaze.
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Peeters, M., Sulon, J., Beckers, J. - F., Ledoux, D., & Vandenheede, M. (2011). Comparison between blood serum and salivary cortisol concentrations in horses using an adrenocorticotropic hormone challenge. Equine Veterinary Journal, 43(4), 487–493.
Abstract: Reasons for performing study: In horses, serum cortisol concentration is considered to provide an indirect measurement of stress. However, it includes both free and bound fractions. The sampling method is also invasive and often stressful. This is not the case for salivary cortisol, which is collected using a more welfare-friendly method and represents a part of the free cortisol fraction, which is the biologically active form. Objectives: To compare salivary and serum cortisol assays in horses, in a wide range of concentrations, using an adrenocorticotropic hormone (ACTH) stimulation test, in order to validate salivary cortisol for stress assessment in horse. Methods: In 5 horses, blood samples were drawn using an i.v. catheter. Saliva samples were taken using swabs. Cortisol was assayed by radioimmunoassay. All data were treated with a regression method, which pools and analyses data from multiple subjects for linear analysis. Results: Mean ± s.d. cortisol concentrations measured at rest were 188.81 ± 51.46 nmol/l in serum and 1.19 ± 0.54 nmol/l in saliva. They started increasing immediately after ACTH injection and peaks were reached after 96 ± 16.7 min in serum (356.98 ± 55.29 nmol/l) and after 124 ± 8.9 min in saliva (21.79 ± 7.74 nmol/l, P<0.05). Discharge percentages were also different (225% in serum and 2150% in saliva, P<0.05). Correlation between serum and salivary cortisol concentrations showed an adjusted r2= 0.80 (P<0.001). The strong link between serum and salivary cortisol concentrations was also estimated by a regression analysis. Conclusions: The reliability of both RIAs and regression found between serum and salivary cortisol concentrations permits the validation of saliva-sampling as a noninvasive technique for cortisol level assessment in horses.
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Krueger K., F. K., Byrne R. (2011). The use of sensory laterality for indicating emotional and cognitive reactions on environmental stimuli in animals [Die sensorische Lateralität als Indikator für emotionale und kognitive Reaktionen auf Umweltreize beim Tier]. In M. Erhard, U. Pollmann, B. Puppe, K. Reiter, & S. Waiblinger (Eds.), Current research in applied ethology [Aktuelle Arbeiten zur artgemäßen Tierhaltung (pp. 13–23). Darmstadt: KTBL.
Abstract: Summary
Many animals are lateralized when using sensory organs such as the eyes, ears or nostrils. Sensory laterality is not, as previously believed, caused by adjustment to motor laterality, but rather by one sided information processing in the particular brain hemi-spheres. While the right hemisphere predominantly analyses emotional information, the left hemisphere governs controlled rational, cognitive decisions. Since the brain hemi-spheres are largely connected with contralateral sensory organs, it is possible to infer how the information may be being interpreted by the side of preferred eye, ear or nostril used. The left eye usually dominates in emotional situations, i.e. fear or positive ex-citement, and the right eye in rational situations. Moreover, laterality increases when animals are stressed, e.g. when animals are confronted with anthropogenic or natural factors they can not handle, such as unsuitable housing or training conditions or un-avoidable predation pressure and social competition. A strong or increasing laterality could therefore potentially indicate welfare issues.
Zusammenfassung
Viele Tiere zeigen eine eindeutige sensorische Lateralität, sprich sie benutzen bevor-zugt ein Auge, ein Ohr, oder eine Nüster zur Aufnahme von Sinneseindrücken. Dies korreliert in den meisten Fällen nicht mit der motorischen Lateralität, sondern wird viel mehr durch die einseitige Verarbeitung von Informationen in den jeweiligen Gehirnhe-misphären bedingt. So werden emotionale Reaktionen von der rechten, reaktiven Ge-hirnhemisphäre und rationale Reaktionen von der linken, kognitiven Gehirnhemisphäre gesteuert. Da die Gehirnhälften zum Großen Teil mit den kontrolateralen Sinnesorga-nen verbunden sind lässt die Seite mit welcher Sinneseindrücke aufgenommen werden Schlüsse auf deren Informationsgehalt zu. So zeigen Tiere bei linksseitiger Aufnahme von Sinneseindrücken vermehrt reaktive, emotionalen Reaktionen, wie etwa bei Angst oder freudige Erregung, und bei rechtsseitig aufgenommene Sinneseindrücke eher rationales, gesteuertes Verhalten. Zudem verstärkt sich die sensorische Lateralität wenn Tiere Stress erfahren, sprich wenn sie wiederholt mit Situationen anthropogenen oder natürlichen Ursprungs konfrontiert werden denen sie nicht gewachsen sind, wie etwa bei unpassenden Haltungs- und Trainingsbedingungen, oder bei unausweichli-chem Raubtierdruck und sozialer Konkurrenz. Eine stark ausgeprägte, zunehmende sensorische Lateralität kann daher auf ein beeinträchtigtes Wohlergehen der Tiere hinweisen.
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Noy, L., Dekel, E., & Alon, U. (2011). The mirror game as a paradigm for studying the dynamics of two people improvising motion together. Proceedings of the National Academy of Sciences, .
Abstract: Joint improvisation is the creative action of two or more people without a script or designated leader. Examples include improvisational theater and music, and day-to-day activities such as conversations. In joint improvisation, novel action is created, emerging from the interaction between people. Although central to creative processes and social interaction, joint improvisation remains largely unexplored due to the lack of experimental paradigms. Here we introduce a paradigm based on a theater practice called the mirror game. We measured the hand motions of two people mirroring each other at high temporal and spatial resolution. We focused on expert actors and musicians skilled in joint improvisation. We found that players can jointly create novel complex motion without a designated leader, synchronized to less than 40 ms. In contrast, we found that designating one player as leader deteriorated performance: The follower showed 2–3 Hz oscillation around the leader's smooth trajectory, decreasing synchrony and reducing the range of velocities reached. A mathematical model suggests a mechanism for these observations based on mutual agreement on future motion in mirrored reactive–predictive controllers. This is a step toward understanding the human ability to create novelty by improvising together.
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Melis, A. P., Warneken, F., Jensen, K., Schneider, A. - C., Call, J., & Tomasello, M. (2011). Chimpanzees help conspecifics obtain food and non-food items. Proceedings of the Royal Society B: Biological Sciences, 278(1710), 1405–1413.
Abstract: Chimpanzees (Pan troglodytes) sometimes help both humans and conspecifics in experimental situations in which immediate selfish benefits can be ruled out. However, in several experiments, chimpanzees have not provided food to a conspecific even when it would cost them nothing, leading to the hypothesis that prosociality in the food-provisioning context is a derived trait in humans. Here, we show that chimpanzees help conspecifics obtain both food and non-food items—given that the donor cannot get the food herself. Furthermore, we show that the key factor eliciting chimpanzees' targeted helping is the recipients' attempts to either get the food or get the attention of the potential donor. The current findings add to the accumulating body of evidence that humans and chimpanzees share the motivation and skills necessary to help others in situations in which they cannot selfishly benefit. Humans, however, show prosocial motives more readily and in a wider range of contexts.
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Gesquiere, L. R., Learn, N. H., Simao, M. C. M., Onyango, P. O., Alberts, S. C., & Altmann, J. (2011). Life at the Top: Rank and Stress in Wild Male Baboons. Science, 333(6040), 357–360.
Abstract: In social hierarchies, dominant individuals experience reproductive and health benefits, but the costs of social dominance remain a topic of debate. Prevailing hypotheses predict that higher-ranking males experience higher testosterone and glucocorticoid (stress hormone) levels than lower-ranking males when hierarchies are unstable but not otherwise. In this long-term study of rank-related stress in a natural population of savannah baboons (Papio cynocephalus), high-ranking males had higher testosterone and lower glucocorticoid levels than other males, regardless of hierarchy stability. The singular exception was for the highest-ranking (alpha) males, who exhibited both high testosterone and high glucocorticoid levels. In particular, alpha males exhibited much higher stress hormone levels than second-ranking (beta) males, suggesting that being at the very top may be more costly than previously thought.
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Steidele, N. (2011). Beobachtungen einer Przewalski-Junggesellenherde im Jahresverlauf unter besonderer Berücksichtigung von Ruheverhalten und Rangordnung.
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Neumann, C., Duboscq, J., Dubuc, C., Ginting, A., Irwan, A. M., Agil, M., et al. (2011). Assessing dominance hierarchies: validation and advantages of progressive evaluation with Elo-rating. Animal Behaviour, 82(4), 911–921.
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Sankey, C., Henry, S., Clouard, C., Richard-Yris, M. - A., & Hausberger, M. (2011). Asymmetry of behavioral responses to a human approach in young naive vs. trained horses. Physiology & Behavior, 104(3), 464–468.
Abstract: The aim of this study was to investigate the impact of training experience on young horses (Equus caballus)’ lateralized responses to an approaching human. The results show that the one year old untrained horses display asymmetrical responses to an approaching human, with more negative reactions (escapes, threats) when approached from the left side, while approaches towards the right shoulder elicited more positive behaviors. On the contrary, two years old trained horses reacted equally positively to approaches and contact on both sides. Our findings support those of previous studies investigating a link between emotionality and laterality and confirm the role of the left hemisphere in the processing of novel or negative stimuli. Moreover, the data underline the impact work and training can have on this laterality in horses.
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Pruvost, M., Bellone, R., Benecke, N., Sandoval-Castellanos, E., Cieslak, M., Kuznetsova, T., et al. (2011). Genotypes of predomestic horses match phenotypes painted in Paleolithic works of cave art. Proceedings of the National Academy of Sciences, 108(46), 18626–18630.
Abstract: Archaeologists often argue whether Paleolithic works of art, cave paintings in particular, constitute reflections of the natural environment of humans at the time. They also debate the extent to which these paintings actually contain creative artistic expression, reflect the phenotypic variation of the surrounding environment, or focus on rare phenotypes. The famous paintings “The Dappled Horses of Pech-Merle,” depicting spotted horses on the walls of a cave in Pech-Merle, France, date back ~25,000 y, but the coat pattern portrayed in these paintings is remarkably similar to a pattern known as “leopard” in modern horses. We have genotyped nine coat-color loci in 31 predomestic horses from Siberia, Eastern and Western Europe, and the Iberian Peninsula. Eighteen horses had bay coat color, seven were black, and six shared an allele associated with the leopard complex spotting (LP), representing the only spotted phenotype that has been discovered in wild, predomestic horses thus far. LP was detected in four Pleistocene and two Copper Age samples from Western and Eastern Europe, respectively. In contrast, this phenotype was absent from predomestic Siberian horses. Thus, all horse color phenotypes that seem to be distinguishable in cave paintings have now been found to exist in prehistoric horse populations, suggesting that cave paintings of this species represent remarkably realistic depictions of the animals shown. This finding lends support to hypotheses arguing that cave paintings might have contained less of a symbolic or transcendental connotation than often assumed.
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