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Timney, B., & Keil, K. (1999). Local and global stereopsis in the horse. Vision Res, 39(10), 1861–1867.
Abstract: Although horses have laterally-placed eyes, there is substantial binocular overlap, allowing for the possibility that these animals have stereopsis. In the first experiment of the present study we measured local stereopsis by obtaining monocular and binocular depth thresholds for renal depth stimuli. On all measures, the horses' binocular performance was superior to their monocular. When depth thresholds were obtained, binocular thresholds were several times superior to those obtained monocularly, suggesting that the animals could use stereoscopic information when it was available. The binocular thresholds averaged about 15 min arc. In the second experiment we obtained evidence for the presence of global stereopsis by testing the animals' ability to discriminate between random-dot stereograms with and without consistent disparity information. When presented with such stimuli they showed a strong preference for the cyclopean equivalent of the positive stimulus with the real depth. These results provide the first behavioral demonstration of a full range of stereoscopic skills in a lateral-eyed mammal.
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Tomasello, M. (1999). The cultural origins of human cognition. Camebridge,MA.: Harvard University Press.
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Tomasello, M., Hare, B., & Agnetta, B. (1999). Chimpanzees, Pan troglodytes, follow gaze direction geometrically. Anim. Behav., 58(4), 769–777.
Abstract: Two experiments on chimpanzee gaze following are reported. In the first, chimpanzee subjects watched as a human experimenter looked around various types of barriers. The subjects looked around each of the barriers more when the human had done so than in a control condition (in which the human looked in another direction). In the second experiment, chimpanzees watched as a human looked towards the back of their cage. As they turned to follow the human's gaze a distractor object was presented. The chimpanzees looked at the distractor while still following the human's gaze to the back of the cage. These two experiments effectively disconfirm the low-level model of chimpanzee gaze following in which it is claimed that upon seeing another animate being's gaze direction chimpanzees simply turn in that direction and look around for something interesting. Rather, they support the hypothesis that chimpanzees follow the gaze direction of other animate beings geometrically to specific locations, in much the same way as human infants. The degree to which chimpanzees have a mentalistic interpretation of the gaze and/or visual experience of others is still an open question.
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Topál, J., & Csányi, V. (1999). Interactive learning in the paradise fish (Macropodus opercularis): an ethological interpretation of the second-order conditioning paradigm. Anim. Cogn., 2(4), 197–206.
Abstract: This study was aimed at the examination of 'mental construction' in paradise fish by interactive learning, which is suggested as an alternative hypothesis for backward or second-order conditioning. Avoidance of goldfish was established in paradise fish by presenting a harmless goldfish (a novel stimulus) after an aversive event (mild electric shocks) in the dark compartment of a shuttle tank. It was found that this avoidance depended on context pre-exposure. Experiment 1 was designed to study the effect of mild shocks on shuttling activity in a familiar context. Experiment 2 aimed at establishing fear-conditioning to the goldfish in a higher-order conditioning paradigm. In the course of training, unpaired stimuli were presented in the dark compartment of the shuttle tank in such a manner that the presentation of mild shocks (20 mA) preceded the encounter with a harmless fish (goldfish). Experiment 3 demonstrated the role of context pre-exposure in interactive learning. Results indicate that (1) while 60 mA shocks resulted in avoidance of the dark compartment, the 20 mA mild shocks affected exploratory behaviour; (2) after pre-exposure to the training environment, paradise fish avoided the dark compartment containing goldfish provided that subjects had previously encountered mild, explorative shocks there; (3) this conditioned fear, a 'mental construction' of a potential danger, was proved to be transferable to another context and was consequently aimed specifically at the goldfish, a living being, rather than the training context; (4) the pre-exposure to the shuttle tank was an important part of this training procedure, that is, only subjects habituated to the shuttle tank avoided the goldfish. Results are discussed in the framework of the Interactive Learning Hypothesis, which has been developed as an ethological approach to a higher-order conditioning paradigm.
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Treichler, F. R., & Van Tilburg, D. (1999). Training requirements and retention characteristics of serial list organization by macaque monkeys. Anim. Cogn., 2(4), 235–244.
Abstract: This work evaluated the prospect that organizational accounts of the retention of list information by monkeys might be an artifact of familiarity with conditional relationships. Seven sophisticated macaques were trained on four five-item lists. Each acquisition selectively excluded one of the internal conditional pairs of the typical four-problem sequence (AB,BC,CD,DE) that defines a five-item serially ordered list. Then, all possible novel pairings and the trained pairs appeared together in a test. After this, the previously omitted pair was trained and animals were retested. On all tasks, initial tests revealed little organization and much intersubject variability of characteristic choice strategies, but subsequent inclusion of all four conditional pairs always yielded organized serial choice. On both the four-problem tests and in a later retention, errors were directly related to interitem distance between the objects paired on test trials. These results helped to specify the conditions required for demonstration of non-human primate analogs of transitivity, and showed that even sophisticated monkeys organize information in retention only if they know all interitem relationships.
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Tschudin, A. (1999). Relative Neocortex Size and Its Correlates in Dolphins: Comparisons with Humans and Implications for Mental Evolution. Ph.D. thesis, University of Natal, Pietermaritzburg, South Africa.
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Vallortigara G., Regolin L., & Pagni P. (1999). Detour behaviour, imprinting and visual lateralization in the domestic chick. Cognitive Brain Research, 7, 307–320.
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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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Walker, E. P., & Nowak, R. M. (1999). Walker's Mammals of the World.
Abstract: Description
From reviews of previous editions: “Professional naturalists will find [these volumes] invaluable as a handy reference, and amateurs at least those citizens alive to their earthly environment should delight in finding so much fascinating information made so available and palatable. Audubon ”What an amazing lot mammals are, seen here in all of their diversity! . . . Walker has made available a mine of information, for the specialist as well as for the casually interested . . . If you want to find out about a mammal, then, here is the place to look.“New York Times ”Every mammalogist must have [these books], and those who profess a broad interest in the fauna of the world will want them.“Natural History From aardwolves and bandicoots to yapoks and zorillas, Ernest P. Walker's Mammals of the World is the most comprehensive the pre-eminent reference work on mammals. Now, completely revised and updated, this fascinating guide is better than ever. Providing a complete account of every genus of mammal in all historical time, the sixth edition is 25 percent longer than its predecessor. Of the previous generic accounts, 95 percent have been substantively modified, and there are 80 new ones among them, three remarkable, large ungulates recently discovered in the forests of Indochina. New also is a full account of the woolly mammoth, now known to have survived until less than 4,000 years ago. Each section of the book describes one genus and includes facts such as scientific and common names, the number and distribution of species, measurements and physical traits, habitat, locomotion, daily and seasonal activity, population dynamics, home range, social life, reproduction, and longevity. Textual summaries present accurate, well-documented descriptions of the physical characteristics and living habits of mammals in every part of the world. As in the last two editions, the names and distributions of every species of every genus are listed in systematic order. These lists have now been cross-checked to ensure coverage of all species in the comprehensive new Smithsonian guide, Mammal Species of the World. Facts on the biology of mammals have been brought together from more than 2,700 newly cited references, nearly all published in the last decade. Also new are the latest data on reproduction, longevity, fur harvests, numbers in the wild and in captivity, and conservation status. The sixth edition also records all official classifications of every mammal species and subspecies in the massive 1996 IUCN Red List of Threatened Animals. The illustrations more than 1,700 include virtually every genus of mammal. Among them are pictures by such noted wildlife photographers as Leonard Lee Rue III, Bernhard Grzimek, David Pye, and Warren T. Houck. Mammals pictured here for the first time include the just-discovered giant muntjac deer of Viet Nam, a rodent known only from the Solomon Islands, a large fruit bat whose male suckles the young, and an extremely rare web-footed tenrec of Madagascar. Since its publication in 1964, Walker's Mammals of the World has become a favorite guide to the natural world for general readers as well as an invaluable resource for professionals. This sixth edition represents more than half a century of scholarship? Ernest P. Walker himself devoted more than thirty years to the original project and remains true to Walker's vision, smoothly combining thorough scholarship with a popular, readable style to preserve and enhance what the Washington Post called ”a landmark of zoological literature." Reviews “"An absolute treasure trove--a 'must' for the working naturalist as well as for any person who has curiosity about the world's mammals.”Roger Tory Peterson."? “Unlike many academic reference works, all editions [Walker's Mammals], the new one included, are as accessible to amateurs as to professionals . . . For wildlife enthusiasts, this two-volume set is an indispensable resource. The new edition not only updates taxonomic information generated in the last 10 years, it pushes back the historical record, including all mammals known to have existed in the past 5,000 years. Twenty-one new genera also appear, animals that have recently been discovered. Either volume is hefty enough to kill a small mammal if dropped there's a total of 2,160 pages . . . And despite almost a decade between editions the last edition appeared in 1991 the price has remained virtually the same, despite an increase in book size of more than 20 percent. After being exposed to this kind of thorough, detailed information saturation, many readers may find it hard to go back to a plain old encyclopedia for their animal questions.”Bloomsbury Review “For anyone who needs an up-to-date, comprehensive guide to every known species of mammal, Walker's Mammals of the World is an essential purchase.”Nicholas Gould, International Zoo News “A massive compilation ideal for readers who want to have at their fingertips information on every mammal species.”International Zoo News Author Information Ernest P. Walker (1891-1969) began work on Mammals of the World in the early 1930s, when he became assistant director of the National Zoo in Washington. His work reflected an unequaled store of knowledge about the world's mammals. Ronald M. Nowak was senior author of the fourth edition and author of the fifth edition of Walker's Mammals of the World. His other works on mammalogy include North American Quaternary Canis and several parts of the National Geographic Society's Wild Animals of North America, for which he also was editorial consultant. He received a Ph.D. in biology from the University of Kansas in 1973 and was staff mammalogist at the former Office of Endangered Species, U.S. Fish and Wildlife Service, from 1974 to 1987. He served as an Air Force officer for four years and is a private pilot. |
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Wauters, A. M., Richard-Yris, M. - A., Richard, J. P., & Foraste M. (1999). Internal and external factors modulate food-calling in domestic hens. Anim. Cogn., 2(1), 1–10.
Abstract: Two series of experiments investigated factors affecting utterance of food calls in the domestic hen, Gallus domesticus. The first series of experiments tested the effect of food preference and the hen’s internal state on the utterance of food calls. Different food types were presented first singly and then in a choice test to 20 hens, first when hens were laying, and then when they were maternal. The second series of experiments tested the effect of hunger level on the utterance of food calls in laying hens, and maternal hens with or without chicks. These two series of experiments showed that laying hens and maternal hens showed a similar marked preference for certain types of food, but laying hens very rarely emitted food calls, in contrast to maternal hens. This shows the effect of the bird’s psychophysiological state on her tendency to emit food calls. The more a maternal hen preferred a food type, the more food calls she emitted. This was observed from the beginning of a test in single-food tests as well as in choice tests. Hunger level positively affected food-call production under certain feeding conditions in maternal hens, but not in laying hens. When maternal hens were tested in the absence of their chicks, utterance of food calls was more sustained than in the presence of chicks.
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