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Halsey, L. G., Bezerra, B. M., & Souto, A. S. (2006). Can wild common marmosets (Callithrix jacchus) solve the parallel strings task? Anim. Cogn., 9(3), 229–233.
Abstract: Patterned string tasks are a test of perceptual capacity and the understanding of means-end connections. Primates can solve complex forms of this task in laboratories. However, this may not indicate the level of such cognition that is commonly employed in the wild, where decision-making time is often short and distractions such as predator avoidance and competition between conspecifics are often prevalent. The current study tests whether wild common marmosets (Callithrix jacchus) can successfully complete the simplest form of the patterned string task, parallel strings, while in their natural environment. Although 12 out of 13 marmosets could successfully complete the task, in previous laboratory-based studies on primates, the errors at this task by all primate species tested were consistently lower than in the present study. This is probably explained by the added difficulties imposed by the natural setting of the task in the present study, exemplified by a significant increase in observed vigilance behaviour by subject animals prior to attempts at the task that were unsuccessful. The undertaking of such tasks by common marmosets in situ probably provides a more reasonable representation of the levels of cognitive capacity expressed by this species in the wild than do laboratory-based studies of the task.
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Santos, L. R., Pearson, H. M., Spaepen, G. M., Tsao, F., & Hauser, M. D. (2006). Probing the limits of tool competence: experiments with two non-tool-using species (Cercopithecus aethiops and Saguinus oedipus). Anim. Cogn., 9(2), 94–109.
Abstract: Non-human animals vary in their ability to make and use tools. The goal of the present study was to further explore what, if anything, differs between tool-users and non-tool-users, and whether these differences lie in the conceptual or motor domain. We tested two species that typically do not use tools-cotton top tamarins (Saguinus oedipus) and vervet monkeys (Cercopithecus aethiops)-on problems that mirrored those designed for prolific tool users such as chimpanzees. We trained subjects on a task in which they could choose one of two canes to obtain an out-of-reach food reward. After training, subjects received several variations on the original task, each designed to examine a specific conceptual aspect of the pulling problem previously studied in other tool-using species. Both species recognized that effective pulling tools must be made of rigid materials. Subsequent conditions revealed significant species differences, with vervets outperforming tamarins across many conditions. Vervets, but not tamarins, had some recognition of the relationship between a tool's orientation and the position of the food reward, the relationship between a tool's trajectory and the substance that it moves on, and that tools must be connected in order to work properly. These results provide further evidence that tool-use may derive from domain-general, rather than domain-specific cognitive capacities that evolved for tool use per se.
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Lonsdorf, E. V. (2006). What is the role of mothers in the acquisition of termite-fishing behaviors in wild chimpanzees (Pan troglodytes schweinfurthii)? Anim. Cogn., 9(1), 36–46.
Abstract: This paper explores the role of maternal influences on the acquisition of a tool-using task in wild chimpanzees (Pan troglodytes schweinfurthii) in order to build on and complement previous work done in captivity. Young chimpanzees show a long period of offspring dependency on mothers and it is during this period that offspring learn several important skills, especially how to and on what to forage. At Gombe National Park, one skill that is acquired during dependency is termite-fishing, a complex behavior that involves inserting a tool made from the surrounding vegetation into a termite mound and extracting the termites that attack and cling to the tool. All chimpanzees observed at Gombe have acquired the termite-fishing skill by the age of 5.5 years. Since the mother is the primary source of information throughout this time period, I investigated the influence of mothers' individual termite-fishing characteristics on their offsprings' speed of acquisition and proficiency at the skill once acquired. Mother's time spent alone or with maternal family members, which is highly correlated to time spent termite-fishing, was positively correlated to offspring's acquisition of critical elements of the skill. I also investigated the specific types of social interactions that occur between mothers and offspring at the termite mound and found that mothers are highly tolerant to offspring, even when the behavior of the offspring may disrupt the termite-fishing attempt. However, no active facilitation by mothers of offsprings' attempts were observed.
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Virányi, Z., Topál, J., Miklósi, Á., & Csányi, V. (2006). A nonverbal test of knowledge attribution: a comparative study on dogs and children. Anim. Cogn., 9(1), 13–26.
Abstract: The sensitivity of eleven pet dogs and eleven 2.5-year-old children to others' past perceptual access was tested for object-specificity in a playful, nonverbal task in which a human Helper's knowledge state regarding the whereabouts of a hidden toy and a stick (a tool necessary for getting the out-of-reach toy) was systematically manipulated. In the four experimental conditions the Helper either participated or was absent during hiding of the toy and the stick and therefore she knew the place(s) of (1) both the toy and the stick, (2) only the toy, (3) only the stick or (4) neither of them. The subjects observed the hiding processes, but they could not reach the objects, so they had to involve the Helper to retrieve the toy. The dogs were more inclined to signal the place of the toy in each condition and indicated the location of the stick only sporadically. However the children signalled both the location of the toy and that of the stick in those situations when the Helper had similar knowledge regarding the whereabouts of them (i.e. knew or ignored both of them), and in those conditions in which the Helper was ignorant of the whereabouts of only one object the children indicated the place of this object more often than that of the known one. At the same time however, both dogs and children signalled the place of the toy more frequently if the Helper had been absent during toy-hiding compared to those conditions when she had participated in the hiding. Although this behaviour appears to correspond with the Helper's knowledge state, even the subtle distinction made by the children can be interpreted without a casual understanding of knowledge-formation in others.
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Fiset, S., Landry, F., & Ouellette, M. (2006). Egocentric search for disappearing objects in domestic dogs: evidence for a geometric hypothesis of direction. Anim. Cogn., 9(1), 1–12.
Abstract: In several species, the ability to locate a disappearing object is an adaptive component of predatory and social behaviour. In domestic dogs, spatial memory for hidden objects is primarily based on an egocentric frame of reference. We investigated the geometric components of egocentric spatial information used by domestic dogs to locate an object they saw move and disappear. In experiment 1, the distance and the direction between the position of the animal and the hiding location were put in conflict. Results showed that the dogs primarily used the directional information between their own spatial coordinates and the target position. In experiment 2, the accuracy of the dogs in finding a hidden object by using directional information was estimated by manipulating the angular deviation between adjacent hiding locations and the position of the animal. Four angular deviations were tested: 5, 7.5, 10 and 15 degrees . Results showed that the performance of the dogs decreased as a function of the angular deviations but it clearly remained well above chance, revealing that the representation of the dogs for direction is precise. In the discussion, we examine how and why domestic dogs determine the direction in which they saw an object disappear.
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Epstein, R. (1985). Animal cognition as the praxist views it. Neurosci Biobehav Rev, 9(4), 623–630.
Abstract: The distinction between psychology and praxics provides a clear answer to the question of animal cognition. As Griffin and others have noted, the kinds of behavioral phenomena that lead psychologists to speak of cognition in humans are also observed in nonhuman animals, and therefore those who are convinced of the legitimacy of psychology should not hesitate to speak of and to attempt to study animal cognition. The behavior of organisms is also a legitimate subject matter, and praxics, the study of behavior, has led to significant advances in our understanding of the kinds of behaviors that lead psychologists to speak of cognition. Praxics is a biological science; the attempt by students of behavior to appropriate psychology has been misguided. Generativity theory is an example of a formal theory of behavior that has proved useful both in the engineering of intelligent performances in nonhuman animals and in the prediction of intelligent performances in humans.
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Cattell, R. B., & Korth, B. (1973). The isolation of temperament dimensions in dogs. Behav Biol, 9(1), 15–30.
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Clement, T. S., & Zentall, T. R. (2003). Choice based on exclusion in pigeons. Psychon Bull Rev, 10(4), 959–964.
Abstract: When humans acquire a conditional discrimination and are given a novel-sample-comparison choice, they often reject a comparison known to be associated with a different sample and choose the alternative comparison by default (or by exclusion). In Experiment 1, we found that if, following matching training, we replaced both of the samples, acquisition took five times longer than if we replaced only one of the samples. Apparently, the opportunity to reject one of the comparisons facilitated the association of the other sample with the remaining comparison. In Experiment 2, we first trained pigeons to treat two samples differently (to associate Sample A with Comparison 1 and Sample B with Comparison 2) and then trained them to associate one of those samples with a new comparison (e.g., Sample A with Comparison 3) and to associate a novel sample (Sample C) with a different, new comparison (Comparison 4). When Sample B then replaced Sample C, the pigeons showed a significant tendency to choose Comparison 4 over Comparison 3. Thus, when given the opportunity, pigeons will choose by exclusion.
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Bouchard, J., Goodyer, W., & Lefebvre, L. (2007). Social learning and innovation are positively correlated in pigeons (Columba livia). Anim. Cogn., 10(2), 259–266.
Abstract: When animals show both frequent innovation and fast social learning, new behaviours can spread more rapidly through populations and potentially increase rates of natural selection and speciation, as proposed by A.C. Wilson in his behavioural drive hypothesis. Comparative work on primates suggests that more innovative species also show more social learning. In this study, we look at intra-specific variation in innovation and social learning in captive wild-caught pigeons. Performances on an innovative problem-solving task and a social learning task are positively correlated in 42 individuals. The correlation remains significant when the effects of neophobia on the two abilities are removed. Neither sex nor dominance rank are associated with performance on the two tasks. Free-flying flocks of urban pigeons are able to solve the innovative food-finding problem used on captive birds, demonstrating it is within the range of their natural capacities. Taken together with the comparative literature, the positive correlation between innovation and social learning suggests that the two abilities are not traded-off.
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Bard, K. A. (2007). Neonatal imitation in chimpanzees (Pan troglodytes) tested with two paradigms. Anim. Cogn., 10(2), 233–242.
Abstract: Primate species differ in their imitative performance, perhaps reflecting differences in imitative capacity. The developmentally earliest form of imitation in humans, neonatal imitation, occurs in early interactions with social partners, and may be a more accurate index of innate capacity than imitation of actions on objects, which requires more cognitive ability. This study assessed imitative capacity in five neonatal chimpanzees, within a narrow age range (7-15 days of age), by testing responses to facial and vocal actions with two different test paradigms (structured and communicative). Imitation of mouth opening was found in both paradigms. In the communicative paradigm, significant agreement was found between infant actions and demonstrations. Additionally, chimpanzees matched the sequence of three actions of the TC model, but only on the second demonstration. Newborn chimpanzees matched more modeled actions in the communicative test than in the structured paradigm. These performances of chimpanzees, at birth, are in agreement with the literature, supporting a conclusion that imitative capacity is not unique to the human species. Developmental histories must be more fully considered in the cross-species study of imitation, as there is a greater degree of innate imitative capacity than previously known. Socialization practices interact with innate and developing competencies to determine the outcome of imitation tests later in life.
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