| |
Records |
Links |
|
Author |
Clutton-Brock, T.H.; Russell, A.F.; Sharpe, L.L.; Brotherton, P.N.; McIlrath, G.M.; White, S.; Cameron, E.Z. |
|
| |
Title |
Effects of helpers on juvenile development and survival in meerkats |
Type |
Journal Article |
| |
Year |
2001 |
Publication |
Science (New York, N.Y.) |
Abbreviated Journal |
Science |
|
| |
Volume |
293 |
Issue |
5539 |
Pages |
2446-2449 |
|
| |
Keywords |
Animals; Breeding; Carnivora/growth & development/*physiology; *Cooperative Behavior; Feeding Behavior; Female; Male; Survival Rate; *Weight Gain |
|
| |
Abstract |
Although breeding success is known to increase with group size in several cooperative mammals, the mechanisms underlying these relationships are uncertain. We show that in wild groups of cooperative meerkats, Suricata suricatta, reductions in the ratio of helpers to pups depress the daily weight gain and growth of pups and the daily weight gain of helpers. Increases in the daily weight gain of pups are associated with heavier weights at independence and at 1 year of age, as well as with improved foraging success as juveniles and higher survival rates through the first year of life. These results suggest that the effects of helpers on the fitness of pups extend beyond weaning and that helpers may gain direct as well as indirect benefits by feeding pups. |
|
| |
Address |
Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK. thcb@hermes.cam.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 |
0036-8075 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:11577235 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial  |
414 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Cameron, E.Z.; du Toit, J.T. |
|
| |
Title |
Winning by a neck: tall giraffes avoid competing with shorter browsers |
Type |
Journal Article |
| |
Year |
2007 |
Publication |
The American naturalist |
Abbreviated Journal |
Am Nat |
|
| |
Volume |
169 |
Issue |
1 |
Pages |
130-135 |
|
| |
Keywords |
Acacia/growth & development; Animals; Feeding Behavior/*physiology; Neck/*anatomy & histology; Plant Leaves/growth & development; Ruminants/*anatomy & histology/*physiology; South Africa |
|
| |
Abstract |
With their vertically elongated body form, giraffes generally feed above the level of other browsers within the savanna browsing guild, despite having access to foliage at lower levels. They ingest more leaf mass per bite when foraging high in the tree, perhaps because smaller, more selective browsers deplete shoots at lower levels or because trees differentially allocate resources to promote shoot growth in the upper canopy. We erected exclosures around individual Acacia nigrescens trees in the greater Kruger ecosystem, South Africa. After a complete growing season, we found no differences in leaf biomass per shoot across height zones in excluded trees but significant differences in control trees. We conclude that giraffes preferentially browse at high levels in the canopy to avoid competition with smaller browsers. Our findings are analogous with those from studies of grazing guilds and demonstrate that resource partitioning can be driven by competition when smaller foragers displace larger foragers from shared resources. This provides the first experimental support for the classic evolutionary hypothesis that vertical elongation of the giraffe body is an outcome of competition within the browsing ungulate guild. |
|
| |
Address |
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa. ezcameron@zoology.up.ac.za |
|
| |
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 |
1537-5323 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:17206591 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
410 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Hampton, R.R.; Shettleworth, S.J. |
|
| |
Title |
Hippocampus and memory in a food-storing and in a nonstoring bird species |
Type |
Journal Article |
| |
Year |
1996 |
Publication |
Behavioral neuroscience |
Abbreviated Journal |
Behav Neurosci |
|
| |
Volume |
110 |
Issue |
5 |
Pages |
946-964 |
|
| |
Keywords |
Animals; Appetitive Behavior/*physiology; Attention/physiology; Birds/*physiology; Brain Mapping; Feeding Behavior/*physiology; Mental Recall/*physiology; Organ Size/physiology; Orientation/*physiology; Retention (Psychology)/physiology; Species Specificity |
|
| |
Abstract |
Food-storing birds maintain in memory a large and constantly changing catalog of the locations of stored food. The hippocampus of food-storing black-capped chickadees (Parus atricapillus) is proportionally larger than that of nonstoring dark-eyed juncos (Junco hyemalis). Chickadees perform better than do juncos in an operant test of spatial non-matching-to-sample (SNMTS), and chickadees are more resistant to interference in this paradigm. Hippocampal lesions attenuate performance in SNMTS and increase interference. In tests of continuous spatial alternation (CSA), juncos perform better than chickadees. CSA performance also declines following hippocampal lesions. By itself, sensitivity of a given task to hippocampal damage does not predict the direction of memory differences between storing and nonstoring species. |
|
| |
Address |
Department of Psychology, University of Toronto, Ontario, Canada. 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 |
0735-7044 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:8918998 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
375 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Jones, J.E.; Antoniadis, E.; Shettleworth, S.J.; Kamil, A.C. |
|
| |
Title |
A comparative study of geometric rule learning by nutcrackers (Nucifraga columbiana), pigeons (Columba livia), and jackdaws (Corvus monedula) |
Type |
Journal Article |
| |
Year |
2002 |
Publication |
Journal of comparative psychology (Washington, D.C. : 1983) |
Abbreviated Journal |
J Comp Psychol |
|
| |
Volume |
116 |
Issue |
4 |
Pages |
350-356 |
|
| |
Keywords |
Animals; Behavior, Animal/physiology; Birds; Feeding Behavior/physiology; Learning/*physiology; *Mathematics; Random Allocation; Spatial Behavior/*physiology |
|
| |
Abstract |
Three avian species, a seed-caching corvid (Clark's nutcrackers; Nucifraga columbiana), a non-seed-caching corvid (jackdaws; Corvus monedula), and a non-seed-caching columbid (pigeons; Columba livia), were tested for ability to learn to find a goal halfway between 2 landmarks when distance between the landmarks varied during training. All 3 species learned, but jackdaws took much longer than either pigeons or nutcrackers. The nutcrackers searched more accurately than either pigeons or jackdaws. Both nutcrackers and pigeons showed good transfer to novel landmark arrays in which interlandmark distances were novel, but inconclusive results were obtained from jackdaws. Species differences in this spatial task appear quantitative rather than qualitative and are associated with differences in natural history rather than phylogeny. |
|
| |
Address |
School of Biological Sciences, University of Nebraska-Lincoln, 68588-0118, USA |
|
| |
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 |
0735-7036 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:12539930 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
369 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Shettleworth, S.J. |
|
| |
Title |
Memory and hippocampal specialization in food-storing birds: challenges for research on comparative cognition |
Type |
Journal Article |
| |
Year |
2003 |
Publication |
Brain, behavior and evolution |
Abbreviated Journal |
Brain Behav Evol |
|
| |
Volume |
62 |
Issue |
2 |
Pages |
108-116 |
|
| |
Keywords |
Animals; Birds/*physiology; Cognition/*physiology; Color Perception/physiology; Feeding Behavior/*physiology; Hippocampus/*physiology; Memory/*physiology; Species Specificity |
|
| |
Abstract |
The three-way association among food-storing behavior, spatial memory, and hippocampal enlargement in some species of birds is widely cited as an example of a new 'cognitive ecology' or 'neuroecology.' Whether this relationship is as strong as it first appears and whether it might be evidence for an adaptive specialization of memory and hippocampus in food-storers have recently been the subject of some controversy [Bolhuis and Macphail, 2001; Macphail and Bolhuis, 2001]. These critiques are based on misconceptions about the nature of adaptive specializations in cognition, misconceptions about the uniformity of results to be expected from applying the comparative method to data from a wide range of species, and a narrow view of what kinds of cognitive adaptations are theoretically interesting. New analyses of why food-storers (black-capped chickadees, Poecile Atricapilla) respond preferentially to spatial over color cues when both are relevant in a memory task show that this reflects a relative superiority of spatial memory as compared to memory for color rather than exceptional spatial attention or spatial discrimination ability. New studies of chickadees from more or less harsh winter climates also support the adaptive specialization hypothesis and suggest that within-species comparisons may be especially valuable for unraveling details of the relationships among ecology, memory, and brain in food-storing species. |
|
| |
Address |
Department of Psychology, University of Toronto, Toronto, Ont., M5S 3G3, Canada. shettle@psych.utoronto.ca |
|
| |
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 |
0006-8977 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:12937349 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
367 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Shettleworth, S.J.; Sutton, J.E. |
|
| |
Title |
Multiple systems for spatial learning: dead reckoning and beacon homing in rats |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Journal of experimental psychology. Animal behavior processes |
Abbreviated Journal |
J Exp Psychol Anim Behav Process |
|
| |
Volume |
31 |
Issue |
2 |
Pages |
125-141 |
|
| |
Keywords |
Animals; Behavior, Animal; Cues; *Feeding Behavior; Habituation, Psychophysiologic; *Homing Behavior; *Learning; Male; Rats; Rats, Long-Evans; *Space Perception |
|
| |
Abstract |
Rats homed with food in a large lighted arena. Without visual cues, they used dead reckoning. When a beacon indicated the home, rats could also use the beacon. Homing did not differ in 2 groups of rats, 1 provided with the beacon and 1 without it; tests without the beacon gave no evidence that beacon learning overshadowed dead reckoning (Experiment 1). When the beacon was at the home for 1 group and in random locations for another, there was again no evidence of cue competition (Experiment 2). Dead reckoning experience did not block acquisition of beacon homing (Experiment 3). Beacon learning and dead reckoning do not compete for predictive value but acquire information in parallel and are used hierarchically. |
|
| |
Address |
Department of Psychology, University of Toronto, Toronto, ON M5S 3G3, Canada. shettle@psych.utoronto.ca |
|
| |
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 |
0097-7403 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15839771 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
364 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Shettleworth, S.J. |
|
| |
Title |
Animal behaviour: planning for breakfast |
Type |
Journal Article |
| |
Year |
2007 |
Publication |
Nature |
Abbreviated Journal |
Nature |
|
| |
Volume |
445 |
Issue |
7130 |
Pages |
825-826 |
|
| |
Keywords |
Animals; Feeding Behavior/*physiology; *Food; Haplorhini/physiology; Memory/physiology; Songbirds/*physiology; Thinking/*physiology |
|
| |
Abstract |
|
|
| |
Address |
|
|
| |
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 |
1476-4687 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:17314961 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
356 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ottoni, E.B.; de Resende, B.D.; Izar, P. |
|
| |
Title |
Watching the best nutcrackers: what capuchin monkeys (Cebus apella) know about others' tool-using skills |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Animal cognition |
Abbreviated Journal |
Anim. Cogn. |
|
| |
Volume |
8 |
Issue |
4 |
Pages |
215-219 |
|
| |
Keywords |
Animals; *Association Learning; Cebus/*psychology; *Feeding Behavior; Female; Male; Nuts; *Problem Solving |
|
| |
Abstract |
The present work is part of a decade-long study on the spontaneous use of stones for cracking hard-shelled nuts by a semi-free-ranging group of brown capuchin monkeys (Cebus apella). Nutcracking events are frequently watched by other individuals--usually younger, less proficient, and that are well tolerated to the point of some scrounging being allowed by the nutcracker. Here we report findings showing that the choice of observational targets is an active, non-random process, and that observers seem to have some understanding of the relative proficiency of their group mates, preferentially watching the more skilled nutcrackers, which enhances not only scrounging payoffs, but also social learning opportunities. |
|
| |
Address |
Laboratory of Cognitive Ethology, Department of Experimental Psychology, Institute of Psychology, University of Sao Paulo, Brazil. ebottoni@usp.br |
|
| |
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:15719240 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
355 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Zentall, T.R.; Sherburne, L.M. |
|
| |
Title |
Role of differential sample responding in the differential outcomes effect involving delayed matching by pigeons |
Type |
Journal Article |
| |
Year |
1994 |
Publication |
Journal of experimental psychology. Animal behavior processes |
Abbreviated Journal |
J Exp Psychol Anim Behav Process |
|
| |
Volume |
20 |
Issue |
4 |
Pages |
390-401 |
|
| |
Keywords |
Animals; Behavior, Animal; Choice Behavior; *Columbidae; *Discrimination Learning; Feeding Behavior; Task Performance and Analysis |
|
| |
Abstract |
The role of differential sample responding in the differential outcomes effect was examined. In Experiment 1, we trained pigeons on a one-to-many matching task with differential sample responding required. Differential outcomes were associated with samples and comparisons, with comparisons only, or with neither samples nor comparisons. Slopes of delay functions for trials with pecked versus nonpecked samples suggested use of a single-code-default strategy in the nondifferential-outcomes group but not in the differential-outcomes groups. In Experiment 2, differential sample responding and differential outcomes were manipulated independently. Again, there were significant differences in the relative slopes of the delay functions. Results suggest that differential outcomes exert their effect independently of differential sample responding. |
|
| |
Address |
Department of Psychology, University of Kentucky, Lexington 40506 |
|
| |
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 |
0097-7403 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:7964521 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
257 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Friedrich, A.M.; Zentall, T.R. |
|
| |
Title |
Pigeons shift their preference toward locations of food that take more effort to obtain |
Type |
Journal Article |
| |
Year |
2004 |
Publication |
Behavioural processes |
Abbreviated Journal |
Behav. Process. |
|
| |
Volume |
67 |
Issue |
3 |
Pages |
405-415 |
|
| |
Keywords |
Animals; *Behavior, Animal; *Choice Behavior; Columbidae; *Exertion; *Feeding Behavior; Reward |
|
| |
Abstract |
Although animals typically prefer to exert less effort rather than more effort to obtain food, the present research shows that requiring greater effort to obtain food at a particular location appears to increase the value of that location. In Experiment 1, pigeons' initial preference for one feeder was significantly reduced by requiring 1 peck to obtain food from that feeder and requiring 30 pecks to obtain food from the other feeder. In Experiment 2, a similar decrease in preference was not found when pigeons received reinforcement from both feeders independently of the amount of effort required. These results are consistent with the within-trial contrast effect proposed by in which the relative hedonic value of a reward depends on the state of the animal immediately prior to the reward. The greater the improvement from that prior state the greater the value of the reinforcer. |
|
| |
Address |
Department of Psychology, University of Kentucky, Lexington, KY 40506-0044, USA |
|
| |
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 |
0376-6357 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15518990 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
227 |
|
| Permanent link to this record |
