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Author (up) Scheffer, M.; van Nes, E.H. doi  openurl
  Title Self-organized similarity, the evolutionary emergence of groups of similar species Type Journal Article
  Year 2006 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume 103 Issue 16 Pages 6230-6235  
  Keywords Animals; *Competitive Behavior; *Ecosystem; *Evolution; *Models, Biological  
  Abstract Ecologists have long been puzzled by the fact that there are so many similar species in nature. Here we show that self-organized clusters of look-a-likes may emerge spontaneously from coevolution of competitors. The explanation is that there are two alternative ways to survive together: being sufficiently different or being sufficiently similar. Using a model based on classical competition theory, we demonstrate a tendency for evolutionary emergence of regularly spaced lumps of similar species along a niche axis. Indeed, such lumpy patterns are commonly observed in size distributions of organisms ranging from algae, zooplankton, and beetles to birds and mammals, and could not be well explained by earlier theory. Our results suggest that these patterns may represent self-constructed niches emerging from competitive interactions. A corollary of our findings is that, whereas in species-poor communities sympatric speciation and invasion of open niches is possible, species-saturated communities may be characterized by convergent evolution and invasion by look-a-likes.  
  Address Aquatic Ecology and Water Quality Management Group, Department of Environmental Sciences, Wageningen University, P.O. Box 8080, 6700 DD, Wageningen, The Netherlands. marten.scheffer@wur.nl  
  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 PMID:16585519 Approved no  
  Call Number refbase @ user @ Serial 510  
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Author (up) Scheidhacker, M.; Bender, W.; Vaitl, P. url  openurl
  Title Die Wirksamkeit des therapeutischen Reitens bei der Behandlung chronisch schizophrener Patienten Type Journal Article
  Year 1991 Publication Der Nervenarzt Abbreviated Journal Nervenarzt  
  Volume 62 Issue 5 Pages 283-287  
  Keywords Adaptation, Psychological; Adult; Animals; Attention; Chronic Disease; Female; Follow-Up Studies; *Horses; Humans; Male; Psychiatric Status Rating Scales; Psychotherapy/*methods; Schizophrenia/*rehabilitation; *Schizophrenic Psychology; Self Concept; *Sports  
  Abstract After describing horse-riding as a facility in managing mentally ill patients, a program for chronic schizophrenic in-patients is presented. Clinical experience with this program and also results of a controlled study are reported. The therapeutic value and slope for horse-riding are discussed in relation to different diagnoses.  
  Address Bezirkskrankenhaus Haar b. Munchen  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language German Summary Language Original Title Die Wirksamkeit des therapeutischen Reitens bei der Behandlung chronisch schizophrener Patienten. Experimentelle Ergebnisse und klinische Erfahrungen  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-2804 ISBN Medium  
  Area Expedition Conference  
  Notes [The effectiveness of therapeutic horseback-riding in the treatment of chronic schizophrenic patients. Experimental results and clinical experiences] Approved no  
  Call Number Equine Behaviour @ team @ Serial 5067  
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Author (up) Seyfarth, R.M. url  doi
openurl 
  Title A model of social grooming among adult female monkeys Type Journal Article
  Year 1977 Publication Journal of Theoretical Biology Abbreviated Journal J. Theor. Biol.  
  Volume 65 Issue 4 Pages 671-698  
  Keywords Animals; Behavior, Animal; Female; *Grooming; Haplorhini/*physiology; *Models, Biological; Reproduction; Social Dominance; Time Factors  
  Abstract Grooming networks among adult female monkeys exhibit two similar features across a number of different species. High-ranking animals receive more grooming than others, and the majority of grooming occurs between females of adjacent rank. A theoretical model which duplicates these features is presented, and the properties of the model are used to explain the possible causation and function of female grooming behaviour. The model illustrates how relatively simple principles governing the behaviour of individuals may be used to explain more complex aspects of the social structure of non-human primate groups.  
  Address  
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  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 PMID:406485 Approved no  
  Call Number Equine Behaviour @ team @ Serial 5259  
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Author (up) Seyfarth, R.M.; Cheney, D.L. openurl 
  Title Cognitive strategies and the representation of social relations by monkeys Type Journal Article
  Year 2001 Publication Nebraska Symposium on Motivation. Nebraska Symposium on Motivation Abbreviated Journal Nebr Symp Motiv  
  Volume 47 Issue Pages 145-177  
  Keywords Adaptation, Biological; Animals; *Evolution; Family; Female; Haplorhini; Male; Memory; Primates; *Selection (Genetics); *Social Behavior; Social Dominance; *Social Perception  
  Abstract  
  Address University of Pennsylvania, USA  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0146-7875 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11759347 Approved no  
  Call Number refbase @ user @ Serial 345  
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Author (up) Seyfarth, R.M.; Cheney, D.L.; Bergman, T.J. doi  openurl
  Title Primate social cognition and the origins of language Type Journal Article
  Year 2005 Publication Trends in Cognitive Sciences Abbreviated Journal Trends. Cognit. Sci.  
  Volume 9 Issue 6 Pages 264-266  
  Keywords Animals; *Cognition; Humans; *Language; Papio; Psychological Theory; Social Behavior; *Social Perception  
  Abstract Are the cognitive mechanisms underlying language unique, or can similar mechanisms be found in other domains? Recent field experiments demonstrate that baboons' knowledge of their companions' social relationships is based on discrete-valued traits (identity, rank, kinship) that are combined to create a representation of social relations that is hierarchically structured, open-ended, rule-governed, and independent of sensory modality. The mechanisms underlying language might have evolved from the social knowledge of our pre-linguistic primate ancestors.  
  Address Departments of Biology and Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA. seyfarth@psych.upenn.edu  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1364-6613 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15925802 Approved no  
  Call Number refbase @ user @ Serial 343  
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Author (up) 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  
  Corporate Author Thesis  
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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:15839771 Approved no  
  Call Number refbase @ user @ Serial 364  
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Author (up) Skov-Rackette, S.I.; Shettleworth, S.J. doi  openurl
  Title What do rats learn about the geometry of object arrays? Tests with exploratory behavior 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 142-154  
  Keywords Animals; Behavior, Animal; *Discrimination Learning; *Exploratory Behavior; Female; *Form Perception; Habituation, Psychophysiologic; Male; Rats; Rats, Long-Evans  
  Abstract Six experiments using habituation of exploratory behavior tested whether disoriented rats foraging in a large arena encode the shapes of arrays of objects. Rats did not respond to changes in position of a single object, but they responded to a change in object color and to a change in position of 1 object in a square array, as in previous research (e.g., C. Thinus-Blanc et al., 1987). Rats also responded to an expansion of a square array, suggesting that they encoded sets of interobject distances rather than overall shape. In Experiments 4-6, rats did not respond to changes in sense of a triangular array that maintained interobject distances and angles. Shapes of object arrays are encoded differently from shapes of enclosures.  
  Address Department of Psychology, University of Toronto, Toronto, ON M5S 3G3, Canada. shannon.skov.rackette@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:15839772 Approved no  
  Call Number refbase @ user @ Serial 363  
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Author (up) Sloet van Oldruitenborgh-Oosterbaan, M.M.; Blok, M.B.; Begeman, L.; Kamphuis, M.C.D.; Lameris, M.C.; Spierenburg, A.J.; Lashley, M.J.J.O. url  openurl
  Title Workload and stress in horses: comparison in horses ridden deep and round ('rollkur') with a draw rein and horses ridden in a natural frame with only light rein contact Type Journal Article
  Year 2006 Publication Tijdschrift Voor Diergeneeskunde Abbreviated Journal Tijdschr Diergeneeskd  
  Volume 131 Issue 5 Pages 152-157  
  Keywords Animal Husbandry/methods; Animals; Biomechanics; Blood Glucose/analysis; Female; Heart Rate/physiology; Hematocrit/veterinary; Horses/blood/*physiology; Hydrocortisone/blood; Lactic Acid/blood; Physical Conditioning, Animal/adverse effects/*physiology; Stress, Physiological/blood/etiology/veterinary  
  Abstract 'Rollkur' or 'overbending' is the low and deep riding of a dressage horse during training or warming up. Lately, this technique has been criticized, and not necessarily objectively, on welfare grounds. To be able to evaluate these criticisms, more needs to be known about the workload and stress of horses being ridden 'rollkur'. The aim of the present study was to compare the workload of eight riding-school horses when being ridden deep and round with a draw rein ('rollkur') and when being ridden in a natural frame with only light rein contact ('free'). Workload (as measured by heart rate and blood lactate concentration) was slightly higher when horses were ridden 'rollkur' than when they were ridden 'free'. There were no differences in packed cell volume, or glucose and cortisol concentrations. No signs of uneasiness or stress could be determined when the horses were ridden 'rollkur'. Subjectively, all horses improved their way of moving during 'rollkur' and were more responsive to their rider.  
  Address Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 12, 3584 CM Utrecht, The Netherlands. m.sloet@vet.uu.nl  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0040-7453 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16532786 Approved no  
  Call Number Equine Behaviour @ team @ Serial 5638  
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Author (up) Smith, J.E.; Kolowski, J.M.; Graham, K.E.; Dawes, S.E.; Holekamp, K.E. url  doi
openurl 
  Title Social and ecological determinants of fission-fusion dynamics in the spotted hyaena Type Journal Article
  Year 2008 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.  
  Volume 76 Issue 3 Pages 619-636  
  Keywords competition; conflict resolution; cooperative hunting; Crocuta crocuta; ecological constraints; group living; social rank  
  Abstract Theory predicts that individuals living in fission-fusion societies, in which group members frequently change subgroups, should modify grouping patterns in response to varying social and environmental conditions. Spotted hyaenas, Crocuta crocuta, are long-lived carnivores that reside in permanent social groups called clans. Clans are complex, fission-fusion societies in which individual members travel, rest and forage in subgroups that frequently change composition. We studied two clans in Kenya to provide the first detailed description of fission-fusion dynamics in this species. Because social and ecological circumstances can influence the cohesiveness of animal societies, we evaluated the extent to which specific circumstances promote the formation of subgroups of various sizes. We found that cooperative defence of shared resources during interclan competition and protection from lions were cohesive forces that promoted formation of large subgroups. We also tested hypotheses suggesting factors limiting subgroup size. Mothers with small cubs avoided conspecifics, thereby reducing infanticide risk. Victims of aggression either reconciled fights or separated from former opponents to reduce the immediate costs of escalated aggression in the absence of food. As predicted by the ecological constraints hypothesis, hyaenas adjusted their grouping patterns over both short and long time scales in response to feeding competition. Crocuta were most gregarious during periods of abundant prey, joined clanmates at ephemeral kills in numbers that correlated with the energetic value of the prey and gained the most energy when foraging alone because cooperative hunting attracted numerous competitors. Overall, our findings indicate that resource limitation constrains grouping in this species.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 4676  
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Author (up) Smith, L.A.; Wells, K.L.; Marion, G.; Swain, D.L.; Hutchings, M.R. url  doi
openurl 
  Title Effects of group composition on the grazing behaviour of herbivores Type Journal Article
  Year Publication Animal Behaviour. Abbreviated Journal Anim. Behav.  
  Volume In Press, Corrected Proof Issue Pages  
  Keywords grazing; group composition; herbivore; individual behaviour; physiological state  
  Abstract Animal behaviour is often a function of the animal's physiological state. Groups of animals will often contain individuals with a range of physiological states and the grazing behaviour of herbivores is affected by their physiological state. This study compared the grazing decisions of animals in groups of single and mixed physiological states. Using a grazing model that simulated individual herbivore behaviour in relation to environmental distributions of forage resource (grass) and parasites (faeces), we tested the hypothesis that an animal's level of parasite exposure via the faecal-oral route is affected by the composition of physiological states in the group. Four physiological states were considered: parasite-naïve, parasitized, lactating and parasite-immune animals. Baseline parasite exposure levels for each state were generated by simulating single-state groups and were compared to simulations of each of the six two-state combinations. In single-state groups parasitized animals had the least and lactating animals had the greatest levels of parasite exposure. When co-grazing with lactating animals, parasitized, immune and naïve animals increased their parasite exposure, relative to single-state groups. When co-grazing with parasitized animals, lactating, immune and naïve animals reduced their parasite exposure, relative to single-state groups. There was no difference in parasite exposure of the immune or naïve animals co-grazing together when compared to the single-state groups. These results highlight the need to recognize the impact of the individual when studying group-living animals.  
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  Series Volume Series Issue Edition  
  ISSN 0003-3472 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5155  
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