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Ray, E. D., Gardner, M. R., & Heyes, C. M. (2000). Seeing how it's done: matching conditions for observer rats (Rattus norvegicus) in the bidirectional control. Anim. Cogn., 3(3), 147–157.
Abstract: In an attempt to increase the reliability of the demonstrator-consistent responding effect produced in the bidirectional control procedure, experiments 1-4 sought conditions that would magnify the matching effect. The aim was to produce a robust demonstrator-consistent responding effect in order that future analytic experiments could investigate the psychological processes responsible for this effect. The joystick responses of observer rats trained using the standard bidirectional control procedure parameters were compared with those of observers subject to conditions identified in the social learning literature as favourable for imitation. Unlike mice, observer rats in experiments 1 a and 1 b tended to push a joystick in the same direction as their demonstrators when the demonstrators were either familiar or unfamiliar males and females. Comparable demonstrator-consistent responding occurred following observation of a standard and a salient joystick response (experiment 2). Experiment 3 showed that the discriminative accuracy of a demonstrator's responding was important for matching behaviour, and suggested that matching might be enhanced with more than the conventional single observation session. Experiment 4 confirmed that the bidirectional control effect is sensitive to the amount of observational experience; after six observation sessions, demonstrator-inconsistent responding occurs. The results of experiments 1-3 are, and those of experiment 4 are not, compatible with the hypothesis that demonstrator-consistent responding in the bidirectional control is caused by olfactory cues deposited by demonstrators on the joystick.
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Rasa, O. A. E. (1998). To stay or to leave? Decision rules for partner species relocation in two symbiotic pairs of desert beetles. Anim. Cogn., 1(1), 47–54.
Abstract: Four nocturnal Kalahari desert tenebrionid beetles live in closely associated species pairs. The larger member of each pair, Parastizopus and Gonopus, are the primary burrowers while their smaller associates, Eremostibes and Herpiscius, inhabit the burrows with them and feed on detritus the larger beetles carry in. During summer drought, the two large species have different emergence times, surface activity patterns (vagilities) and different probabilities that burrows will be reoccupied before sunrise or remain empty for longer periods. Because their partners leave the burrows, the smaller species must make a decision either to stay in the expectation of a burrow being reinhabited, or leave and locate a new partner. The vagility and burrow fidelity of the associating species were studied using marked individuals in free-living populations. Field inclusion/exclusion experiments to test what influences the decision process showed that neither continual partner presence nor food induced the smaller beetles to remain. Different percentages, depending on species, left overnight. For both associates, these proportions corresponded exactly to the probability that the burrow would not be inhabited by their partner species the next day. Neither species predicted the probability of burrow reoccupation after a short vacancy and adopted a “waiting” strategy.
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Range, F., Horn, L., Bugnyar, T., Gajdon, G., & Huber, L. (2009). Social attention in keas, dogs, and human children. Anim. Cogn., 12(1), 181–192.
Abstract: Abstract: Understanding animals" abilities to cooperate with and learn from each other has been an active field of research in recent years. One important basis for all types of social interactions is the disposition of animals to pay attention to each other-a factor often neglected in discussions and experiments. Since attention differs between species as well as between individuals, it is likely to influence the amount and type of information different species and/or observers may extract from conspecifics in any given situation. Here, we carried out a standardized comparative study on attention towards a model demonstrating food-related behavior in keas, dogs and children. In a series of experimental sessions, individuals watched different conspecific models while searching, manipulating and feeding. Visual access to the demonstration was provided by two observation holes, which allowed us to determine exactly how often and for how long observers watched the model. We found profound differences in the factors that influence attention within as well as between the tested species. This study suggests that attention should be incorporated as an important variable when testing species in social situations.
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Punzo, F., & Ludwig, L. (2002). Contact with maternal parent and siblings affects hunting behavior, learning, and central nervous system development in spiderlings of Hogna carolinensis (Araeneae: Lycosidae). Anim. Cogn., 5(2), 63–70.
Abstract: The purpose of this study was to determine the effects of early experience (rearing conditions) on the central nervous system (CNS) and behavior of spiderlings of Hogna carolinensis (Lycosidae). We were interested in whether or not spiderlings that were allowed to remain in contact with their maternal parent and siblings (enriched condition, EC) would exhibit differences in CNS development or subsequent behavior when compared with those reared in isolation (improverished condition, IC). Spiderlings emerged from their egg sacs and climbed onto the dorsal surface of their mother's abdomen where they remained until their yolk supply was depleted (5 days). They dispersed on day 6 after emergence. We compared the ability of 16-day-old EC and IC spiderlings to capture prey in a linear runway and to learn a complex maze (spatial learning). We also compared certain aspects of CNS development (brain weight, total number of brain cells, volume of central body and protocerebral neuropil) in EC and IC spiderlings. Results indicated that EC subjects are more efficient at capturing moving prey (crickets) and exhibited improved performance (significantly fewer blind alley errors) in the maze. The volume of the protocerebral neuropil in 6-day-old EC animals increased 30% over a 5-day period after emergence as compared to IC animals of the same age. The volume of the central body of EC animals increased 34.8% over the same time period. On day 6 after emergence, the weight of the protocerebrum was significantly greater in EC versus IC subjects. There were no significant effects of rearing condition (EC vs IC) or age (1- and 6-day-old spiderlings) on the total number of nerve cells in the protocerebrum, suggesting that the difference in protocerebral weight was due primarily to differences in supporting glial tissues and neuropil matrix. In conclusion, the data suggest that early contact with the maternal parent and siblings is of vital importance to CNS development in lycosid spiderlings and can influence the capacity for spatial learning as well as the ability to capture prey.
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Proops, L., & McComb, K. (2010). Attributing attention: the use of human-given cues by domestic horses (Equus caballus). Anim. Cogn., 13(2), 197–205.
Abstract: Abstract Recent research has shown that domestic dogs are particularly good at determining the focus of human attention, often outperforming chimpanzees and hand-reared wolves. It has been suggested that the close evolutionary relationship between humans and dogs has led to the development of this ability; however, very few other domestic species have been studied. We tested the ability of 36 domestic horses to discriminate between an attentive and inattentive person in determining whom to approach for food. The cues provided were body orientation, head orientation or whether the experimenters’ eyes were open or closed. A fourth, mixed condition was included where the attentive person stood with their body facing away from the subjects but their head turned towards the subject while the inattentive person stood with their body facing the subject but their head turned away. Horses chose the attentive person significantly more often using the body cue, head cue, and eye cue but not the mixed cue. This result suggests that domestic horses are highly sensitive to human attentional cues, including gaze. The possible role of evolutionary and environmental factors in the development of this ability is discussed.
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Proops, L., Burden, F., & Osthaus, B. (2009). Mule cognition: a case of hybrid vigour? Anim. Cogn., 12(1), 75–84.
Abstract: Abstract: This study compares the behaviour of the mule (Equus asinus x Equus caballus) with that of its parent species to assess the effects of hybridization on cognition. Six mules, six ponies (E. caballus) and six donkeys (E. asinus) were given a two choice visual discrimination learning task. Each session consisted of 12 trials and pass level was reached when subjects chose the correct stimulus for at least 9 out of the 12 trials in three consecutive sessions. A record was made of how many pairs each subject learnt over 25 sessions. The mules" performance was significantly better than that of either of the parent species (Kruskal-Wallis: Hx = 8.11, P = 0.017). They were also the only group to learn enough pairs to be able to show a successive reduction in the number of sessions required to reach criterion level. This study provides the first empirical evidence that the improved characteristics of mules may be extended from physical attributes to cognitive function.
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Prato-Previde, E., Marshall-Pescini, S., & Valsecchi, P. (2008). Is your choice my choice` The owners effect on pet dogs? ( Canis lupus familiaris ) performance in a food choice task. Anim. Cogn., 11(1), 167–174.
Abstract: Abstract This study investigates the influence of owners on their dogs performance in a food choice task using either different or equal quantities of food. Fifty-four pet dogs were tested in three different conditions. In Condition 1 we evaluated their ability to choose between a large and small amount of food (quantity discrimination task). In Condition 2 dogs were again presented with a choice between the large and small food quantity, but only after having witnessed their owner favouring the small quantity. In Condition 3 dogs were given a choice between two equally small quantities of food having witnessed their owner favouring either one or the other. A strong effect of the owner on the dogs`` performance was observed. In Condition 1 dogs as a group chose significantly more often the large food quantity, thus showing their ability to solve the quantity discrimination task. After observing their owner expressing a preference for the small food quantity they chose the large quantity of food significantly less than in the independent choice situation. The tendency to conform to the owner`s choice was higher when the dogs had to choose between equally small quantities of food (Condition 3) rather than between a large and a small one (Condition 2). These results provide evidence that dogs can be influenced by their owners even when their indications are clearly in contrast with direct perceptual information, thus leading dogs to ultimately make counterproductive choices.
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Potì, P., Langer, J., Savage-Rumbaugh, S., & Brakke, K. E. (1999). Spontaneous logicomathematical constructions by chimpanzees (Pan troglodytes, P. paniscus). Anim. Cogn., 2(3), 147–156.
Abstract: Two experiments investigated the spontaneous construction of precursory logicomathematical operations by human-enculturated and language-reared chimpanzees (Pan troglodytes, Pan paniscus) when they were interacting freely with objects. In experiment 1, three chimpanzees ranging in age from 6 to 18 years were presented with sets of six objects. Chimpanzees constructed equivalence, order and reversibility relations within single sets of objects as well as between two or three contemporaneous sets of objects. The chimpanzees' logicomathematical operations were more advanced, including infrequent and minimal operations on three sets, than those of some previously investigated younger nonenculturated common chimpanzees. In experiment 2, six chimpanzees ranging in age from 6 to 21 years were presented with sets of 12 objects. Chimpanzees constructed more advanced operations on single sets, but not on contemporaneous sets. The results suggest partial convergence and partial divergence between development of logicomathematical cognition in chimpanzees and humans.
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Potì, P. (2000). Aspects of spatial cognition in capuchins (Cebus apella): frames of reference and scale of space. Anim. Cogn., 3(2), 69–77.
Abstract: Frames of reference (i.e. sets of loci defining spatial locations) determine animals' performances in object search tasks. Reference frames are used at different scales. Although much behavioural research has been conducted on search strategies in many animal species, relatively little has been done on nonhuman primates. The two experiments reported here focused on the relative strength and the level of functioning of different reference frames at the small-scale level in four capuchins (Cebus apella). Two identical boxes and a landmark were placed on a round platform that could be rotated. A reward was hidden in subject's view under one box, and then a sash-screen was lowered to hide the rotation of the platform; the sash-screen was then lifted and the subject allowed to search for the reward. In experiment 1 the rewarded box was always the closer to the landmark, in experiment 2 it could be either the box closer to or the box farther from the landmark. Capuchins were successful after invisible rotations in experiment 1, but they failed after invisible rotations in experiment 2. Two possible explanations are proposed: (1) capuchins relied heavily on the left-right body-axis as a frame, and they could only substitute it with a simple association between the rewarded position and the landmark; or (2) capuchins failed because they chose external cues in the room, therefore on a inappropriate scale. The latter explanation allows two further inferences: (a) the capuchins' choice was indirectly related to their body-axes; and (b) the capuchins revealed a cognitive asymmetry between small-scale and large-scale spaces, thus differing from humans.
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Pongrácz, P., Vida, V., Bánhegyi, P., & Miklósi, Á. (2008). How does dominance rank status affect individual and social learning performance in the dog (Canis familiaris)? Anim. Cogn., 11, 75–82.
Abstract: Dogs can learn effectively to detour around a V-shaped fence after observing a demonstration from either an unfamiliar human or dog demonstrator. We found earlier that there is substantial individual variation between the dogs' performance, even when using the same experimental conditions. Here, we investigate if the subjects' relative dominance rank with other dogs had an effect on their social learning performance. On the basis of the owners' answers to a questionnaire, subjects from multi-dog homes were sorted into groups of dominant and subordinate dogs. In Experiment 1, dominant and subordinate dogs were tested without demonstration and we did not find any difference between the groups-they had similarly low detour performances on their own. In Experiment 2 and 3, dogs from single dog and multi-dog households were tested in the detour task with demonstration by an unfamiliar dog, or human, respectively. The results showed that social learning performance of the single dogs fell between the dominant and subordinate multi-dogs with both dog and human demonstration. Subordinate dogs displayed significantly better performance after having observed a dog demonstrator in comparison to dominant dogs. In contrast, the performance of dominant and subordinate dogs was almost similar, when they observed a human demonstrator. These results suggest that perceived dominance rank in its own group has a strong effect on social learning in dogs, but this effect seems to depend also on the demonstrator species. This finding reveals an intricate organization of the social structure in multi-dog households, which can contribute to individual differences existing among dogs.
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