Home << 1 2 3 4 5 6 7 8 9 10 >>
List View
 | 
Citations
 | 
Details
   web
Records
Author Sekuler, A.B.; Lee, J.A.; Shettleworth, S.J.
Title Pigeons do not complete partly occluded figures Type Journal Article
Year 1996 Publication Perception Abbreviated Journal Perception
Volume 25 Issue 9 Pages 1109-1120
Keywords Animals; *Columbidae; *Visual Perception
Abstract One of the most common obstacles to object perception is the fact that objects often occlude parts of themselves and parts of other objects. Perceptual completion has been studied extensively in humans, and researchers have shown that humans do complete partly occluded objects. In an effort to understand more about the mechanisms underlying completion, recent research has extended the study of perceptual completion to other mammalian species. Monkeys and mice also seem to complete two-dimensional representations of partly occluded objects. The present study addresses the question of whether this capacity generalizes to a nonmammalian species, the pigeon (Columba livia). The results point to a limit of the generalizability of perceptual completion: pigeons do not complete partly occluded figures.
Address Department of Psychology, University of Toronto, ON, Canada
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0301-0066 ISBN Medium
Area Expedition Conference
Notes PMID:8983050 Approved no
Call Number refbase @ user @ Serial 377
Permanent link to this record
 
 
Author Whiten, A.; Custance, D.M.; Gomez, J.C.; Teixidor, P.; Bard, K.A.
Title Imitative learning of artificial fruit processing in children (Homo sapiens) and chimpanzees (Pan troglodytes) Type Journal Article
Year 1996 Publication Journal of comparative psychology (Washington, D.C. : 1983) Abbreviated Journal J Comp Psychol
Volume 110 Issue 1 Pages 3-14
Keywords Animals; Child, Preschool; Discrimination Learning; Female; Food Preferences/*psychology; *Fruit; Humans; *Imitative Behavior; Male; Mental Recall; Pan troglodytes/*psychology; Social Environment
Abstract Observational learning in chimpanzees and young children was investigated using an artificial fruit designed as an analog of natural foraging problems faced by primates. Each of 3 principal components could be removed in 2 alternative ways, demonstration of only one of which was watched by each subject. This permitted subsequent imitation by subjects to be distinguished from stimulus enhancement. Children aged 2-4 years evidenced imitation for 2 components, but also achieved demonstrated outcomes through their own techniques. Chimpanzees relied even more on their own techniques, but they did imitate elements of 1 component of the task. To our knowledge, this is the first experimental evidence of chimpanzee imitation in a functional task designed to simulate foraging behavior hypothesized to be transmitted culturally in the wild.
Address Scottish Primate Research Group, University of St. Andrews, Fife, Scotland. aw2@st-andrews.ac.uk
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0735-7036 ISBN Medium
Area Expedition Conference
Notes PMID:8851548 Approved no
Call Number refbase @ user @ Serial 744
Permanent link to this record
 
 
Author Waran, N.K.; Robertson, V.; Cuddeford, D.; Kokoszko, A.; Marlin, D.J.
Title Effects of transporting horses facing either forwards or backwards on their behaviour and heart rate Type Journal Article
Year 1996 Publication The Veterinary Record Abbreviated Journal Vet. Rec.
Volume 139 Issue 1 Pages 7-11
Keywords Animals; *Behavior, Animal; Female; *Heart Rate; *Horses; Male; Posture/*physiology; *Transportation
Abstract The effects of transporting horses facing either forwards or backwards were compared by transporting six thoroughbred horses in pairs in a lorry on one journey facing in the direction of travel, and on another journey facing away from the direction of travel, over a standard one-hour route. Heart rate monitors were used to record their heart rate before, during and after the journey and the horses' behaviour was recorded by scan sampling each horse every other minute. The average heart rate was significantly lower (P < 0.05) when the horses were transported facing backwards, and they also tended to rest on their rumps more (P = 0.059). In the forward-facing position, the horses moved more frequently (P < 0.05) and tended to hold their necks in a higher than normal position and to vocalise more frequently (P = 0.059). During loading the average peak heart rate was 38 bpm lower (P < 0.05) when the horses were backed into the horse box for rear-facing transport than when they were loaded facing forwards. However, there was no difference between transport facing forwards or backwards in terms of the peak unloading heart rate, or the average heart rate during loading or unloading. The horses seemed to find being transported less physically stressful when they were facing backwards than when they were facing forwards.
Address Institute of Ecology and Resource Management, University of Edinburgh, School of Agriculture
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0042-4900 ISBN Medium
Area Expedition Conference
Notes PMID:8966985 Approved no
Call Number refbase @ user @ Serial 1938
Permanent link to this record
 
 
Author Fulhorst, C.F.; Hardy, J.L.; Eldridge, B.F.; Chiles, R.E.; Reeves, W.C.
Title Ecology of Jamestown Canyon virus (Bunyaviridae: California serogroup) in coastal California Type Journal Article
Year 1996 Publication The American Journal of Tropical Medicine and Hygiene Abbreviated Journal Am J Trop Med Hyg
Volume 55 Issue 2 Pages 185-189
Keywords Aedes/virology; Animals; Antibodies, Viral/blood; California/epidemiology; Cattle; Cattle Diseases/epidemiology; Deer; Dog Diseases/epidemiology; Dogs; Encephalitis Virus, California/immunology/*isolation & purification; Encephalitis, California/epidemiology/*veterinary; Female; Horse Diseases/epidemiology; Horses; Insect Vectors/virology; Lagomorpha; Male; Neutralization Tests/veterinary; Peromyscus; Rodent Diseases/epidemiology; Sigmodontinae
Abstract This paper reports the first isolation of Jamestown Canyon (JC) virus from coastal California and the results of tests for antibody to JC virus in mammals living in coastal California. The virus isolation was made from a pool of 50 Aedes dorsalis females collected as adults from Morro Bay, San Luis Obispo County, California. The virus isolate was identified by two-way plaque reduction-serum dilution neutralization tests done in Vero cell cultures. Sera from the mammals were tested for antibody to JC virus by a plaque-reduction serum dilution neutralization method. A high prevalence of JC virus-specific antibody was found in horses and cattle sampled from Morro Bay. This finding is additional evidence for the presence of a virus antigenically identical or closely related to JC virus in Morro Bay and indicates that the vectors of the virus in Morro Bay feed on large mammals. A high prevalence of virus-specific antibody was also found in horses sampled from Marin and San Diego counties. This finding suggests that viruses antigenically identical or closely related to JC virus are geographically widespread in coastal California.
Address School of Public Health, University of California, Berkeley, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-9637 ISBN Medium
Area Expedition Conference
Notes PMID:8780458 Approved no
Call Number Equine Behaviour @ team @ Serial 2656
Permanent link to this record
 
 
Author Cilnis, M.J.; Kang, W.; Weaver, S.C.
Title Genetic conservation of Highlands J viruses Type Journal Article
Year 1996 Publication Virology Abbreviated Journal Virology
Volume 218 Issue 2 Pages 343-351
Keywords Alphavirus/*genetics; Alphavirus Infections/transmission/veterinary/virology; Amino Acid Sequence; Animals; Base Sequence; Conserved Sequence; Disease Outbreaks; Encephalitis, Viral/veterinary/virology; *Evolution, Molecular; Horses; Molecular Sequence Data; Phylogeny; RNA, Viral/genetics; Sequence Alignment; Sequence Analysis, DNA; Sequence Homology, Nucleic Acid; Turkeys; Variation (Genetics)/*genetics
Abstract We studied molecular evolution of the mosquito-borne alphavirus Highlands J (HJ) virus by sequencing PCR products generated from 19 strains isolated between 1952 and 1994. Sequences of 1200 nucleotides including portions of the E1 gene and the 3' untranslated region revealed a relatively slow evolutionary rate estimated at 0.9-1.6 x 10(-4) substitutions per nucleotide per year. Phylogenetic trees indicated that all HJ viruses descended from a common ancestor and suggested the presence of one dominant lineage in North America. However, two or more minor lineages probably circulated simultaneously for periods of years to a few decades. Strains isolated from a horse suffering encephalitis, and implicated in a recent turkey outbreak, were not phylogenetically distinct from strains isolated in other locations during the same time periods. Our findings are remarkably similar to those we obtained previously for another North American alphavirus, eastern equine encephalomyelitis virus, with which Highlands J shares primary mosquito and avian hosts, geographical distribution, and ecology. These results support the hypotheses that the duration of the transmission season affects arboviral evolutionary rates and vertebrate host mobility influences genetic diversity.
Address Department of Biology, University of California, San Diego, La Jolla 92093-0116, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0042-6822 ISBN Medium
Area Expedition Conference
Notes PMID:8610461 Approved no
Call Number Equine Behaviour @ team @ Serial 2657
Permanent link to this record
 
 
Author Atwill, E.R.; Mohammed, H.O.; Lopez, J.W.
Title Evaluation of travel and use as a risk factor for seropositivity to Ehrlichia risticii in horses of New York state Type Journal Article
Year 1996 Publication American Journal of Veterinary Research Abbreviated Journal Am J Vet Res
Volume 57 Issue 3 Pages 272-277
Keywords Animals; Cross-Sectional Studies; Ehrlichiosis/epidemiology/*veterinary; Female; *Horse Diseases; Horses; Male; New York/epidemiology; Probability; Random Allocation; Risk Factors; *Travel
Abstract OBJECTIVES--To determine whether mean annual frequency and destination of equine travel was associated with exposure to Ehrlichia risticii and whether these associations were modified by horses' place of residence. DESIGN--Cross-sectional study. SAMPLE POPULATION--511 equine operations containing 2,587 horses were visited in New York state from a target population of 39,000 operations. PROCEDURE--Each horse was tested for serum antibodies against E risticii, using indirect fluorescent antibody. Information on the horse's travel history, farm's management practices, and surrounding ecology was obtained by personal interview and resource maps. Statistical analyses were performed on 2 cohorts of animals: all horses enrolled in the study and horses born on the property or that resided at least 4 years on the farm. Three county-based risk regions (RR) were identified by use of cluster analysis. RESULTS--Mean seroprevalence for each of the 3 RR was 2.4 (low risk), 8.5 (moderate risk), and 18.5% (high risk) for cohort 1 and 2.5, 8.0, and 18.4% for cohort 2. Among cohorts 1 and 2, pleasure riding and breeding trips were associated with exposure to E risticii, but horse residence (low, moderate, or high RR) was an effect modifier for these associations. Among cohort 1 and stratifying the analysis according to the RR for the travel destination, trail riding at low RR and trail riding at high RR were associated with exposure. Among cohort 2 and stratifying the analysis according to the RR for the travel destination, breeding trips were associated with exposure, and strong effect modification was present for horse residence (low, moderate, or high RR). CONCLUSIONS--Only certain types of travel to specific RR were associated with higher risk of exposure to E risticii. In many instances, travel was not associated, or was associated, with a reduced risk of exposure.
Address Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-9645 ISBN Medium
Area Expedition Conference
Notes PMID:8669754 Approved no
Call Number Equine Behaviour @ team @ Serial 2658
Permanent link to this record
 
 
Author Bennett, A.T.
Title Do animals have cognitive maps? Type Journal Article
Year 1996 Publication The Journal of Experimental Biology Abbreviated Journal J Exp Biol
Volume 199 Issue Pt 1 Pages 219-224
Keywords Animals; Cognition/*physiology; Humans; Space Perception/*physiology; Visual Pathways
Abstract Drawing on studies of humans, rodents, birds and arthropods, I show that 'cognitive maps' have been used to describe a wide variety of spatial concepts. There are, however, two main definitions. One, sensu Tolman, O'Keefe and Nadel, is that a cognitive map is a powerful memory of landmarks which allows novel short-cutting to occur. The other, sensu Gallistel, is that a cognitive map is any representation of space held by an animal. Other definitions with quite different meanings are also summarised. I argue that no animal has been conclusively shown to have a cognitive map, sensu Tolman, O'Keefe and Nadel, because simpler explanations of the crucial novel short-cutting results are invariably possible. Owing to the repeated inability of experimenters to eliminate these simpler explanations over at least 15 years, and the confusion caused by the numerous contradictory definitions of a cognitive map, I argue that the cognitive map is no longer a useful hypothesis for elucidating the spatial behaviour of animals and that use of the term should be avoided.
Address Department of Pure Mathematics, University of Adelaide, Australia
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-0949 ISBN Medium
Area Expedition Conference
Notes PMID:8576693 Approved no
Call Number Equine Behaviour @ team @ Serial 2756
Permanent link to this record
 
 
Author Gallistel, C.R.; Cramer, A.E.
Title Computations on metric maps in mammals: getting oriented and choosing a multi-destination route Type Journal Article
Year 1996 Publication The Journal of Experimental Biology Abbreviated Journal J Exp Biol
Volume 199 Issue Pt 1 Pages 211-217
Keywords Animals; Brain/physiology; Cercopithecus aethiops; Cognition/*physiology; Humans; Mammals/*physiology; Movement; Orientation/*physiology; Rats; Space Perception; Visual Pathways/*physiology
Abstract The capacity to construct a cognitive map is hypothesized to rest on two foundations: (1) dead reckoning (path integration); (2) the perception of the direction and distance of terrain features relative to the animal. A map may be constructed by combining these two sources of positional information, with the result that the positions of all terrain features are represented in the coordinate framework used for dead reckoning. When animals need to become reoriented in a mapped space, results from rats and human toddlers indicate that they focus exclusively on the shape of the perceived environment, ignoring non-geometric features such as surface colors. As a result, in a rectangular space, they are misoriented half the time even when the two ends of the space differ strikingly in their appearance. In searching for a hidden object after becoming reoriented, both kinds of subjects search on the basis of the object's mapped position in the space rather than on the basis of its relationship to a goal sign (e.g. a distinctive container or nearby marker), even though they have demonstrably noted the relationship between the goal and the goal sign. When choosing a multidestination foraging route, vervet monkeys look at least three destinations ahead, even though they are only capable of keeping a maximum of six destinations in mind at once.
Address Department of Psychology, University of California, Los Angeles 90095, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-0949 ISBN Medium
Area Expedition Conference
Notes PMID:8576692 Approved no
Call Number Equine Behaviour @ team @ Serial 2757
Permanent link to this record
 
 
Author Etienne, A.S.; Maurer, R.; Seguinot, V.
Title Path integration in mammals and its interaction with visual landmarks Type Journal Article
Year 1996 Publication The Journal of Experimental Biology Abbreviated Journal J Exp Biol
Volume 199 Issue Pt 1 Pages 201-209
Keywords Animals; Cognition/physiology; Cricetinae; Gerbillinae; Humans; Locomotion/*physiology; Mammals/*physiology; Mesocricetus; Mice; Proprioception/physiology; Rats; Visual Pathways/*physiology; Visual Perception/*physiology
Abstract During locomotion, mammals update their position with respect to a fixed point of reference, such as their point of departure, by processing inertial cues, proprioceptive feedback and stored motor commands generated during locomotion. This so-called path integration system (dead reckoning) allows the animal to return to its home, or to a familiar feeding place, even when external cues are absent or novel. However, without the use of external cues, the path integration process leads to rapid accumulation of errors involving both the direction and distance of the goal. Therefore, even nocturnal species such as hamsters and mice rely more on previously learned visual references than on the path integration system when the two types of information are in conflict. Recent studies investigate the extent to which path integration and familiar visual cues cooperate to optimize the navigational performance.
Address Laboratoire d'Ethologie, FPSE, Universite de Geneve, Carouge, Switzerland
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-0949 ISBN Medium
Area Expedition Conference
Notes PMID:8576691 Approved no
Call Number Equine Behaviour @ team @ Serial 2758
Permanent link to this record
 
 
Author Wasserman, E.A.; Gagliardi, J.L.; Cook, B.R.; Kirkpatrick-Steger, K.; Astley, S.L.; Biederman, I.
Title The pigeon's recognition of drawings of depth-rotated stimuli Type Journal Article
Year 1996 Publication Journal of Experimental Psychology. Animal Behavior Processes Abbreviated Journal J Exp Psychol Anim Behav Process
Volume 22 Issue 2 Pages 205-221
Keywords Animals; Cognition/*physiology; Columbidae; Discrimination (Psychology); Form Perception/*physiology; Learning/*physiology; Photic Stimulation; Rotation
Abstract Four experiments used a four-choice discrimination learning paradigm to explore the pigeon's recognition of line drawings of four objects (an airplane, a chair, a desk lamp, and a flashlight) that were rotated in depth. The pigeons reliably generalized discriminative responding to pictorial stimuli over all untrained depth rotations, despite the bird's having been trained at only a single depth orientation. These generalization gradients closely resembled those found in prior research that used other stimulus dimensions. Increasing the number of different vantage points in the training set from one to three broadened the range of generalized testing performance, with wider spacing of the training orientations more effectively broadening generalized responding. Template and geon theories of visual recognition are applied to these empirical results.
Address Department of Psychology, University of Iowa, Iowa City 52242-1407, USA. ed-wasserman@uiowa.educ
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0097-7403 ISBN Medium
Area Expedition Conference
Notes PMID:8618103 Approved no
Call Number Equine Behaviour @ team @ Serial 2780
Permanent link to this record