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Author Cameron, E.Z.; du Toit, J.T. doi  openurl
  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 (up) 1537-5323 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17206591 Approved no  
  Call Number refbase @ user @ Serial 410  
Permanent link to this record
 

 
Author Nicol, C.J. openurl 
  Title Development, direction, and damage limitation: social learning in domestic fowl Type Journal Article
  Year 2004 Publication Learning & behavior : a Psychonomic Society publication Abbreviated Journal Learn Behav  
  Volume 32 Issue 1 Pages 72-81  
  Keywords Adaptation, Psychological; Age Factors; Animals; Behavior, Animal; *Chickens; *Feeding Behavior; *Food Preferences; *Imitative Behavior; Imprinting (Psychology); *Learning; Maternal Behavior; Reinforcement (Psychology); *Social Environment; *Social Facilitation  
  Abstract This review highlights two areas of particular interest in the study of social learning in fowl. First, the role of social learning in the development of feeding and foraging behavior in young chicks and older birds is described. The role of the hen as a demonstrator and possible teacher is considered, and the subsequent social influence of brood mates and other companions on food avoidance and food preference learning is discussed. Second, the way in which work on domestic fowl has contributed to an understanding of the importance of directed social learning is examined. The well-characterized hierarchical social organization of small chicken flocks has been used to design studies which demonstrate that the probability of social transmission is strongly influenced by social relationships between birds. The practical implications of understanding the role of social learning in the spread of injurious behaviors in this economically important species are briefly considered.  
  Address Department of Clinical Veterinary Science, University of Bristol, Langford, Bristol, England. c.j.nicol@bristol.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 (up) 1543-4494 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15161142 Approved no  
  Call Number refbase @ user @ Serial 75  
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Author Fragaszy, D.; Visalberghi, E. openurl 
  Title Socially biased learning in monkeys Type Journal Article
  Year 2004 Publication Learning & behavior : a Psychonomic Society publication Abbreviated Journal Learn Behav  
  Volume 32 Issue 1 Pages 24-35  
  Keywords Adaptation, Psychological; Animal Communication; Animals; Behavior, Animal; *Feeding Behavior/psychology; Food Preferences/psychology; Haplorhini/*psychology; *Imitative Behavior; Imprinting (Psychology); *Learning; *Social Environment; *Social Facilitation  
  Abstract We review socially biased learning about food and problem solving in monkeys, relying especially on studies with tufted capuchin monkeys (Cebus apella) and callitrichid monkeys. Capuchin monkeys most effectively learn to solve a new problem when they can act jointly with an experienced partner in a socially tolerant setting and when the problem can be solved by direct action on an object or substrate, but they do not learn by imitation. Capuchin monkeys are motivated to eat foods, whether familiar or novel, when they are with others that are eating, regardless of what the others are eating. Thus, social bias in learning about foods is indirect and mediated by facilitation of feeding. In most respects, social biases in learning are similar in capuchins and callitrichids, except that callitrichids provide more specific behavioral cues to others about the availability and palatability of foods. Callitrichids generally are more tolerant toward group members and coordinate their activity in space and time more closely than capuchins do. These characteristics support stronger social biases in learning in callitrichids than in capuchins in some situations. On the other hand, callitrichids' more limited range of manipulative behaviors, greater neophobia, and greater sensitivity to the risk of predation restricts what these monkeys learn in comparison with capuchins. We suggest that socially biased learning is always the collective outcome of interacting physical, social, and individual factors, and that differences across populations and species in social bias in learning reflect variations in all these dimensions. Progress in understanding socially biased learning in nonhuman species will be aided by the development of appropriately detailed models of the richly interconnected processes affecting learning.  
  Address Psychology Department, University of Georgia, Athens, Georgia 30602, USA. doree@uga.edu  
  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 (up) 1543-4494 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15161138 Approved no  
  Call Number refbase @ user @ Serial 828  
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Author Loyola, E.G.; Rodriguez, M.H.; Gonzalez, L.; Arredondo, J.I.; Bown, D.N.; Vaca, M.A. openurl 
  Title Effect of indoor residual spraying of DDT and bendiocarb on the feeding patterns of Anopheles pseudopunctipennis in Mexico Type Journal Article
  Year 1990 Publication Journal of the American Mosquito Control Association Abbreviated Journal J Am Mosq Control Assoc  
  Volume 6 Issue 4 Pages 635-640  
  Keywords Animals; Anopheles/*physiology; *Carbamates; Cattle; *Ddt; Ecology; Enzyme-Linked Immunosorbent Assay; Feeding Behavior/*drug effects; Horses; Humans; Insect Vectors; Insecticide Resistance; *Insecticides; Mexico; *Phenylcarbamates; Seasons  
  Abstract Intense and persistent use of DDT for malaria control has increased resistance and induced exophilic behavior of Anopheles pseudopunctipennis. An evaluation of bendiocarb and DDT to control this species in Sinaloa, Mexico, showed that, in spite of DDT-resistance, both insecticides produced similar effects. Feeding patterns were analyzed to explain these results. Resting mosquitoes were collected over the dry and wet seasons. Anophelines were tested in an ELISA to determine the source of the meals. The human blood index (HBI) ranged from 3.3 to 6.8% in DDT- and from 12.7 to 26.9% in bendiocarb-sprayed houses. Irritability and repellency in DDT-sprayed houses could explain the reduced HBI. In contrast, bendiocarb produced higher mortality. These effects could have affected different components of the vectorial capacity and similarly reduced malaria.  
  Address Center for Malaria Research, Chiapas, Mexico  
  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 (up) 8756-971X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:2098469 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2671  
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