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SYLVAIN GAGNON, F. R. A. N. C. O. I. S. Y. D. O. R. E. (1993). Search behavior of dogs (Canis familiaris) in invisible displacement problems. Anim Learn. & Behav., 21(3), 246–254.
Abstract: Gagnon and Dor (1992) showed that domestic dogs are able to solve a Piagetian object permanence
task called the invisible displacement problem. A toy is hidden in a container which is moved behind a screen where the toy is removed and left. Dogs make more errors in these problems than they do in visible displacement tests, in which the object is hidden directly behind the target screen. In Experiment 1, we examinedcomponents ofthe standard procedure of invisible displacements that may make encoding or retention of the hiding location more difficult than it is in visible displacements. In Experiment 2, we compared dogs performances in visible and invisible displacement problems when delays of 0, 10, and 20 sec were introduced between the objects final disappearance and the subjects release. The results revealed that dogs poorer performance in invisible displacement tests is related to the complex sequence of events that have to be encoded or remembered as well as to a difficulty in representing the position change that is signaled, but not directly perceived. |
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Ord, T. J., & Evans, C. S. (2002). Interactive video playback and opponent assessment in lizards. Behav. Process., 59(2), 55–65.
Abstract: Video playback has been used to explore many issues in animal communication, but the scope of this work has been constrained by the lack of stimulus-subject interaction. In many natural contexts, each participant's signalling behaviour is dependent from moment-to-moment on that of the other. Analyses of acoustic communication demonstrate the value of reproducing such social contingencies. We assessed the utility of interactive playback for studies of visual signalling by comparing the responses of male Jacky dragons, Amphibolurus muricatus, to interactive and non-interactive digital video playbacks of a life-sized conspecific. Displays produced by lizards in the interactive condition had the effect of suppressing the aggressive display of their simulated opponent. Each stimulus sequence generated during an interactive playback was subsequently played to a size-matched control animal. Males that could interact with the video stimulus responded principally with aggressive displays, while those that could not produced a mixture of aggressive and appeasement signals. Adding a degree of receiver responsiveness is hence sufficient to alter the type of signal evoked, even when video stimuli are physically identical. Interactive playback permits the experimental study of a broader range of theoretical topics and can enhance the realism of video stimuli.
Keywords: Animal communication; Display; Lizard; Playback; Visual signal
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Ord, T. J., Peters, R. A., Evans, C. S., & Taylor, A. J. (2002). Digital video playback and visual communication in lizards. Anim. Behav., 63(5), 879–890.
Abstract: Experimental analyses of dynamic visual signals have to overcome the technical obstacle of reproducing complex motor patterns such as those found in courtship and threat displays. Video playback offers a potential solution to this problem, but it has recently been criticized because of sensory differences between humans and nonhuman animals, which suggest that video stimuli might be perceived as deficient relative to live conspecifics. Quantitative comparisons are therefore necessary to determine whether video sequences reliably evoke natural responses. Male Jacky dragons, Amphibolurus muricatus, compete for territories using complex displays delivered in a rapid stereotyped sequence. We evaluated video playback as a technique for studying this visual signal. Digital video sequences depicting a life-sized displaying male were indistinguishable from live male conspecifics in the rate and structure of aggressive displays evoked. Other measures of social behaviour suggested that video stimuli were more effective in this context. Lizards produced significantly more appeasement displays and had higher rates of substrate licking and locomotor activity in response to video playback than to confined male opponents, which failed to produce aggressive displays. Lizards tracked temporal changes in the display rate of video stimuli and were also sensitive to individual differences in morphology and behaviour between video exemplars. These results show that video stimuli are appropriate for the experimental analysis of Jacky dragon aggressive displays. We compare the potential shortcomings of video playback with those of other techniques and conclude that no approach offers a panacea, but that several have complementary characteristics. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.
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Goncalves, D. M., Oliveira, R. F., Korner, K., Poschadel, J. R., & Schlupp, I. (2000). Using video playbacks to study visual communication in a marine fish, Salaria pavo. Anim. Behav., 60(3), 351–357.
Abstract: Video playbacks have been successfully applied to the study of visual communication in several groups of animals. However, this technique is controversial as video monitors are designed with the human visual system in mind. Differences between the visual capabilities of humans and other animals will lead to perceptually different interpretations of video images. We simultaneously presented males and females of the peacock blenny, Salaria pavo, with a live conspecific male and an online video image of the same individual. Video images failed to elicit appropriate responses. Males were aggressive towards the live male but not towards video images of the same male. Similarly, females courted only the live male and spent more time near this stimulus. In contrast, females of the gynogenetic poecilid Poecilia formosa showed an equal preference for a live and video image of a P. mexicana male, suggesting a response to live animals as strong as to video images. We discuss differences between the species that may explain their opposite reaction to video images.
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Kaminski, J., Riedel, J., Call, J., & Tomasello, M. (2005). Domestic goats, Capra hircus, follow gaze direction and use social cues in an object choice task. Anim. Behav., 69(1), 11–18.
Abstract: Gaze following is a basic social cognitive skill with many potential benefits for animals that live in social groups. At least five primate species are known to follow the gaze of conspecifics, but there have been no studies on gaze following in other mammals. We investigated whether domestic goats can use the gaze direction of a conspecific as a cue to find food. They were able to do this, at a level comparable to that of primates. In a second experiment, we tested goats' ability to use gaze and other communicative cues given by a human in a so-called object choice situation. An experimenter hid food out of sight of the subject under one of two cups. After baiting the cup the experimenter indicated the location of the food to the subject by using different cues. The goats used communicative cues (touching and pointing) but not gaze by itself. Since domestic dogs are very skilled in this task, whereas wolves are not, one hypothesis is that the use of communicative cues in the object choice task is a side-effect of domestication.
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Nathan J. Emery. (2005). The Evolution of Social Cognition. In The Cognitive Neuroscience of Social BehaviourGarten. Psychology Press.
Abstract: Although this bookis focusedon the cognitive neuroscience ofhuman social behaviour, an
understandingofsocial cognition in non-human animals is critical for unravellingthe neural basis of social cognition in humans as well as the selective pressures that have shapedthe evolution ofcomplex social cognition. Thanks to methodological limitations, we know little about the relationships between certain biochemical andelectrophysiological properties ofthe human brain andhow theycompute the behaviour andmental states ofother individuals. Traditional techniques for examiningneural function in humans, such as event-relatedpotentials (ERP),positron emission tomography(PET),and functional magnetic resonance imaging(fMRI),are constrainedbythe fact that subjects are placed either into an immoveable scanner with a lot ofbackgroundnoise or wiredup with dozens of electrodes that are sensitive to slight movements. The possibilityofscanningor recordingbrain waves from two individuals that are physicallyinteractingsociallyis technicallyimpossible at present (however, see Montague et al, 2002 for a new methodfor simultaneouslyscanningtwo individuals interactingvia a computer). The onlywayto understandthe neurocognitive architecture ofhuman social behaviour is to examine similar social processes in both human andnon-human animal minds andmake comparisons at the species level. An additional argument is that traditional human socio-cognitive tasks are dependent on the use ofstories, cartoons andverbal cues andinstructions (Heberlein & Adolphs, this volume)which themselves will elicit specific neural responses that have to be eliminatedfrom neural responses specificallyrelatedto mindreading. Therefore, the development ofnon-verbal tasks wouldprovide a breakthrough for studies in non-linguistic animals, pre-verbal human infants andhuman cognitive neuroimaging. |
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Itakura, S. (2004). Gaze Following and Joint Visual Attention in Nonhuman Animals. Jpn. Psychol. Res., 3. Retrieved June 23, 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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Hare, B., & Tomasello, M. (2005). Human-like social skills in dogs? Trends. Cognit. Sci., 9(9), 439–444.
Abstract: Domestic dogs are unusually skilled at reading human social and communicative behavior--even more so than our nearest primate relatives. For example, they use human social and communicative behavior (e.g. a pointing gesture) to find hidden food, and they know what the human can and cannot see in various situations. Recent comparisons between canid species suggest that these unusual social skills have a heritable component and initially evolved during domestication as a result of selection on systems mediating fear and aggression towards humans. Differences in chimpanzee and human temperament suggest that a similar process may have been an important catalyst leading to the evolution of unusual social skills in our own species. The study of convergent evolution provides an exciting opportunity to gain further insights into the evolutionary processes leading to human-like forms of cooperation and communication.
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Digweed, S. M., Fedigan, L. M., & Rendall, D. (2005). Variable specificity in the anti-predator vocalizations and behaviour of the white-faced capuchin, Cebus capucinus. Behaviour, 142(8). Retrieved June 23, 2024, from http://dx.doi.org/10.1163/156853905774405344
Abstract: (Accepted: 23 June 2005)
Summary Much research in animal communication is aimed at understanding the functional design features of animal vocal signals. Our detailed analyses of the vocalizations and behavioural responses elicited in white-faced capuchins by predators and other disturbances point to two call variants that differ modestly in their acoustic structure and that are accompanied by functionally distinct behavioural responses. The first variant is given exclusively to avian predators and is almost invariably accompanied by the monkeys immediate descent from the treetops where it is most vulnerable; therefore, we label this call variant the aerial predator alarm?. The second variant, that differs only slightly but noticeably from the first, is given to a wide range of snakes and mammals, including a range of species that represent no predatory threat to the monkeys. This second call is also associated with more variable responses from calling monkeys, from delayed retreat from the source of disturbance, to active approach, inspection, and sometimes mobbing of the animal involved. We therefore label this variant more generally as an “alerting call”. Although some other primate species show a more diverse system of anti-predator calls, and the capuchins themselves may yet be found to produce a greater variety of calls, a system of two call variants with varying degrees of predator specificity and behavioural response is not uncommon among primates and appears functionally appropriate for capuchins. The basic structure of the alerting call allows conspecific listeners to localize the caller and the source of disturbance readily, thereby allowing listeners to approach and assist in mobbing in cases where the disturbance warrants it, or to avoid the area in cases where the disturbance is identified as a predatory threat. Conversely, the aerial predator alarm is inherently less localizable and therefore conveys the |
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Dunbar, R. (2003). Evolution of the social brain. Science, 302(5648), 1160–1161.
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