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Santi, A., Stanford, L., & Symons, J. (1998). An analysis of confusion errors in many-to-one matching with temporal and nontemporal samples. Anim. Cogn., 1(1), 37–46.
Abstract: In experiment 1, pigeons were trained to match temporal (2, 8, and 10 s of houselight) and location (feeder light, left key, center key illumination) samples to color comparison stimuli. Red choices were correct following the 2-s and feeder light, orange choices were correct following the 8-s and center key, and green choices were correct following the 10-s and left key. Samples that were harder to discriminate (8- vs 10-s, and left vs center key) were mapped onto comparisons that were easy to discriminate (orange vs green), while samples that were easier to discriminate (2- vs 8-s, and feeder light vs left key) were mapped onto comparisons that were hard to discriminate(red vs orange). The pattern of errors for temporal and location samples indicated that these samples were not represented by a common code even though they were associated with the same comparison stimuli. In experiment 2, the same pigeons were trained with visual samples in which samples that were hard to discriminate (triangle vs circle) were mapped onto comparisons that were easy to discriminate (orange vs green), while samples that were easy to discriminate(plus vs triangle) were mapped onto comparisons that were hard to discriminate (red vs orange). Following acquisition of the visual discrimination, the temporal samples were re-introduced and many-to-one training was continued. During delay testing, the pattern of errors for temporal and visual samples was equivalent and consistent with the hypothesis that visual samples were being coded in terms of the duration appropriate for the temporal sample with which it shared a common comparison response. Data from no-sample test sessions ruled out a simple response bias explanation of the data. The properties of common codes for temporal and nontemporal events can be somewhat flexible and more complicated than previously envisaged.
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Fagot, J., Kruschke, J. K., Dépy, D., & Vauclair, J. (1998). Associative learning in baboons (Papio papio) and humans (Homo sapiens): species differences in learned attention to visual features. Anim. Cogn., 1(2), 123–133.
Abstract: We examined attention shifting in baboons and humans during the learning of visual categories. Within a conditional matching-to-sample task, participants of the two species sequentially learned two two-feature categories which shared a common feature. Results showed that humans encoded both features of the initially learned category, but predominantly only the distinctive feature of the subsequently learned category. Although baboons initially encoded both features of the first category, they ultimately retained only the distinctive features of each category. Empirical data from the two species were analyzed with the 1996 ADIT connectionist model of Kruschke. ADIT fits the baboon data when the attentional shift rate is zero, and the human data when the attentional shift rate is not zero. These empirical and modeling results suggest species differences in learned attention to visual features.
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Benhamou, S. (1998). Place navigation in mammals: a configuration-based model. Anim. Cogn., 1(1), 55–63.
Abstract: Recent water maze experiments suggest that rats performing place navigation primarily use the geometric information provided by a set of landmarks, and neglect the featural information provided by the identities of the landmarks. Here, I develop a model that explains how an animal may perform place navigation by relying only on geometric information. The core of the model is the representation of places as panoramas defined by circular bar-codes embodying the relative bearings and apparent sizes of the landmarks, irrespective of their identities. There are two stages in the model. During the first stage, the animal freely explores its environment in order to acquire spatial information at the local level. During the second stage, the animal uses the information previously memorized to perform place navigation towards the goal it intends to reach. The possible role of two brain areas in place navigation is discussed within this framework. Beyond their primary role in landmark-based representations of places, hippocampal place cells may be involved in computing the current distances to the landmarks. Beyond their primary role in landmark-based representations of headings, post-subicular head-direction cells may be involved in computing the “compass bearings” of the landmarks.
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Vallortigara, G., Regolin, L., Rigoni, M., & Zanforlin, M. (1998). Delayed search for a concealed imprinted object in the domestic chick. Anim. Cogn., 1(1), 17–24.
Abstract: Five-day-old chicks were accustomed to follow an imprinted object (a small red ball with which they had been reared) that was moving slowly in a large arena, until it disappeared behind an opaque screen. In experiments, each chick was initially confined in a transparent cage, from where it could see and track the ball while it moved towards, and then beyond, one of two screens. The screens could be either identical or differ in colour and pattern. Either immediately after the disappearance of the ball, or with a certain delay, the chick was released and allowed to search for its imprinted object behind either screen. The results showed that chicks took into account the directional cue provided by the ball movement and its concealment, up to a delay period of about 180 s, independently of the perceptual characteristics of the two screens. If an opaque partition was positioned in front of the transparent cage immediately after the ball had disappeared, so that, throughout the delay, neither the goal-object nor the two screens were visible, chicks were still capable of remembering and choosing the correct screen, though over a much shorter period of about 60 s. The results suggest that, at least in this precocial bird species, very young chicks can maintain some form of representation of the location where a social partner was last seen, and are also capable of continuously updating this representation so as to take into account successive displacements of the goal-object.
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Shuster, G., & Sherman, P. W. (1998). Tool use by naked mole-rats. Anim. Cogn., 1(1), 71–74.
Abstract: Naked mole-rats (Heterocephalus glaber, Rodentia: Bathyergidae) excavate extensive subterranean burrows with their procumbent incisors. Captive individuals often place a wood shaving or tuber husk behind their incisor teeth and in front of their lips and molar teeth while gnawing on substrates that yield fine particulate debris. This oral barrier may prevent choking or aspiration of foreign material. Consistent use of tools has rarely been reported in rodents.
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McNelis, N. L., & Boatright-Horowitz, S. L. (1998). Social monitoring in a primate group: the relationship between visual attention and hierarchical ranks. Anim. Cogn., 1(1), 65–69.
Abstract: Social monitoring has been hypothesized to be an important component of primate social behavior. If the gaze direction of one animal can redirect the gaze of another, visual scanning of conspecifics can provide a more efficient means of locating food or predators than directly scanning the entire nonsocial environment. Social monitoring also allows distance regulation between members of a group, reducing the likelihood of agonistic encounters. Although assessment of gaze direction in freely moving primates is problematic, we were successful in assessing amounts of visual scanning among adult females of a captive, socially housed group of patas monkeys (Erythrocebus patas) using a focal sampling technique with on-the-dot recording (5-s sampling intervals). In study 1, relative amounts of scanning were assessed as subjects gazed at any other member of the group. Percentages of agreement between observers ranged from 80% to 92%, with corresponding s values ranging from 0.74 to 0.92. In study 2, relative amounts of visual scanning were assessed so that specific targets of gaze were identified. The resultant data supported a long-standing prediction about the role of social monitoring in primate group dynamics. Lower-ranking animals gazed toward higher-ranking animals more often than vice versa. Although the specific cues eliciting social monitoring remain to be determined, visual attention in this social primate group appeared to be systematically related to hierarchical ranks, assessed by displacements. Minimally, these results suggest that patas monkeys structure their visual attention based on previous encounters with other members of their social group. While simple discrimination learning could account for these results, the demonstration of a systematic relationship between visual attention and primate social dynamics is relevant to current discussions of a primate's understanding of conspecific gaze direction.
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Miklósi, A., Polgárdi, R., Topál, J., & Csányi, V. (1998). Use of experimenter-given cues in dogs. Anim. Cogn., 1(2), 113–121.
Abstract: Since the observations of O. Pfungst the use of human-provided cues by animals has been well-known in the behavioural sciences (“Clever Hans effect”). It has recently been shown that rhesus monkeys (Macaca mulatta) are unable to use the direction of gazing by the experimenter as a cue for finding food, although after some training they learned to respond to pointing by hand. Direction of gaze is used by chimpanzees, however. Dogs (Canis familiaris) are believed to be sensitive to human gestural communication but their ability has never been formally tested. In three experiments we examined whether dogs can respond to cues given by humans. We found that dogs are able to utilize pointing, bowing, nodding, head-turning and glancing gestures of humans as cues for finding hidden food. Dogs were also able to generalize from one person (owner) to another familiar person (experimenter) in using the same gestures as cues. Baseline trials were run to test the possibility that odour cues alone could be responsible for the dogs' performance. During training individual performance showed limited variability, probably because some dogs already “knew” some of the cues from their earlier experiences with humans. We suggest that the phenomenon of dogs responding to cues given by humans is better analysed as a case of interspecific communication than in terms of discrimination learning.
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Pavey, C. R., & Smyth, A. K. (1998). Effects of avian mobbing on roost use and diet of powerful owls,Ninox strenua. Anim. Behav., 55(2), 313–318.
Abstract: We observed the species and numbers of mobbing birds and their effects on a large, nocturnal, bird-eating predator, the powerful owl, together with the pattern of owl predation on mobbing and non-mobbing species. Owls were mobbed on 35 occasions by seven of 44 species of forest birds at a site composed of open forest (88% by area) and rainforest (12%). The majority of bouts involved individuals of a single species, although mixed groups were observed on nine occasions. Regular mobbers were between 4 and 26% of the owls' body weight. Owls abandoned their daytime roosts during 20% of bouts and responded by calling or actively monitoring mobbers during 54% of bouts. Mobbing appeared to explain why owls roosted in rainforest significantly more often than expected by its availability, mobbing being significantly less frequent in rainforest than in open forest. Only one mobbing species regularly occupied rainforest and the canopy of roosts in rainforest was denser than that in open forest, thus reducing the chances of an owl being detected by potential mobbers. Twelve species of forest birds were within the range of prey size of the powerful owl (75-800 g): six were mobbers and six non-mobbers. The frequency of owl predation on non-mobbers was 8.75 times that on mobbers. The species in this study took a high risk by mobbing a very large predator, but benefited by greatly reducing their chances of predation.
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Kamil, A. C. (1998). On the Proper Definition of Cognitive Ethology. In Russell P. Balda, Irene M. Pepperberg, & Alan C. Kamil (Eds.), Animal Cognition in Nature (pp. 1–28). London: Academic Press.
Abstract: Summary The last 20-30 years have seen two `scientific revolutions' in the study of animal behavior: the cognitive revolution that originated in psychology, and the Darwinian, behavioral ecology revolution that originated in biology. Among psychologists, the cognitive revolution has had enormous impact. Similarly, among biologists, the Darwinian revolution has had enormous impact. The major theme of this chapter is that these two scientific research programs need to be combined into a single approach, simultaneously cognitive and Darwinian, and that this single approach is most appropriately called cognitive ethology.
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Piggins, D., & Phillips, C. J. C. (1998). Awareness in domesticated animals--concepts and definitions. Appl. Anim. Behav. Sci., 57(3-4), 181–200.
Abstract: Humans will probably never experience the awareness of another species, but adopting a broad concept of awareness leads to the conclusion that other species have some awareness. The existence of a more complex mind in humans, compared with other species, leads some to suggest that awareness only exists in humans. We postulate that humans possess a significantly increased level of awareness, facilitated in particular by the acquisition of language, but that generally animals possess a level of awareness that is appropriate to their needs. Categories of awareness can be devised by identifying levels, such as are used in the identification of the conscious state in humans, or by ranking states of awareness in order of complexity. A scheme is proposed that combines these two approaches, which is considered suitable for use with domesticated animals. The advantages of identifying awareness as being sensation-, perception- or cognition-based are discussed, as well as the possibility of a scheme based on the degree and site of CNS processing. Finally, the acquisition of awareness by learning and inheritance is considered, and it is argued that in variable environments, animals will evolve increased awareness, whereas in very stable environments the energetic cost of awareness will encourage the evolution of less aware animals.
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