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Templeton, J. J., Kamil, A. C., & Balda, R. P. (1999). Sociality and social learning in two species of corvids: The pinyon jay (Gymnorhinus cyanocephalus) and the Clark's nutcracker (Nucifraga columbiana). J. Comp. Psychol., 113(4), 450–455.
Abstract: The hypothesis that social learning is an adaptive specialization for social living predicts that social species should learn better socially than they do individually, but that nonsocial species should not exhibit a similar enhancement of performance under social learning conditions. The authors compared individual and social learning abilities in 2 corvid species: the highly social pinyon jay (Gymnorhinus cyanocephalus) and the less social Clark's nutcracker (Nucifraga columbiana). The birds were tested on 2 different tasks under individual and social learning conditions. Half learned a motor task individually and a discrimination task socially; the other half learned the motor task socially and the discrimination task individually. Pinyon jays learned faster socially than they did individually, but nutcrackers performed equally well under both learning conditions. Results support the hypothesis that social learning is an adaptive specialization for social living in pinyon jays. (PsycINFO Database Record (c) 2007 APA, all rights reserved)
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Vervaecke, H., Vries, H. D., & Elsacker, L. V. (1999). An Experimental Evaluation Of The Consistency Of Competitive Ability And Agonistic Dominance In Different Social Contexts In Captive Bonobos. Behaviour, 136(4), 423–442.
Abstract: Bonobos have been described as a relatively egalitarian and female dominant species. The exact nature and quality of their dominance relationships and the existence of female dominance are current topics of dispute. We investigated the consistency across social contexts, the stability in time, and the degree of expression of the competitive feeding ability and agonistic dominance in a captive group of bonobos. First, we examined whether the competitive feeding ranks and agonistic ranks differed in different dyadic contexts, triadic contexts and the whole group context. For some pairs of animals the dominance relationships with respect to competitive feeding altered with different group compositions. The agonistic dominance relationships changed accordingly. The competitive feeding ranks and agonistic ranks in the experiments correlated strongly with each other. The alpha position was occupied by a female, but not all females outranked all males. We suggest that females can profit from each others presence to gain inter-sexual dominance. Second, although the agonistic rank order in the whole group remained the same over at least five years, some dyadic competitive feeding ranks changed over time, resulting in a stronger female intersexual dominance. Third, the degree of expression of the behaviors used to quantify dyadic competitive and agonistic dominance was not high, in line with the popular 'egalitarian' epithet. Notwithstanding its low consistency across contexts, the dominance hierarchy in the whole group has a strong predictive value for other social relationships such as grooming. Given this strong effect of rank on other behaviours and given the strong dependency of rank on social context, the choice of the right party members may be a crucial factor in the fission-fusion processes of free-ranging bonobos.
Keywords: BONOBO PAN PANISCUS; RANK ORDERS; FEEDING SCORES; AGONISTIC RANKS; PEERING
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Berger, A., Scheibe, K. - M., Eichhorn, K., Scheibe, A., & Streich, J. (1999). Diurnal and ultradian rhythms of behaviour in a mare group of Przewalski horse (Equus ferus przewalskii), measured through one year under semi-reserve conditions. Appl. Anim. Behav. Sci., 64(1), 1–17.
Abstract: Investigations were conducted on four horses from a group of 12 Przewalski mares raised in different zoos and kept in a 44-ha enclosure under semi-natural conditions. Activity and feeding were continuously measured every second and were saved every 15 min by the storage-telemetry system ETHOSYS, from June 1995 to July 1996. Body mass of the horses was regularly recorded. Daily and monthly mean values, power spectra and DFC (as a measure for stability of rhythms synchronised with circadiurnal period) for activity and feeding were calculated. The general pattern of activity and feeding over the year was closely related to sunrise and sunset. Feeding accounted for 40% of total activity in summer and 62% in spring (all-year average being 52%). The level of activity was lowest in winter; whereas feeding was lowest in summer. The time budget for feeding reflected both feeding conditions and the annual pattern of body condition. Greatest activity occurred during daylight hours. Only on hot summer days, activity at night was higher than during daylight hours. Spectral analysis of activity and feeding in Przewalski horse showed a time pattern which was characterised by 24-h rhythmicity, but also by ultradian components with period lengths between 4.8 and 12 h, i.e., an activity pattern of up to five strong bouts per day. Annual variation in the pattern of power spectra was not high during the year. Results are discussed in connection with horse feeding strategy. Analysing the time structure of long-term and continuously measured activity and feeding could be a useful method to follow the general living conditions, especially the nutritional situation and to detect stressful conditions.
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Kolter, L., Schach, C., & Weber, T. (1999). Habitat use of feral and Przewalski's horses. Natur- und Kulturlandschaft, 3(332-342).
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Silk, J. B. (1999). Male bonnet macaques use information about third-party rank relationships to recruit allies. Anim. Behav., 58(1), 45–51.
Abstract: Social challenges may have driven the evolution of intelligence in primates and other taxa. In primates, the social intelligence hypothesis is supported by evidence that primates know a lot about their own relationships to others and also know something about the nature of relationships among other individuals (third-party relationships). Knowledge of third-party relationships is likely to play an especially important role in coalitions, which occur when one individual intervenes in an ongoing dispute involving other group members, by helping individuals to predict who will support or intervene against them when they are fighting with particular opponents, and to assess which potential allies are likely to be effective in coalitions against their opponents. To date, however, there is no evidence that primates make use of knowledge of third-party relationships when they form coalitions. Here, I show that male bonnet macaques, Macaca radiata , use information about third-party rank relationships when they recruit support from other males. Males consistently chose allies that outranked themselves and their opponents, and made such choices considerably more often than would be expected by chance alone. The analysis shows that the data do not fit simpler explanations based upon males' knowledge of their own relationships to other males or males' ability to recognize powerful allies.
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Boysen, S. T., & Himes, G. T. (1999). Current Issues And Emerging Theories In Animal Cognition. Annual Review of Psychology, 50(1), 683–705.
Abstract: Comparative cognition is an emerging interdisciplinary field with contributions from comparative psychology, cognitive/experimental and developmental psychology, animal learning, and ethology, and is poised to move toward greater understanding of animal and human information-processing, reasoning, memory, and the phylogenetic emergence of mind. This chapter highlights some current issues and discusses four areas within comparative cognition that are yielding new approaches and hypotheses for studying basic conceptual capacities in nonhuman species. These include studies of imitation, tool use, mirror self-recognition, and the potential for attribution of mental states by nonhuman animals. Though a very old question in psychology, the study of imitation continues to provide new avenues for examining the complex relationships among and between the levels of imitative behaviors exhibited by many species. Similarly, recent work in animal tool use, mirror self-recognition (with all its contentious issues), and recent attempts to empirically study the potential for attributional capacities in nonhumans, all continue to provide fresh insights and novel paradigms for addressing the defining characteristics of these complex phenomena.
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López, J. C., Broglio, C., Rodríguez, F., Thinus-Blanc, C., & Salas, C. (1999). Multiple spatial learning strategies in goldfish (Carassius auratus). Anim. Cogn., 2(2), 109–120.
Abstract: There is a considerable amount of evidence that mammals and birds can use different spatial learning strategies based on multiple learning and memory systems. Unfortunately, only a few studies have investigated spatial learning and memory mechanisms in other vertebrates. This study aimed to identify the strategies used by goldfish to solve two different spatial tasks in a series of three experiments. In experiment 1, two groups of goldfish (Carassius auratus) were trained either in a spatial constancy task (SC), in which visual cues signalled the goal indirectly, or in a directly cued task (DC) in which similar cues signalled the goal directly. Transfer tests were conducted to study the effects of discrete cue deletion on the performance in both tasks. In these transfer tests the performance of the animals trained in the DC task dropped to chance level when the cue that signalled the goal directly was removed. In contrast, the removal of any single cue did not disrupt SC performance. In experiment 2, fish trained in the SC or the DC task were trained with the goal reversed. Goldfish in the SC group needed fewer sessions to master the reversal task than DC animals. Finally, experiment 3 investigated the effects of a substantial modification of the geometrical features of the apparatus on the performance of animals trained in the SC or in the DC condition. The performance of DC goldfish was not affected, whereas the same change disrupted performance in the SC animals despite the presence of the visual cues. These results suggest that there are separate spatial learning and memory systems in fish. Whereas the DC animals used a typical guidance strategy, relying only on the cue that signalled the goal directly, SC fish relied on a strategy with the properties of an actual spatial mapping system. Thus, the comparative approach points to the generality of these learning strategies among vertebrates.
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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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Fountain, S. B., Rowan, J. D., & Benson, D. M. J. (1999). Rule learning in rats: serial tracking in interleaved patterns. Anim. Cogn., 2(1), 41–54.
Abstract: Humans have the ability to chunk together information from nonadjacent serial positions in sequential patterns. For example, human subjects can extrapolate the pattern, A-M-B-N-C-O-D-P-E-..., to find the missing element, Q, by sorting pattern elements into two component interleaved subpatterns: A-B-C-D-E and M-N-O-P-... Two experiments investigated the ability of rats to reorganize pattern elements from nonadjacent serial positions into chunks not presented by the experimenter. Rats learned either a structured or unstructured sequence interleaved with elements of a repeating sequence (experiment 1) or an alternation sequence (experiment 2). In both experiments, rats learned the interleaved subpatterns at different rates. Acquisition rate was correlated with the structural properties of component subpatterns and the nature of the rules required to describe the interleaved subpatterns. The results indicate that rats are sensitive to the organization of nonadjacent elements in serial patterns and that they can detect and sort structural relationships in interleaved patterns.
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Cook, R. G., & Tauro, T. L. (1999). Object-goal positioning influences spatial representation in rats. Anim. Cogn., 2(1), 55–62.
Abstract: Three tests investigated how the geometric relation between object/landmarks and goals influenced spatial choice behavior in rats. Two groups searched for hidden food in an object-filled circular arena containing 24 small poles. For the “Proximal” group, four distinct objects in a square configuration were placed close to four baited poles. For the “Distal” group, the identical configuration of objects was rotated 45° relative to the poles containing the hidden food. The Proximal group learned to locate the baited poles more quickly than the Distal group. Tests with removed and rearranged landmarks indicated that the two groups learned to use the objects differently. The results suggested that close proximity of objects to goals encouraged their use as beacons, while greater distance of objects from goals resulted in the global encoding of the geometric properties of the arena and the use of the objects as landmarks.
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