toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Viscido, S.V.; Miller, M.; Wethey, D.S. doi  openurl
  Title The response of a selfish herd to an attack from outside the group perimeter Type Journal Article
  Year 2001 Publication Journal of theoretical biology Abbreviated Journal J. Theor. Biol.  
  Volume 208 Issue 3 Pages 315-328  
  Keywords Animals; *Behavior, Animal; *Computer Simulation; Models, Biological; *Movement; Predatory Behavior  
  Abstract According to the selfish herd hypothesis, animals can decrease predation risk by moving toward one another if the predator can appear anywhere and will attack the nearest target. Previous studies have shown that aggregations can form using simple movement rules designed to decrease each animal's Domain of Danger. However, if the predator attacks from outside the group's perimeter, these simple movement rules might not lead to aggregation. To test whether simple selfish movement rules would decrease predation risk for those situations when the predator attacks from outside the flock perimeter, we constructed a computer model that allowed flocks of 75 simulated fiddler crabs to react to one another, and to a predator attacking from 7 m away. We attacked simulated crab flocks with predators of different sizes and attack speeds, and computed relative predation risk after 120 time steps. Final trajectories showed flight toward the center of the flock, but curving away from the predator. Path curvature depended on the predator's size and approach speed. The average crab experienced a greater decrease in predation risk when the predator was small or slow moving. Regardless of the predator's size and speed, however, predation risk always decreased as long as crabs took their flock-mates into account. We conclude that, even when flight away from an external predator occurs, the selfish avoidance of danger can lead to aggregation.  
  Address Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, U.S.A. viscido@u.washington.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 0022-5193 ISBN Medium  
  Area Expedition Conference  
  Notes (up) PMID:11207093 Approved no  
  Call Number refbase @ user @ Serial 555  
Permanent link to this record
 

 
Author Virga, V.; Houpt, K.A. openurl 
  Title Prevalence of placentophagia in horses Type Journal Article
  Year 2001 Publication Equine veterinary journal Abbreviated Journal Equine Vet J  
  Volume 33 Issue 2 Pages 208-210  
  Keywords Animals; *Behavior, Animal; Colic/epidemiology/*veterinary; Exploratory Behavior; *Feeding Behavior; Female; Horse Diseases/*epidemiology; Horses; Incidence; New York/epidemiology; *Placenta; Postpartum Period; Pregnancy; Prevalence; Questionnaires  
  Abstract  
  Address Animal Behavior Clinic, Cornell University Hospital for Animals, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, 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 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes (up) PMID:11266073 Approved no  
  Call Number refbase @ user @ Serial 31  
Permanent link to this record
 

 
Author Goodwin, D. openurl 
  Title The importance of ethology in understanding the behaviour of the horse Type Journal Article
  Year 1999 Publication Equine Veterinary Journal. Supplement Abbreviated Journal Equine Vet J Suppl  
  Volume Issue 28 Pages 15-19  
  Keywords *Animal Husbandry; Animals; *Behavior, Animal; Bonding, Human-Pet; Evolution; *Horses; Social Behavior  
  Abstract Domestication has provided the horse with food, shelter, veterinary care and protection, allowing individuals an increased chance of survival. However, the restriction of movement, limited breeding opportunities and a requirement to expend energy, for the benefit of another species, conflict with the evolutionary processes which shaped the behaviour of its predecessors. The behaviour of the horse is defined by its niche as a social prey species but many of the traits which ensured the survival of its ancestors are difficult to accommodate in the domestic environment. There has been a long association between horses and man and many features of equine behaviour suggest a predisposition to interspecific cooperation. However, the importance of dominance in human understanding of social systems has tended to overemphasize its importance in the human-horse relationship. The evolving horse-human relationship from predation to companionship, has resulted in serial conflicts of interest for equine and human participants. Only by understanding the nature and origin of these conflicts can ethologists encourage equine management practices which minimise deleterious effects on the behaviour of the horse.  
  Address Anthrozoology Institute, University of Southampton, Bassett Crescent East, Southampton S016 7PX, 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 ISBN Medium  
  Area Expedition Conference  
  Notes (up) PMID:11314229 Approved no  
  Call Number refbase @ user @ Serial 1920  
Permanent link to this record
 

 
Author Ricard, A.; Chanu, I. doi  openurl
  Title Genetic parameters of eventing horse competition in France Type Journal Article
  Year 2001 Publication Genetics, Selection, Evolution. : GSE Abbreviated Journal Genet Sel Evol  
  Volume 33 Issue 2 Pages 175-190  
  Keywords Animals; Behavior, Animal; Female; France; Genotype; Horses/*genetics; Male; Physical Conditioning, Animal; Selection (Genetics); *Sports; Stereotyped Behavior  
  Abstract Genetic parameters of eventing horse competitions were estimated. About 13 000 horses, 30 000 annual results during 17 years and 110 000 starts in eventing competitions during 8 years were recorded. The measures of performance were logarithmic transformations of annual earnings, annual earnings per start, and annual earnings per place, and underlying variables responsible for ranks in each competition. Heritabilities were low (0.11 / 0.17 for annual results, 0.07 for ranks). Genetic correlations between criteria were high (greater than 0.90) except between ranks and earnings per place (0.58) or per start (0.67). Genetic correlations between ages (from 5 to 10 years old) were also high (more than 0.85) and allow selection on early performances. The genetic correlation between the results in different levels of competition (high/international and low/amateur) was near 1. Genetic correlations of eventing with other disciplines, which included partial aptitude needed for eventing, were very low for steeplechase races (0.18) and moderate with sport: jumping (0.45), dressage (0.58). The results suggest that selection on jumping performance will lead to some positive correlated response for eventing performance, but much more response could be obtained if a specific breeding objective and selection criteria were developed for eventing.  
  Address Institut national de la recherche agronomique, Station de genetique quantitative et appliquee, 78352 Jouy-en-Josas Cedex, France. ugenata@dga.inra.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 0999-193X ISBN Medium  
  Area Expedition Conference  
  Notes (up) PMID:11333833 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3728  
Permanent link to this record
 

 
Author Dorrance, B.R.; Zentall, T.R. openurl 
  Title Imitative learning in Japanese quail (Coturnix japonica) depends on the motivational state of the observer quail at the time of observation Type Journal Article
  Year 2001 Publication Journal of comparative psychology (Washington, D.C. : 1983) Abbreviated Journal J Comp Psychol  
  Volume 115 Issue 1 Pages 62-67  
  Keywords Animals; *Behavior, Animal; *Coturnix; Female; *Imitative Behavior; *Learning; Male; *Motivation; Reinforcement (Psychology); Time Factors  
  Abstract The 2-action method was used to examine whether imitative learning in Japanese quail (Coturnix japonica) depends on the motivational state of the observer quail at the time of observation of the demonstrated behavior. Two groups of observers were fed before observation (satiated groups), whereas 2 other groups of observers were deprived of food before observation (hungry groups). Quail were tested either immediately following observation or after a 30-min delay. Results indicated that quail in the hungry groups imitated, whereas those in the satiated groups did not, regardless of whether their test was immediate or delayed. The results suggest that observer quail may not learn (through observation) behavior that leads to a reinforcer for which they are unmotivated at the time of test. In addition, the results show that quail are able to delay the performance of a response acquired through observation (i.e., they show deferred imitation).  
  Address Department of Psychology, University of Kentucky, Lexington 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 0735-7036 ISBN Medium  
  Area Expedition Conference  
  Notes (up) PMID:11334220 Approved no  
  Call Number refbase @ user @ Serial 245  
Permanent link to this record
 

 
Author Whiten, A.; McGrew, W.C. doi  openurl
  Title Is this the first portrayal of tool use by a chimp? Type
  Year 2001 Publication Nature Abbreviated Journal Nature  
  Volume 409 Issue 6816 Pages 12  
  Keywords Animals; *Behavior, Animal; Pan troglodytes/*physiology; Philately  
  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 0028-0836 ISBN Medium  
  Area Expedition Conference  
  Notes (up) PMID:11343083 Approved no  
  Call Number refbase @ user @ Serial 739  
Permanent link to this record
 

 
Author McGreevy, P.D.; Webster, A.J.; Nicol, C.J. openurl 
  Title Study of the behaviour, digestive efficiency and gut transit times of crib-biting horses Type Journal Article
  Year 2001 Publication The Veterinary record Abbreviated Journal Vet. Rec.  
  Volume 148 Issue 19 Pages 592-596  
  Keywords Animals; Behavior, Animal/*physiology; Case-Control Studies; *Digestion; *Gastrointestinal Motility/drug effects; Horse Diseases/*physiopathology; Horses/*physiology/psychology; Male; Stereotyped Behavior/*physiology; Sulfapyridine/blood; Sulfasalazine/diagnostic use/pharmacology  
  Abstract The spontaneous behaviour and the apparent digestibility of dry matter and fibre and transit times of digesta were compared in four normal horses and four crib-biters. A technique was developed for measuring total gut transit times (TGTT) by using single-stool analysis of the passage of radio-opaque polyethylene markers. Longer TGTT were recorded in the crib-biters than in the normal horses but the orocaecal transit times did not differ. The crib-biters rested less than the normal horses.  
  Address Department of Clinical Veterinary Science, University of Bristol, Langford  
  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 0042-4900 ISBN Medium  
  Area Expedition Conference  
  Notes (up) PMID:11386445 Approved no  
  Call Number refbase @ user @ Serial 86  
Permanent link to this record
 

 
Author Fischer, J.; Cheney, D.L.; Seyfarth, R.M. doi  openurl
  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 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 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes (up) PMID:11413649 Approved no  
  Call Number refbase @ user @ Serial 694  
Permanent link to this record
 

 
Author Soproni, K.; Miklósi, A.; Topál, J.; Csányi, V. url  doi
openurl 
  Title Comprehension of human communicative signs in pet dogs (Canis familiaris) Type Journal Article
  Year 2001 Publication Journal of Comparative Psychology (Washington, D.C. : 1983) Abbreviated Journal J Comp Psychol  
  Volume 115 Issue 2 Pages 122-126  
  Keywords Animals; *Behavior, Animal; Choice Behavior; Dogs/*psychology; Female; Humans; Male; Nonverbal Communication/*psychology; *Recognition (Psychology); *Social Behavior  
  Abstract On the basis of a study by D. J. Povinelli, D. T. Bierschwale, and C. G. Cech (1999), the performance of family dogs (Canis familiaris) was examined in a 2-way food choice task in which 4 types of directional cues were given by the experimenter: pointing and gazing, head-nodding (“at target”), head turning above the correct container (“above target”), and glancing only (“eyes only”). The results showed that the performance of the dogs resembled more closely that of the children in D. J. Povinelli et al.'s study, in contrast to the chimpanzees' performance in the same study. It seems that dogs, like children, interpret the test situation as being a form of communication. The hypothesis is that this similarity is attributable to the social experience and acquired social routines in dogs because they spend more time in close contact with humans than apes do, and as a result dogs are probably more experienced in the recognition of human gestures.  
  Address Department of Ethology, Budapest, Hungary. lavina@ludens.elte.hu  
  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 (up) PMID:11459158 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4963  
Permanent link to this record
 

 
Author Johnstone, R.A. doi  openurl
  Title Eavesdropping and animal conflict Type Journal Article
  Year 2001 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume 98 Issue 16 Pages 9177-9180  
  Keywords *Aggression; Animals; *Behavior, Animal; *Conflict (Psychology); Models, Theoretical  
  Abstract Fights between pairs of animals frequently take place within a wider social context. The displays exchanged during conflict, and the outcome of an encounter, are often detectable by individuals who are not immediately involved. In at least some species, such bystanders are known to eavesdrop on contests between others, and to modify their behavior toward the contestants in response to the observed interaction. Here, I extend Maynard Smith's well known model of animal aggression, the Hawk-Dove game, to incorporate the possibility of eavesdroppers. I show that some eavesdropping is favored whenever the cost of losing an escalated fight exceeds the value of the contested resource, and that its equilibrium frequency is greatest when costs are relatively high. Eavesdropping reduces the risk of escalated conflict relative to that expected by chance, given the level of aggression in the population. However, it also promotes increased aggression, because it enhances the value of victory. The net result is that escalated conflicts are predicted to occur more frequently when eavesdropping is possible.  
  Address Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, United Kingdom. raj1003@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 0027-8424 ISBN Medium  
  Area Expedition Conference  
  Notes (up) PMID:11459936 Approved no  
  Call Number refbase @ user @ Serial 497  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print