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Okamoto, S., Tomonaga, M., Ishii, K., Kawai, N., Tanaka, M., & Matsuzawa, T. (2002). An infant chimpanzee (Pan troglodytes) follows human gaze. Anim. Cogn., 5(2), 107–114.
Abstract: The ability of non-human primates to follow the gaze of other individuals has recently received much attention in comparative cognition. The aim of the present study was to investigate the emergence of this ability in a chimpanzee infant. The infant was trained to look at one of two objects, which an experimenter indicated by one of four different cue conditions: (1) tapping on the target object with a finger; (2) pointing to the target object with a finger; (3) gazing at the target object with head orientation; or (4) glancing at the target object without head orientation. The subject was given food rewards independently of its responses under the first three conditions, so that its responses to the objects were not influenced by the rewards. The glancing condition was tested occasionally, without any reinforcement. By the age of 13 months, the subject showed reliable following responses to the object that was indicated by the various cues, including glancing alone. Furthermore, additional tests clearly showed that the subject's performance was controlled by the “social” properties of the experimenter-given cues but not by the non-social, local-enhancing peripheral properties.
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Okanoya, K., Ikebuchi, M., Uno, H., & Watanabe, S. (2001). Left-side dominance for song discrimination in Bengalese finches (Lonchura striata var. domestica). Anim. Cogn., 4(3), 241–245.
Abstract: Male Bengalese finches are left-side dominant for the motor control of song in the sensorimotor nucleus (the high vocal center, or HVc) of the telencephalon. We examined whether perceptual discrimination of songs might also be lateralized in this species. Twelve male Bengalese finches were trained by operant conditioning to discriminate between a Bengalese finch song and a zebra finch song. Before training, the left HVc was lesioned in four birds and the right HVc was lesioned in four other birds. The remaining four birds were used as controls without surgery. Birds with a left HVc lesion required significantly more time to learn to discriminate between the two songs than did birds with a right HVc lesion or intact control birds. These results suggest that the left HVc is not only dominant for the motor control of song, but also for the perceptual discrimination of song.
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Oliva, J. L., Rault, J. - L., Appleton, B., & Lill, A. (2015). Oxytocin enhances the appropriate use of human social cues by the domestic dog (Canis familiaris) in an object choice task. Anim. Cogn., 18(3), 767–775.
Abstract: It has been postulated that the neuropeptide, oxytocin, is involved in human–dog bonding. This may explain why dogs, compared to wolves, are such good performers on object choice tasks, which test their ability to attend to, and use, human social cues in order to find hidden food treats. The objective of this study was to investigate the effect of intranasal oxytocin administration, which is known to increase social cognition in humans, on domestic dogs’ ability to perform such a task. We hypothesised that dogs would perform better on the task after an intranasal treatment of oxytocin. Sixty-two (31 males and 31 females) pet dogs completed the experiment over two different testing sessions, 5–15 days apart. Intranasal oxytocin or a saline control was administered 45 min before each session. All dogs received both treatments in a pseudo-randomised, counterbalanced order. Data were collected as scores out of ten for each of the four blocks of trials in each session. Two blocks of trials were conducted using a momentary distal pointing cue and two using a gazing cue, given by the experimenter. Oxytocin enhanced performance using momentary distal pointing cues, and this enhanced level of performance was maintained over 5–15 days time in the absence of oxytocin. Oxytocin also decreased aversion to gazing cues, in that performance was below chance levels after saline administration but at chance levels after oxytocin administration.
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Osthaus, B., Lea, S. E. G., & Slater, A. M. (2005). Dogs (Canis lupus familiaris) fail to show understanding of means-end connections in a string-pulling task. Anim. Cogn., 8(1), 37–47.
Abstract: Domestic dogs (Canis lupus familiaris) were tested in four experiments for their understanding of means-end connections. In each of the experiments, the dogs attempted to retrieve a food treat that could be seen behind a barrier and which was connected, via string, to a within-reach wooden block. In the experiments, either one or two strings were present, but the treat was attached only to one string. Successful retrieval of the treat required the animals to pull the appropriate string (either by pawing or by grasping the wooden block in their jaws) until the treat emerged from under the barrier. The results showed that the dogs were successful if the treat was in a perpendicular line to the barrier, i.e. straight ahead, but not when the string was at an angle: in the latter condition, the typical response was a proximity error in that the dogs pawed or mouthed at a location closest in line to the treat. When two strings that crossed were present, the dogs tended to pull on the wrong string. The combined results from the experiments show that, although dogs can learn to pull on a string to obtain food, they do not spontaneously understand means-end connections involving strings.
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Osthaus, B., Marlow, D., & Ducat, P. (2010). Minding the gap: spatial perseveration error in dogs. Anim. Cogn., 13(6), 881-885.
Abstract: We investigated a combination of perseveration and detour behaviour in 50 domestic dogs (Canis familiaris). They were required to make a detour through a gap at one end of a straight barrier in order to reach a target. After one, two, three or four repeats, the gap was moved to the opposite end of the barrier, and the detour behaviour of the dogs was recorded. Although the dogs could solve simple detour tasks (80% correct in the first trial), they committed a perseveration error of following the previously learned route despite the clearly visible change in the location of the gap. This ‘misbehaviour’ occurred in 29 of 30 dogs after only two learning trials. They never reached a 100% correct performance level again even after four runs through the second gap location. The results suggest that dogs are reluctant to unlearn acquired spatial motor responses and reinforced navigation, which has important implications for experimental design, everyday dog training and our understanding of their mental capacities.
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Ottoni, E., de Resende, B., & Izar, P. (2006). Erratum. Anim. Cogn., 9(2), 156.
Abstract: Without Abstract
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Ottoni, E. B., de Resende, B. D., & Izar, P. (2005). Watching the best nutcrackers: what capuchin monkeys (Cebus apella) know about others' tool-using skills. Anim. Cogn., 8(4), 215–219.
Abstract: The present work is part of a decade-long study on the spontaneous use of stones for cracking hard-shelled nuts by a semi-free-ranging group of brown capuchin monkeys (Cebus apella). Nutcracking events are frequently watched by other individuals--usually younger, less proficient, and that are well tolerated to the point of some scrounging being allowed by the nutcracker. Here we report findings showing that the choice of observational targets is an active, non-random process, and that observers seem to have some understanding of the relative proficiency of their group mates, preferentially watching the more skilled nutcrackers, which enhances not only scrounging payoffs, but also social learning opportunities.
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Palleroni, A., Hauser, M., & Marler, P. (2005). Do responses of galliform birds vary adaptively with predator size? Anim. Cogn., 8(3), 200–210.
Abstract: Past studies of galliform anti-predator behavior show that they discriminate between aerial and ground predators, producing distinctive, functionally referential vocalizations to each class. Within the category of aerial predators, however, studies using overhead models, video images and observations of natural encounters with birds of prey report little evidence that galliforms discriminate between different raptor species. This pattern suggests that the aerial alarm response may be triggered by general features of objects moving in the air. To test whether these birds are also sensitive to more detailed differences between raptor species, adult chickens with young were presented with variously sized trained raptors (small, intermediate, large) under controlled conditions. In response to the small hawk, there was a decline in anti-predator aggression and in aerial alarm calling as the young grew older and less vulnerable to attack by a hawk of this size. During the same developmental period, responses to the largest hawk, which posed the smallest threat to the young at all stages, did not change; there were intermediate changes at this time in response to the middle-sized hawk. Thus the anti-predator behavior of the adult birds varied in an adaptive fashion, changing as a function of both chick age and risk. We discuss these results in light of current issues concerning the cognitive mechanisms underlying alarm calling behavior in animals.
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Palmer, M. E., Calve, M. R., & Adamo, S. A. (2006). Response of female cuttlefish Sepia officinalis (Cephalopoda) to mirrors and conspecifics: evidence for signaling in female cuttlefish. Anim. Cogn., 9(2), 151–155.
Abstract: Cuttlefish have a large repertoire of body patterns that are used for camouflage and interspecific signaling. Intraspecific signaling by male cuttlefish has been well documented but studies on signaling by females are lacking. We found that females displayed a newly described body pattern termed Splotch toward their mirror image and female conspecifics, but not to males, prey or inanimate objects. Female cuttlefish may use the Splotch body pattern as an intraspecific signal, possibly to reduce agonistic interactions. The ability of females to produce a consistent body pattern in response to conspecifics and mirrors suggests that they can recognize same-sex conspecifics using visual cues, despite the lack of sexual dimorphism visible to human observers.
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Parejo, D., & Aviles, J. M. (2007). Do avian brood parasites eavesdrop on heterospecific sexual signals revealing host quality? A review of the evidence. Anim. Cogn., 10(2), 81–88.
Abstract: Eavesdropping can be defined as the extraction of information from the interactions between other individuals. It provides a relatively cheap way of gathering relevant information for fitness enhancement. Here, we propose that obligate avian brood parasites, which always lay their eggs in foreign nests of individuals of other species, may eavesdrop on their host sexual signals to locate nests of high quality individuals in which to lay their parasitic eggs. Sexual signal variation can honestly signal parental quality. Thus, by eavesdropping on sexual signals, parasites may select high quality foster parents for their own offspring. Such a use of sexual signals within host populations by brood parasites differs from signal exploitation theory that proposes that parasite only use signals to locate potential host independently from signaller quality. Here, we review the avian literature concerning host choice within a host species by obligate avian brood parasites and find evidence for host selection within individuals of a host species on the basis of cues potentially functioning as sexually selected traits, or at least revealing parental abilities. We have also found support for the existence of benefits linked to host selection by avian brood parasites. Finally, one study reported on the attenuation of a sexual ornament in host populations under strong pressure by brood parasites. Most of these findings have been interpreted as evidence for host selection by avian brood parasites based on the conspicuousness of sexual signals. We suggest, however, that these findings may in fact reveal eavesdropping on host signalling performance by brood parasites which would use the information extracted to choose the better individuals among conspecifics of a given host. This provides a new perspective for the study of host selection in obligate brood parasites, and raises interesting questions for the study of animal cognition that would deserve experimental studies.
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