| |
Records |
Links |
|
Author |
Ferkin, M.H.; Pierce, A.A.; Sealand, R.O.; Delbarco-Trillo, J. |
|
| |
Title |
Meadow voles, Microtus pennsylvanicus, can distinguish more over-marks from fewer over-marks |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
8 |
Issue |
3 |
Pages |
182-189 |
|
| |
Keywords |
Animals; Arvicolinae/*psychology; *Discrimination Learning; Female; Intermediate Filament Proteins; Male; Mathematics; Sex Factors; *Smell |
|
| |
Abstract |
Is it possible that voles have a sense of number? To address this question, we determined whether voles discriminate between two different scent-marking individuals and identify the individual whose scent marks was on top more often than the other individual. We tested whether voles show a preference for the individual whose scent marks was on top most often. If so, the simplest explanation was that voles can make a relative size judgement-such as distinguishing an area containing more of one individual's over-marks as compared to less of another individual's over-marks. We found that voles respond preferentially to the donor that provided a greater number of over-marks as compared to the donor that provided a lesser number of over-marks. Thus, we concluded that voles might display the capacity for relative numerousness. Interestingly, female voles were better able than male voles to distinguish between small differences in the relative number of over-marks by the two scent donors. |
|
| |
Address |
Department of Biology, The University of Memphis, Ellington Hall, Memphis, TN 38152, USA. mhferkin@memphis.edu |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1435-9448 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference  |
|
|
| |
Notes |
PMID:15580367 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2501 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Werner, C.W.; Tiemann, I.; Cnotka, J.; Rehkamper, G. |
|
| |
Title |
Do chickens (Gallus gallus f. domestica) decompose visual figures? |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
8 |
Issue |
2 |
Pages |
129-140 |
|
| |
Keywords |
Animals; *Chickens; Conditioning, Classical; *Discrimination Learning; Female; *Pattern Recognition, Visual; Photic Stimulation; *Visual Perception |
|
| |
Abstract |
To investigate whether learning to discriminate between visual compound stimuli depends on decomposing them into constituting features, hens were first trained to discriminate four features (red, green, horizontal, vertical) from two dimensions (colour, line orientation). After acquisition, hens were trained with compound stimuli made up from these dimensions in two ways: a separable (line on a coloured background) stimulus and an integral one (coloured line). This compound training included a reversal of reinforcement of only one of the two dimensions (half-reversal). After having achieved the compound stimulus discrimination, a second dimensional training identical to the first was performed. Finally, in the second compound training the other dimension was reversed. Two major results were found: (1) an interaction between the dimension reversed and the type of compound stimulus: in compound training with colour reversal, separable compound stimuli were discriminated worse than integral compounds and vice versa in compound training with line orientation reversed. (2) Performance in the second compound training was worse than in the first one. The first result points to a similar mode of processing for separable and integral compounds, whereas the second result shows that the whole stimulus is psychologically superior to its constituting features. Experiment 2 repeated experiment 1 using line orientation stimuli of reversed line and background brightness. Nevertheless, the results were similar to experiment 1. Results are discussed in the framework of a configural exemplar theory of discrimination that assumes the representation of the whole stimulus situation combined with transfer based on a measure of overall similarity. |
|
| |
Address |
C. and O. Vogt Institute of Brain Research, Heinrich Heine University Dusseldorf, Universitatsstr. 1, 40225, Dusseldorf, Germany. wernerc@uni-duesseldorf.de |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1435-9448 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15490291 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2503 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Zucca, P.; Antonelli, F.; Vallortigara, G. |
|
| |
Title |
Detour behaviour in three species of birds: quails (Coturnix sp.), herring gulls (Larus cachinnans) and canaries (Serinus canaria) |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
8 |
Issue |
2 |
Pages |
122-128 |
|
| |
Keywords |
Animals; *Avoidance Learning; *Birds; Canaries; Charadriiformes; Coturnix; *Discrimination Learning; Orientation; *Space Perception; *Spatial Behavior; Species Specificity |
|
| |
Abstract |
Detour behaviour is the ability of an animal to reach a goal stimulus by moving round any interposed obstacle. It has been widely studied and has been proposed as a test of insight learning in several species of mammals, but few data are available in birds. A comparative study in three species of birds, belonging to different eco-ethological niches, allows a better understanding of the cognitive mechanism of such detour behaviour. Young quails (Coturnix sp.), herring gulls (Larus cachinnans) and canaries (Serinus canaria), 1 month old, 10-25 days old and 4-6 months old, respectively, were tested in a detour situation requiring them to abandon a clear view of a biologically interesting object (their own reflection in a mirror) in order to approach that object. Birds were placed in a closed corridor, at one end of which was a barrier through which the object was visible. Four different types of barrier were used: vertical bar, horizontal bar, grid and transparent. Two symmetrical apertures placed midline in the corridor allowed the birds to adopt routes passing around the barrier. After entering the apertures, birds could turn either right or left to re-establish social contact with the object in the absence of any local sensory cues emanating from it. Quails appeared able to solve the task, though their performance depended on the type of barrier used, which appeared to modulate their relative interest in approaching the object or in exploring the surroundings. Young herring gulls also showed excellent abilities to locate spatially the out-of-view object, except when the transparent barrier was used. Canaries, on the other hand, appeared completely unable to solve the detour task, whatever barrier was in use. It is suggested that these species differences can be accounted for in terms of adaptation to a terrestrial or aerial environment. |
|
| |
Address |
Laboratory of Animal Cognition and Comparative Neuroscience, Department of Psychology, University of Trieste, Via S. Anastasio 12, 34100, Trieste, Italy. zucca@units.it |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1435-9448 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15449104 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2506 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Gazit, I.; Goldblatt, A.; Terkel, J. |
|
| |
Title |
The role of context specificity in learning: the effects of training context on explosives detection in dogs |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
8 |
Issue |
3 |
Pages |
143-150 |
|
| |
Keywords |
Animals; *Association Learning; Conditioning, Classical; *Discrimination Learning; Dogs; *Environment; *Generalization, Stimulus; *Smell |
|
| |
Abstract |
Various experiments revealed that if an animal learns a stimulus-response-reinforcer relationship in one context and is then tested in another context there is usually a lessening of stimulus control, and the same discriminative stimuli that reliably controlled the behavior in the first context will have less effect in the new context. This reduction in performance is known as the “context shift effect.” The effect of changing context on the probability of detecting explosives was investigated in seven highly trained explosives detection dogs (EDDs). In experiment 1 the dogs were trained alternately on path A, which always had five hidden explosives, and on a very similar path B, which never had any explosives. Within a few sessions the dogs showed a significant decrease in search behavior on path B, but not on path A. In experiment 2 the same dogs were trained only on path B with a target density of one explosive hidden every 4th day. The probability of the dogs now detecting the explosive was found to be significantly lower than in experiment 1. In experiment 3 the effect of the low target density as used in experiment 2 was investigated on a new but very similar path C. Both the detection probability for the one explosive every 4th day on the new path and the motivation to search were significantly higher than found in experiment 2. Finally, in experiment 4, an attempt was made to recondition the dogs to search on path B. Although trained for 12 daily sessions with one explosive hidden every session, the dogs failed to regain the normal levels of motivation they had shown on both new paths and on the paths that they knew usually contained explosives. The findings reveal that even a very intensively trained EDD will rapidly learn that a specific stretch of path does not contain explosives. The dog will then be less motivated to search and will miss newly placed targets. This learning is specific to the formerly always-clean path and is to some extent irreversible. However, the dog will search and detect normally on new paths even if they are very similar to the always-clean path. The data are discussed in terms of variables affecting renewal. The results suggest that following training designed to make a behavior “context independent,” any extinction training will not generalize beyond that specific context used during the extinction training. In addition, if the behavior is extinguished in a specific context, it will be very difficult to restore that behavior in that context. These conclusions should be considered by anyone attempting to extinguish well-established trans-context behaviors. |
|
| |
Address |
Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 69978, Israel. iritgazi@post.tau.ac.il |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1435-9448 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15449101 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2509 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Treichler, F.R. |
|
| |
Title |
Successive reversal of concurrent discriminations by macaques (Macaca mulatta): proactive interference effects |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
8 |
Issue |
2 |
Pages |
75-83 |
|
| |
Keywords |
Animals; Choice Behavior; *Discrimination Learning; Female; Macaca mulatta/*psychology; *Memory; *Proactive Inhibition; Random Allocation; *Reversal Learning |
|
| |
Abstract |
Rhesus monkeys received concurrent within-session training on eight, two-choice object pairs and then underwent successive reversals of these problems. Initially, reversals required about six times more training than acquisition with no improvement over seven successive reversals. Surprisingly, performance on these eight problems was unimpaired if they were embedded in different eight-problem tasks, thereby indicating a release from proactive interference. When the original eight problems again underwent successive reversal, no improvement was seen over seven reversals, although there was significantly less error-per-reversal than in the initial test. Subsequently, monkeys appeared to be developing a learning set for successive reversal because performance on successive reversal of eight novel problems was not different from that seen with the old familiar task. Set acquisition was confirmed when proficient reversal was eventually achieved on both old and new concurrent tasks. Thus, “concurrent reversal set” did develop, but it required arduous training to overcome proactive interference effects on memory. The ubiquitous influence of measurement context on organization of monkey memory was noted. |
|
| |
Address |
Kent State University, Kent, Ohio 44242, USA. rtreichl@kent.edu |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1435-9448 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15365875 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2512 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Bovet, D.; Vauclair, J.; Blaye, A. |
|
| |
Title |
Categorization and abstraction abilities in 3-year-old children: a comparison with monkey data |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
8 |
Issue |
1 |
Pages |
53-59 |
|
| |
Keywords |
Animals; Child Development; Child, Preschool; *Classification; *Concept Formation; *Discrimination Learning; Female; *Form Perception; Humans; Male; Papio; Pattern Recognition, Visual; *Problem Solving; Species Specificity |
|
| |
Abstract |
Three-year-old children were tested on three categorization tasks of increasing levels of abstraction (used with adult baboons in an earlier study): the first was a conceptual categorization task (food vs toys), the second a perceptual matching task (same vs different objects), and the third a relational matching task in which the children had to sort pairs according to whether or not the two items belonged to the same or different categories. The children were tested using two different procedures, the first a replication of the procedure used with the baboons (pulling one rope for a category or a relationship between two objects, and another rope for the other category or relationship), the second a task based upon children's prior experiences with sorting objects (putting in the same box objects belonging to the same category or a pair of objects exemplifying the same relation). The children were able to solve the first task (conceptual categorization) when tested with the sorting into boxes procedure, and the second task (perceptual matching) when tested with both procedures. The children were able to master the third task (relational matching) only when the rules were clearly explained to them, but not when they could only watch sorting examples. In fact, the relational matching task without explanation requires analogy abilities that do not seem to be fully developed at 3 years of age. The discrepancies in performances between children tested with the two procedures, with the task explained or not, and the discrepancies observed between children and baboons are discussed in relation to differences between species and/or problem-solving strategies. |
|
| |
Address |
Center for Research in Psychology of Cognition, Language and Emotion, Universite de Provence, Aix-en-Provence, France. dbovet@u-paris10.fr |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1435-9448 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15300466 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2516 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Evans, T.A.; Westergaard, G.C. |
|
| |
Title |
Discrimination of functionally appropriate and inappropriate throwing tools by captive tufted capuchins (Cebus apella) |
Type |
Journal Article |
| |
Year |
2004 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
7 |
Issue |
4 |
Pages |
255-262 |
|
| |
Keywords |
Animals; Appetitive Behavior; Cebus/*psychology; Choice Behavior; *Concept Formation; *Discrimination Learning; Female; Male; *Problem Solving; *Psychomotor Performance; Recognition (Psychology) |
|
| |
Abstract |
A tool-throwing task was used to test whether capuchin monkeys understand the difference between functionally appropriate and functionally inappropriate tools. A group of monkeys was trained to obtain a sticky treat from a container outside their enclosure using a projectile attached to one end of an anchored line. Subsequently, these monkeys were given choice tests between functional and nonfunctional versions of tools used in training. A different feature of the tool was varied between alternatives in each choice test. The monkeys chose to use functional tools significantly more often than nonfunctional tools in early exposures to each choice test. A second experiment tested whether these subjects, as well as a second group of minimally trained participants, could distinguish between functional and nonfunctional tools that appeared different from those used in training. A new set of design features was varied between tools in these choice tests. All participants continued to choose functional tools significantly more often than nonfunctional tools, regardless of their tool-throwing experience or the novel appearance of the tools. These results suggest that capuchin monkeys, like chimpanzees studied in similar experiments, are sensitive to a variety of functionally relevant tool features. |
|
| |
Address |
Alpha Genesis Inc., 95 Castle Hall Road, P.O. Box 557, Yemassee, SC 29945, USA. teprimate@islc.net |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1435-9448 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15138849 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2523 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Hampton, R.R.; Zivin, A.; Murray, E.A. |
|
| |
Title |
Rhesus monkeys (Macaca mulatta) discriminate between knowing and not knowing and collect information as needed before acting |
Type |
Journal Article |
| |
Year |
2004 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
7 |
Issue |
4 |
Pages |
239-246 |
|
| |
Keywords |
Animals; Association Learning; *Awareness; Choice Behavior; *Concept Formation; *Discrimination Learning; Female; Macaca mulatta/*psychology; Male; *Memory, Short-Term; Observation |
|
| |
Abstract |
Humans use memory awareness to determine whether relevant knowledge is available before acting, as when we determine whether we know a phone number before dialing. Such metacognition, or thinking about thinking, can improve selection of appropriate behavior. We investigated whether rhesus monkeys ( Macaca mulatta) are capable of a simple form of metacognitive access to the contents of short-term memory. Monkeys chose among four opaque tubes, one of which concealed food. The tube containing the reward varied randomly from trial to trial. On half the trials the monkeys observed the experimenter baiting the tube, whereas on the remaining trials their view of the baiting was blocked. On each trial, monkeys were allowed a single chance to select the tube containing the reward. During the choice period the monkeys had the opportunity to look down the length of each tube, to determine if it contained food. When they knew the location of the reward, most monkeys chose without looking. In contrast, when ignorant, monkeys often made the effort required to look, thereby learning the location of the reward before choosing. Looking improved accuracy on trials on which monkeys had not observed the baiting. The difference in looking behavior between trials on which the monkeys knew, and trials on which they were ignorant, suggests that rhesus monkeys discriminate between knowing and not knowing. This result extends similar observations made of children and apes to a species of Old World monkey, suggesting that the underlying cognitive capacities may be widely distributed among primates. |
|
| |
Address |
Section on the Neurobiology of Learning and Memory, Laboratory of Neuropsychology, National Institute of Mental Health, NIH, Bethesda, MD 20892-4415, USA. robert@ln.nimh.nih.gov |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1435-9448 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15105996 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2525 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Yamazaki, Y.; Shinohara, N.; Watanabe, S. |
|
| |
Title |
Visual discrimination of normal and drug induced behavior in quails (Coturnix coturnix japonica) |
Type |
Journal Article |
| |
Year |
2004 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
7 |
Issue |
2 |
Pages |
128-132 |
|
| |
Keywords |
Animals; Behavior, Animal/*drug effects; Classification; Coturnix/*physiology; *Discrimination Learning; *Generalization (Psychology); Ketamine/pharmacology; Male; Methamphetamine/pharmacology; *Pattern Recognition, Visual; Video Recording; Visual Perception |
|
| |
Abstract |
The ability to discriminate the physical states of others could be an adaptive behavior, especially for social animals. For example, the ability to discriminate illness behavior would be helpful for avoiding spoiled foods. We report on an experiment with Japanese quails testing whether these birds can discriminate the physical states of conspecifics. The quails were trained to discriminate between moving video images of quails injected with psychoactive drugs and those in a normal (not injected) condition. Methamphetamine (stimulant) or ketamine (anesthetic) were used to produce drug-induced behaviors in conspecifics. The former induced hyperactive behavior and the latter hypoactive behavior. The subject quails could learn the discrimination and showed generalization to novel images of the drug-induced behaviors. They did not, however, show discriminative behavior according to the type and dosage of the drugs. Thus, they categorized the behavior not on the basis of degree of activity, but on the basis of abnormality. |
|
| |
Address |
Biopsychologie, Institut fur Kognitive Neurowissenschaft, Fakultat fur Psychologie, Ruhr-Universitat Bochum, 44780 Bochum, Germany. yumyam@bio.psy.ruhr-uni-bochum.de |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1435-9448 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15069613 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2527 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Chappell, J.; Kacelnik, A. |
|
| |
Title |
Selection of tool diameter by New Caledonian crows Corvus moneduloides |
Type |
Journal Article |
| |
Year |
2004 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
7 |
Issue |
2 |
Pages |
121-127 |
|
| |
Keywords |
Animals; Behavior, Animal; *Choice Behavior; Discrimination Learning; *Feeding Behavior; Female; Functional Laterality; *Manufactured Materials; *Plant Leaves; *Problem Solving; *Songbirds; Technology |
|
| |
Abstract |
One important element of complex and flexible tool use, particularly where tool manufacture is involved, is the ability to select or manufacture appropriate tools anticipating the needs of any given task-an ability that has been rarely tested in non-primates. We examine aspects of this ability in New Caledonian crows-a species known to be extraordinary tool users and manufacturers. In a 2002 study, Chappell and Kacelnik showed that these crows were able to select a tool of the appropriate length for a task among a set of different lengths, and in 2002, Weir, Chappell and Kacelnik showed that New Caledonian crows were able to shape unfamiliar materials to create a usable tool for a specific task. Here we examine their handling of tool diameter. In experiment 1, we show that when facing three loose sticks that were usable as tools, they preferred the thinnest one. When the three sticks were presented so that one was loose and the other two in a bundle, they only disassembled the bundle when their preferred tool was tied. In experiment 2, we show that they manufacture, and modify during use, a tool of a suitable diameter from a tree branch, according to the diameter of the hole through which the tool will have to be inserted. These results add to the developing picture of New Caledonian crows as sophisticated tool users and manufacturers, having an advanced level of folk physics. |
|
| |
Address |
Department of Zoology, South Parks Road, OX1 3PS, Oxford, UK. jackie.chappell@zoo.ox.ac.uk |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1435-9448 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15069612 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2528 |
|
| Permanent link to this record |
