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Author (down) Sivak, J.G.; Allen, D.B. doi  openurl
  Title An evaluation of the “ramp” retina of the horse eye Type Journal Article
  Year 1975 Publication Vision Research Abbreviated Journal Vision Res  
  Volume 15 Issue 12 Pages 1353-1356  
  Keywords Accommodation, Ocular; Animals; Aqueous Humor/physiology; Cornea/physiology; Freezing; Horses/*anatomy & histology; Lens, Crystalline/anatomy & histology/physiology; Refraction, Ocular; Retina/*anatomy & histology; Vitreous Body/physiology  
  Abstract Using a rapid freezing and sectioning technique, the distance between the lens and retina of the horse eye was measured. There is no indication of a ramp retina that could serve accommodation. The pupil axis of the eye coincides with the maximum lens to retina distance. The changes in the lens-retina distance are greater below the axis than above it. Calculations were made of refractive power of the horse eye from measurements of curvature and refractive indices of the ocular tissues. These calculations agree both qualitatively and quantitatively with retinoscopic measurements on live horses. Both show that the refractive state shifts in the direction of hyperopia above and below the axis and that this shift is greater below the axis than above it. Some dynamic accommodative ability in the living eye was observed.  
  Address  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0042-6989 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:1210017 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3647  
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Author (down) Sinha, A. doi  openurl
  Title Knowledge acquired and decisions made: triadic interactions during allogrooming in wild bonnet macaques, Macaca radiata Type Journal Article
  Year 1998 Publication Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences Abbreviated Journal Philos Trans R Soc Lond B Biol Sci  
  Volume 353 Issue 1368 Pages 619-631  
  Keywords Aggression; Animals; Cognition; Computer Simulation; Decision Making; Evolution; Female; Grooming; Logistic Models; Macaca radiata/*psychology; *Social Behavior; Social Dominance  
  Abstract The pressures of developing and maintaining intricate social relationships may have led to the evolution of enhanced cognitive abilities in many nonhuman primates. Knowledge of the dominance ranks and social relationships of other individuals, in particular, is important in evaluating one's position in the rank hierarchy and affiliative networks. Triadic interactions offer an excellent opportunity to examine whether decisions are taken by individuals on the basis of such knowledge. Allogrooming supplants among wild female bonnet macaques (macaca radiata) usually involved the subordinate female of a grooming dyad retreating at the approach of a female dominant to both members of the dyad. In a few exceptional cases, however, the dominant member of the dyad retreated; simple non-cognitive hypotheses involving dyadic rank differences and agonistic relationships failed to explain this phenomenon. Instead, retreat by the dominant individual was positively correlated with the social attractiveness of her subordinate companion (as measured by the duration of grooming received by the latter from other females in the troop). This suggests that not only does an individual evaluate relationships among other females, but does so on the basis of the amount of grooming received by them. Similarly, the frequency of approaches received by any female was correlated with her social attractiveness when she was the dominant member of the dyad, but not when she was the subordinate. This indicated that approaching females might be aware of the relative dominance ranks of the two allogrooming individuals. In logistic regression analyses, the probability of any individual retreating was found to be influenced more by her knowledge of her rank difference with both the other interactants, rather than by their absolute ranks. Moreover, information about social attractiveness appeared to be used in terms of correlated dominance ranks. The nature of knowledge acquired by bonnet macaque females may thus be egotistical in that other individuals are evaluated relative to oneself, integrative in that information about all other interactants is used simultaneously, and hierarchical in the ability to preferentially use certain categories of knowledge for the storage of related information from other domains.  
  Address National Centre for Biological Sciences, TIFR Centre, Bangalore, India  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0962-8436 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:9602536 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4362  
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Author (down) Singer, R.A.; Klein, E.D.; Zentall, T.R. openurl 
  Title Use of a single-code/default strategy by pigeons to acquire duration sample discriminations Type Journal Article
  Year 2006 Publication Learning & behavior : a Psychonomic Society publication Abbreviated Journal Learn Behav  
  Volume 34 Issue 4 Pages 340-347  
  Keywords Animals; Behavior, Animal/*physiology; Columbidae; *Discrimination (Psychology); *Reaction Time; Retention (Psychology); *Signal Detection (Psychology)  
  Abstract Past evidence that pigeons may adopt a single-code/default strategy to solve duration sample discriminations may be attributable to the similarity between the intertrial interval (ITI) and the retention interval. The present experiments tested whether pigeons would adopt a single-code/default strategy when possible ITI-retention-interval ambiguity was eliminated and sample salience was increased. Previous studies of duration sample discriminations that have purported to show evidence for the use of a single-code/default coding strategy have used durations of 0, 2, and 10 sec (Zentall, Klein, and Singer, 2004). However, the results of Experiment 1 suggest that the use of a 0-sec sample may produce an artifact resulting in inadvertent present/absent sample matching. In Experiment 2, when pigeons were trained with three nonzero duration samples (2, 8, and 32 sec), clear evidence for the use of a single-code/default strategy was found.  
  Address Department of Psychology, University of Kentucky, Lexington, KY 40506-0044, USA. rasing2@uky.edu  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1543-4494 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17330523 Approved no  
  Call Number refbase @ user @ Serial 215  
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Author (down) Singer, E.R.; Saxby, F.; French, N.P. openurl 
  Title A retrospective case-control study of horse falls in the sport of horse trials and three-day eventing Type Journal Article
  Year 2003 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 35 Issue 2 Pages 139-145  
  Keywords Accidental Falls/prevention & control/*statistics & numerical data; Adolescent; Adult; Animals; Athletic Injuries/epidemiology/etiology/prevention & control/*veterinary; Case-Control Studies; Child; Confidence Intervals; Female; Horses/*injuries; Humans; Logistic Models; Male; Odds Ratio; Retrospective Studies; Risk Factors; Safety; *Sports/standards  
  Abstract REASONS FOR PERFORMING STUDY: Serious injuries to horses and riders in horse trials (HT) and three-day events (3DE) are usually associated with falls of horses, which invariably involve falls of the riders. Many potential causes for these falls have been discussed. OBJECTIVES: The aim of this case-control study was to investigate the risk factors for horse falls on the cross-country phase of horse trials and three-day events. METHODS: Using retrospective data, significant risk factors identified with unvariable analysis (P value <0.2) were entered into a multivariable logistic regression model. Significant risk factors (P value <0.05) were included in the final model. RESULTS: It was revealed that a number of course, obstacle and rider variables were significantly and independently associated with the risk of falling. Falling was associated with obstacles sited downhill (Odds ratio [OR] 8.41) and with obstacles with ditches in front (OR = 5.77). CONCLUSIONS: The relationship between course variables and the risk of falling was characterised and showed a significantly increased risk with increasing numbers of jumps on the course and for jumping efforts later in the course. In contrast, after allowing for the total number of obstacles on the course, an increase in the total number of jumping efforts appeared to have a protective effect. A later cross-country start time was associated with a decreased risk of a horse fall. Amateur event riders were approximately 20 times more likely to fall than professional riders. POTENTIAL CLINICAL RELEVANCE: This study has identified a number of risk factors associated with horse falls and highlights areas that can be altered to improve safety in cross-country competitions.  
  Address Division of Equine Studies, University of Liverpool, Leahurst, Chester High Road, Neston, South Wirral CH64 7TE, UK  
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  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 PMID:12638789 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3661  
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Author (down) Sinclair, M.; Buhrmann, G.; Gummow, B. openurl 
  Title An epidemiological investigation of the African horsesickness outbreak in the Western Cape Province of South Africa in 2004 and its relevance to the current equine export protocol Type Journal Article
  Year 2006 Publication Journal of the South African Veterinary Association Abbreviated Journal J S Afr Vet Assoc  
  Volume 77 Issue 4 Pages 191-196  
  Keywords African Horse Sickness/diagnosis/*epidemiology; African horse sickness virus/*isolation & purification; Animals; Ceratopogonidae/virology; Diagnosis, Differential; Disease Outbreaks/*veterinary; Female; Horses; Insect Vectors/virology; Male; Prevalence; Retrospective Studies; Sentinel Surveillance; South Africa/epidemiology; Viral Vaccines/administration & dosage  
  Abstract African Horsesickness (AHS) is a controlled disease in South Africa. The country is divided into an infected area and a control area. An outbreak of AHS in the control area can result in a ban of exports for at least 2 years. A retrospective epidemiological study was carried out on data collected during the 2004 AHS outbreak in the surveillance zone of the AHS control area in the Western Cape Province. The objective of this study was to describe the 2004 outbreak and compare it with the 1999 AHS outbreak in the same area. As part of the investigation, a questionnaire survey was conducted in the 30 km radius surrounding the index case. Spatial, temporal and population patterns for the outbreak are described. The investigation found that the outbreak occurred before any significant rainfall and that the main AHS vector (Culicoides imicola) was present in abundance during the outbreak. Furthermore, 63% of cases occurred at temperatures < or = 15 degrees C, the Eerste River Valley was a high risk area, only 17% of owners used vector protection as a control measure and 70% of horses in the outbreak area were protected by means of vaccination at the start of the outbreak. The study revealed that the current AHS control measures do not function optimally because of the high percentage of vaccinated horses in the surveillance zone, which results in insufficient sentinel animals and the consequent failure of the early warning system. Alternative options for control that allow continued export are discussed in the paper.  
  Address State Veterinarian Epidemiology, Elsenburg, South Africa. marnas@elsenburg.com  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1019-9128 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17458343 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2354  
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Author (down) Shultz, S.; Dunbar, R.I.M. url  doi
openurl 
  Title Both social and ecological factors predict ungulate brain size Type Journal Article
  Year 2006 Publication Proceedings. Biological Sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 273 Issue 1583 Pages 207-215  
  Keywords Animals; Artiodactyla/*anatomy & histology/*physiology; Brain/*anatomy & histology/physiology; *Ecosystem; Organ Size; Perissodactyla/*anatomy & histology/*physiology; *Social Behavior  
  Abstract Among mammals, the members of some Orders have relatively large brains. Alternative explanations for this have emphasized either social or ecological selection pressures favouring greater information-processing capacities, including large group size, greater foraging efficiency, higher innovation rates, better invasion success and complex problem solving. However, the focal taxa for these analyses (primates, carnivores and birds) often show both varied ecological competence and social complexity. Here, we focus on the specific relationship between social complexity and brain size in ungulates, a group with relatively simple patterns of resource use, but extremely varied social behaviours. The statistical approach we used, phylogenetic generalized least squares, showed that relative brain size was independently associated with sociality and social complexity as well as with habitat use, while relative neocortex size is associated with social but not ecological factors. A simple index of sociality was a better predictor of both total brain and neocortex size than group size, which may indicate that the cognitive demands of sociality depend on the nature of social relationships as well as the total number of individuals in a group.  
  Address School of Biological Sciences, University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK. susanne.shultz@liv.ac.uk  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16555789 Approved no  
  Call Number Serial 2098  
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Author (down) Shoshani, J.; Kupsky, W.J.; Marchant, G.H. doi  openurl
  Title Elephant brain. Part I: gross morphology, functions, comparative anatomy, and evolution Type Journal Article
  Year 2006 Publication Brain Research Bulletin Abbreviated Journal Brain Res Bull  
  Volume 70 Issue 2 Pages 124-157  
  Keywords Animals; Brain/*anatomy & histology/blood supply/*physiology; Cats; Chinchilla; Elephants/*anatomy & histology/*physiology; Equidae; *Evolution; Female; Guinea Pigs; Haplorhini; Humans; Hyraxes; Male; Pan troglodytes; Sheep; Wolves  
  Abstract We report morphological data on brains of four African, Loxodonta africana, and three Asian elephants, Elephas maximus, and compare findings to literature. Brains exhibit a gyral pattern more complex and with more numerous gyri than in primates, humans included, and in carnivores, but less complex than in cetaceans. Cerebral frontal, parietal, temporal, limbic, and insular lobes are well developed, whereas the occipital lobe is relatively small. The insula is not as opercularized as in man. The temporal lobe is disproportionately large and expands laterally. Humans and elephants have three parallel temporal gyri: superior, middle, and inferior. Hippocampal sizes in elephants and humans are comparable, but proportionally smaller in elephant. A possible carotid rete was observed at the base of the brain. Brain size appears to be related to body size, ecology, sociality, and longevity. Elephant adult brain averages 4783 g, the largest among living and extinct terrestrial mammals; elephant neonate brain averages 50% of its adult brain weight (25% in humans). Cerebellar weight averages 18.6% of brain (1.8 times larger than in humans). During evolution, encephalization quotient has increased by 10-fold (0.2 for extinct Moeritherium, approximately 2.0 for extant elephants). We present 20 figures of the elephant brain, 16 of which contain new material. Similarities between human and elephant brains could be due to convergent evolution; both display mosaic characters and are highly derived mammals. Humans and elephants use and make tools and show a range of complex learning skills and behaviors. In elephants, the large amount of cerebral cortex, especially in the temporal lobe, and the well-developed olfactory system, structures associated with complex learning and behavioral functions in humans, may provide the substrate for such complex skills and behavior.  
  Address Department of Biology, University of Asmara, P.O. Box 1220, Asmara, Eritrea (Horn of Africa). hezy@bio.uoa.edu.er  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0361-9230 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16782503 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2623  
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Author (down) Shettleworth, S.J.; Westwood, R.P. openurl 
  Title Divided attention, memory, and spatial discrimination in food-storing and nonstoring birds, black-capped chickadees (Poecile atricapilla) and dark-eyed juncos (Junco hyemalis) Type Journal Article
  Year 2002 Publication Journal of experimental psychology. Animal behavior processes Abbreviated Journal J Exp Psychol Anim Behav Process  
  Volume 28 Issue 3 Pages 227-241  
  Keywords Animals; Attention/*physiology; Behavior, Animal/physiology; Birds; *Discrimination (Psychology); *Food Habits; Memory/*physiology; Space Perception/*physiology; Spatial Behavior/*physiology  
  Abstract Food-storing birds, black-capped chickadees (Poecile atricapilla), and nonstoring birds, dark-eyed juncos (Junco hyemalis), matched color or location on a touch screen. Both species showed a divided attention effect for color but not for location (Experiment 1). Chickadees performed better on location than on color with retention intervals up to 40 s, but juncos did not (Experiment 2). Increasing sample-distractor distance improved performance similarly in both species. Multidimensional scaling revealed that both use a Euclidean metric of spatial similarity (Experiment 3). When choosing between the location and color of a remembered item, food storers choose location more than do nonstorers. These results explain this effect by differences in memory for location relative to color, not division of attention or spatial discrimination ability.  
  Address Department of Psychology, University of Toronto, 100 Saint George Street, Toronto, Ontario M5S 3G3, Canada. shettle@psych.utoronto.ca  
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  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:12136700 Approved no  
  Call Number refbase @ user @ Serial 370  
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Author (down) Shettleworth, S.J.; Sutton, J.E. doi  openurl
  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  
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  ISSN 0097-7403 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15839771 Approved no  
  Call Number refbase @ user @ Serial 364  
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Author (down) Shettleworth, S.J.; Plowright, C.M. openurl 
  Title How pigeons estimate rates of prey encounter Type Journal Article
  Year 1992 Publication Journal of experimental psychology. Animal behavior processes Abbreviated Journal J Exp Psychol Anim Behav Process  
  Volume 18 Issue 3 Pages 219-235  
  Keywords Analysis of Variance; Animals; *Appetitive Behavior; Columbidae; Conditioning, Operant; Food Preferences/*psychology; Motivation; *Predatory Behavior; *Probability Learning; *Reinforcement Schedule; Social Environment  
  Abstract Pigeons were trained on operant schedules simulating successive encounters with prey items. When items were encountered on variable-interval schedules, birds were more likely to accept a poor item (long delay to food) the longer they had just searched, as if they were averaging prey density over a short memory window (Experiment 1). Responding as if the immediate future would be like the immediate past was reversed when a short search predicted a long search next time (Experiment 2). Experience with different degrees of environmental predictability appeared to change the length of the memory window (Experiment 3). The results may reflect linear waiting (Higa, Wynne, & Staddon, 1991), but they differ in some respects. The findings have implications for possible mechanisms of adjusting behavior to current reinforcement conditions.  
  Address Department of Psychology, University of Toronto, Ontario, Canada  
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  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:1619391 Approved no  
  Call Number refbase @ user @ Serial 382  
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