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C Schloegl J Schmidt M Boeckle BM Weiß K Kotrschal 《Proceedings. Biological sciences / The Royal Society》2012,279(1745):4135-4142
Our ability to make logical inferences is considered as one of the cornerstones of human intelligence, fuelling investigations of reasoning abilities in non-human animals. Yet, the evidence to date is equivocal, with apes as the prime candidates to possess these skills. For instance, in a two-choice task, apes can identify the location of hidden food if it is indicated by a rattling noise caused by the shaking of a baited container. More importantly, they also use the absence of noise during the shaking of the empty container to infer that this container is not baited. However, since the inaugural report of apes solving this task, to the best of our knowledge, no comparable evidence could be found in any other tested species such as monkeys and dogs. Here, we report the first successful and instantaneous solution of the shaking task through logical inference by a non-ape species, the African grey parrot. Surprisingly, the performance of the birds was sensitive to the shaking movement: they were successful with containers shaken horizontally, but not with vertical shaking resembling parrot head-bobbing. Thus, grey parrots seem to possess ape-like cross-modal reasoning skills, but their reliance on these abilities is influenced by low-level interferences. 相似文献
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Nga Nguyen Peter J. Fashing Derek A. Boyd Tyler S. Barry Ryan J. Burke C. Barret Goodale Sorrel C.Z. Jones Jeffrey T. Kerby Bryce S. Kellogg Laura M. Lee Carrie M. Miller Niina O. Nurmi Malcolm S. Ramsay Jason D. Reynolds Kathrine M. Stewart Taylor J. Turner Vivek V. Venkataraman Yvonne Knauf Christian Roos Sascha Knauf 《American journal of primatology》2015,77(5):579-594
427.
Many animals are organized into social groups and have to synchronize their activities to maintain group cohesion. Although
activity budgets, habitat constraints, and group properties may impact on behavioural synchrony, little is known regarding
how members of a group reach a consensus on the timing of activities such as foraging bouts. Game theory predicts that pair
partners should synchronize their activities when there is an advantage of foraging together. As a result of this synchronization,
differences in the energetic reserves of the two players develop spontaneously and the individual with lower reserves emerges
as a pacemaker of the synchrony. Here, we studied the behavioral synchrony of pair-living, nocturnal, red-tailed sportive
lemurs (Lepilemur ruficaudatus). We observed 8 pairs continuously for ≥1 annual reproductive cycle in Kirindy Forest, Western Madagascar. During focal observations,
one observer followed the female of a pair and, simultaneously, another observer followed the male. We recorded the location
and behavioral state of the focal individual every 5 min via instantaneous sampling. Although behavioral synchrony of pair
partners appeared to be due mainly to endogenous activity patterns, they actively synchronized when they were in visual contact
(<10 m). Nevertheless, red-tailed sportive lemurs benefit from synchronizing their activity only for 15% of the time, when
they are close together. The lack of an early warning system for predators and weak support for benefits via social information
transfer in combination with energetic constraints may explain why red-tailed sportive lemurs do not spend more time together
and thus reap the benefits of behavioral synchrony. 相似文献
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Anni H?m?l?inen Melanie Dammhahn Fabienne Aujard Manfred Eberle Isabelle Hardy Peter M. Kappeler Martine Perret Susanne Schliehe-Diecks Cornelia Kraus 《Proceedings. Biological sciences / The Royal Society》2014,281(1791)
Classic theories of ageing consider extrinsic mortality (EM) a major factor in shaping longevity and ageing, yet most studies of functional ageing focus on species with low EM. This bias may cause overestimation of the influence of senescent declines in performance over condition-dependent mortality on demographic processes across taxa. To simultaneously investigate the roles of functional senescence (FS) and intrinsic, extrinsic and condition-dependent mortality in a species with a high predation risk in nature, we compared age trajectories of body mass (BM) in wild and captive grey mouse lemurs (Microcebus murinus) using longitudinal data (853 individuals followed through adulthood). We found evidence of non-random mortality in both settings. In captivity, the oldest animals showed senescence in their ability to regain lost BM, whereas no evidence of FS was found in the wild. Overall, captive animals lived longer, but a reversed sex bias in lifespan was observed between wild and captive populations. We suggest that even moderately condition-dependent EM may lead to negligible FS in the wild. While high EM may act to reduce the average lifespan, this evolutionary process may be counteracted by the increased fitness of the long-lived, high-quality individuals. 相似文献
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Eugenia Polizzi di Sorrentino Gabriele Schino Barbara Tiddi Filippo Aureli 《Ethology : formerly Zeitschrift fur Tierpsychologie》2012,118(11):1072-1084
Emotional responses to social interactions and the associated behavioural measures (e.g., self‐directed behaviours, SDBs) have been little studied in New World monkeys, especially in wild settings. In this study, we investigated the factors affecting anxiety in a wild group of tufted capuchin monkeys (Cebus apella nigritus) using self‐scratching (hereafter scratching) as its measure. Scratching was more strongly affected by the social context than by individual characteristics. Indeed, inter‐individual variability was not explained by the age, sex and dominance rank of the monkeys. The monkeys scratched themselves more often when being distant from other group members than when in close proximity with them, suggesting that even short‐distance separation from group members may be an important factor affecting capuchins emotional response. The risk of receiving aggression seemed also to elicit anxiety, as scratching was higher when in proximity to more dominant individuals and females, which were the categories of group members that were more aggressive. By contrast, scratching was lower when in proximity to more secure partners, like kin. Finally, scratching rates following the receipt of aggression were higher than at baseline, indicating a post‐conflict increase in anxiety. Overall, our results contribute to the understanding of the factors affecting emotional responses in capuchin monkeys, confirming and expanding previous findings in other animal species. 相似文献