| Records |
| Author |
Pepperberg, I.M.; Brezinsky, M.V. |
| Title |
Acquisition of a relative class concept by an African gray parrot (Psittacus erithacus): discriminations based on relative size |
Type |
Journal Article |
| Year |
1991 |
Publication |
Journal of Comparative Psychology |
Abbreviated Journal |
J Comp Psychol |
| Volume |
105 |
Issue |
3 |
Pages |
286-294 |
| Keywords |
Animals; Aptitude; *Concept Formation; *Discrimination Learning; Form Perception; Male; Mental Recall; *Parrots; *Size Perception; Vocalization, Animal |
Abstract  |
We report that an African gray parrot (Psittacus erithacus), Alex, responds to stimuli on a relative basis. Previous laboratory studies with artificial stimuli (such as pure tones) suggest that birds make relational responses as a secondary strategy, only after they have acquired information about the absolute values of the stimuli. Alex, however, after learning to respond to a small set of exemplars on the basis of relative size, transferred this behavior to novel situations that did not provide specific information about the absolute values of the stimuli. He responded to vocal questions about which was the larger or smaller exemplar by vocally labeling its color or material, and he responded “none” if the exemplars did not differ in size. His overall accuracy was 78.7%. |
| Address |
Northwestern University |
| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Washington, D.C. : 1983 |
Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0735-7036 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:1935007 |
Approved |
yes |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3610 |
| Permanent link to this record |
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| Author |
Fischer, J.; Cheney, D.L.; Seyfarth, R.M. |
| Title |
Development of infant baboons' responses to graded bark variants |
Type |
Journal Article |
| Year |
2000 |
Publication |
Proceedings. Biological sciences / The Royal Society |
Abbreviated Journal |
Proc Biol Sci |
| Volume |
267 |
Issue |
1459 |
Pages |
2317-2321 |
| Keywords |
*Animal Communication; Animals; Behavior, Animal; Female; Male; Models, Psychological; Papio/growth & development/*physiology; *Vocalization, Animal |
| Abstract |
We studied the development of infant baboons' (Papio cynocephalus ursinus) responses to conspecific 'barks' in a free-ranging population in the Okavango Delta, Botswana. These barks grade from tonal, harmonically rich calls into calls with a more noisy, harsh structure. Typically, tonal variants are given when the signaller is at risk of losing contact with the group or a particular individual ('contact barks'), whereas harsh variants are given in response to predators ('alarm barks'). We conducted focal observations and playback experiments in which we presented variants of barks recorded from resident adult females. By six months of age, infants reliably discriminated between typical alarm and contact barks and they responded more strongly to intermediate alarm calls than to typical contact barks. Infants of six months and older also recognized their mothers by voice. The ability to discriminate between different call variants developed with increasing age. At two and a half months of age, infants failed to respond at all, whereas at four months they responded irrespective of the call type that was presented. At six months, infants showed adult-like responses by responding strongly to alarm barks but ignoring contact barks. We concluded that infants gradually learn to attach the appropriate meaning to alarm and contact barks. |
| Address |
Department of Psychology, University of Pennsylvania, 3815 Walnut Street, Philadelphia, PA 19104, USA. fischerj@eva.mpg.de |
| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0962-8452 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:11413649 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
694 |
| Permanent link to this record |
