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Author Labruna, M.B.; Amaku, M. doi  openurl
  Title Rhythm of engorgement and detachment of Anocentor nitens females feeding on horses Type Journal Article
  Year 2006 Publication Veterinary Parasitology Abbreviated Journal Vet Parasitol  
  Volume (up) 137 Issue 3-4 Pages 316-332  
  Keywords Animals; Bites and Stings; Feeding Behavior; Female; Horses/*parasitology; Ixodidae/*physiology; Seasons; Tick Infestations/parasitology/*veterinary; Time Factors  
  Abstract The present study evaluated the engorgement and drop-off rhythms of Anocentor nitens females feeding on horses. Drop-off rhythm was evaluated at 6h-intervals (06:00, 12:00, 18:00, and 00:00 h) on horses held in stalls or in a pasture. A new method of marking feeding female ticks (the bowknot technique) was developed to evaluate ticks on horses in pasture that attached to different parts of the horse's body. This technique was highly successful, indicating no significant interference on tick engorgement rate or final tick weight, length and reproductive capability. Horses held in the pasture during the summer produced only 28.2% of the tick detachment during the daylight period from 06:00 to 18:00 h. In contrast, 53.4% of the ticks detached during this same 12 h-period during the winter. This difference was probably related to the longer scotoperiod during the winter. Different drop-off rhythms were observed for females attached to different anatomical parts of the horse's body. For example, ticks attached to the ears, perineum, and tail showed similar drop-off patterns, but were different from ticks attached to mane, rump and other body parts. The idiosoma length of the feeding female ticks was individually measured every 6 h until the engorged female detached naturally. The engorgement rate (increase in millimeters of the body length per hour) was evaluated during the last 96 h of parasitism. The highest engorgement rates were observed during the last 24 h of parasitism (approximately 0.16 mm/h), which were four-fold higher than the engorgement rates of the previous 3 days ( approximately 0.04 mm/h), demonstrating that these lower and higher values corresponded to the slow and rapid feeding phases reported elsewhere. Based on these data, the 6 mm idiosoma length was estimated as the minimal length that would correspond to the time point (i.e. 24 h before detachment) during which ticks would undergo the rapid feeding phase and detach as fully engorged females. When this 6 mm length was tested to estimate the number of engorged females detaching from horses in a period of 24 h, the estimated accuracy varied from 58.5 to 97.7% (mean: 73.3%).  
  Address Departamento de Medicina Veterinaria Preventiva e Saude Animal, Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, Av. Prof. Orlando Marques de Paiva, 87, Cidade Universitaria, Sao Paulo, SP 05508-000, Brazil. labruna@usp.br  
  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 0304-4017 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16481114 Approved no  
  Call Number Serial 1877  
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Author Gauvin, S.; Giraldeau, L.-A. doi  openurl
  Title Nutmeg mannikins ( Lonchura punctulata) reduce their feeding rates in response to simulated competition Type Journal Article
  Year 2004 Publication Oecologia Abbreviated Journal Oecologia  
  Volume (up) 139 Issue 1 Pages 150-156  
  Keywords Animals; *Feeding Behavior; Population Density; *Social Behavior; *Songbirds  
  Abstract Group feeding animals experience a number of competitive foraging costs that may result in a lowered feeding rate. It is important to distinguish between reductions in feeding rates that are caused by reduced food availability and physical interactions among foragers from those caused by the mere presence of foraging companions that may be self-imposed in order to obtain some benefit of group membership. Starlings ( Sturnus vulgaris) reduce their feeding rates when in the company of simulated competitors located in an adjacent cage that cannot affect the food availability or interact with the forager. In the present study, we investigate whether the presence of simulated competitors in another species of passerine, nutmeg mannikins ( Lonchura punctulata), can result in self-imposed reductions in feeding rates. When feeding in the company of simulated competitors, mannikins spent more non-foraging time near them, fed more slowly, reduced travel times between patches, reduced their scanning time and pecked more slowly. These results provide evidence that simulated competitors induce a reduction in pecking rate: behavioural interference. These self-imposed responses to competitors may have resulted from attempts to remain close to the non-feeding companions. Such self-imposed reductions in feeding rates may be a widespread yet generally unrecognised foraging cost to group feeding individuals.  
  Address Department of Biology, Concordia University, Montreal, Quebec, Canada  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0029-8549 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:14722748 Approved no  
  Call Number Serial 2133  
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Author Dubois, F.; Giraldeau, L.-A. openurl 
  Title The forager's dilemma: food sharing and food defense as risk-sensitive foraging options Type Journal Article
  Year 2003 Publication The American Naturalist Abbreviated Journal Am Nat  
  Volume (up) 162 Issue 6 Pages 768-779  
  Keywords Animals; Competitive Behavior/*physiology; *Environment; Feeding Behavior/*physiology; *Game Theory; *Models, Biological; Population Density; Population Dynamics  
  Abstract Although many variants of the hawk-dove game predict the frequency at which group foraging animals should compete aggressively, none of them can explain why a large number of group foraging animals share food clumps without any overt aggression. One reason for this shortcoming is that hawk-dove games typically consider only a single contest, while most group foraging situations involve opponents that interact repeatedly over discovered food clumps. The present iterated hawk-dove game predicts that in situations that are analogous to a prisoner's dilemma, animals should share the resources without aggression, provided that the number of simultaneously available food clumps is sufficiently large and the number of competitors is relatively small. However, given that the expected gain of an aggressive animal is more variable than the gain expected by nonaggressive individuals, the predicted effect of the number of food items in a clump-clump richness-depends on whether only the mean or both the mean and variability associated with payoffs are considered. More precisely, the deterministic game predicts that aggression should increase with clump richness, whereas the stochastic risk-sensitive game predicts that the frequency of encounters resulting in aggression should peak at intermediate clump richnesses or decrease with increasing clump richness if animals show sensitivity to the variance or coefficient of variation, respectively.  
  Address Departement des Sciences Biologiques, Universite du Quebec a Montreal, Case postale 8888, Succursale Centre-Ville, Montreal, Quebec H3C 3P8, Canada. fdubois@u-bourgogne.fr  
  Corporate Author Thesis  
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  Series Volume Series Issue Edition  
  ISSN 0003-0147 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:14737714 Approved no  
  Call Number Serial 2132  
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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 (up) 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  
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  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  
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Author Houpt, K.A.; Smith, R. openurl 
  Title Animal behavior case of the month Type Journal Article
  Year 1993 Publication Journal of the American Veterinary Medical Association Abbreviated Journal J Am Vet Med Assoc  
  Volume (up) 203 Issue 3 Pages 377-378  
  Keywords Aggression; Animals; Animals, Zoo/*psychology; *Behavior, Animal; *Feeding Behavior; Female; Horses/*psychology; *Weaning  
  Abstract  
  Address Department of Physiology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853-6401  
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  Series Volume Series Issue Edition  
  ISSN 0003-1488 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8226214 Approved no  
  Call Number refbase @ user @ Serial 37  
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Author Broom, M. openurl 
  Title A unified model of dominance hierarchy formation and maintenance Type Journal Article
  Year 2002 Publication Journal of theoretical biology Abbreviated Journal J. Theor. Biol.  
  Volume (up) 219 Issue 1 Pages 63-72  
  Keywords Animals; *Behavior, Animal; Feeding Behavior; *Models, Psychological; *Social Dominance; Social Environment  
  Abstract In many different species it is common for animals to spend large portions of their lives in groups. Such groups need to divide available resources amongst the individuals they contain and this is often achieved by means of a dominance hierarchy. Sometimes hierarchies are stable over a long period of time and new individuals slot into pre-determined positions, but there are many situations where this is not so and a hierarchy is formed out of a group of individuals meeting for the first time. There are several different models both of the formation of such dominance hierarchies and of already existing hierarchies. These models often treat the two phases as entirely separate, whereas in reality, if there is a genuine formation phase to the hierarchy, behaviour in this phase will be governed by the rewards available, which in turn depends upon how the hierarchy operates once it has been formed. This paper describes a method of unifying models of these two distinct phases, assuming that the hierarchy formed is stable. In particular a framework is introduced which allows a variety of different models of each of the two parts to be used in conjunction with each other, thus enabling a wide range of situations to be modelled. Some examples are given to show how this works in practice.  
  Address Centre for Statistics and Stochastic Modelling, School of Mathematical Sciences, University of Sussex, Falmer, Brighton, BN1 9QH, U.K. m.broom@sussex.ac.uk  
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  Series Volume Series Issue Edition  
  ISSN 0022-5193 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12392975 Approved no  
  Call Number refbase @ user @ Serial 439  
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Author Whiten, A.; Boesch, C. openurl 
  Title The cultures of chimpanzees Type Journal Article
  Year 2001 Publication Scientific American Abbreviated Journal Sci Am  
  Volume (up) 284 Issue 1 Pages 60-67  
  Keywords Animals; *Behavior, Animal; Culture; Feeding Behavior; Grooming; Hominidae; Humans; Pan troglodytes/*physiology  
  Abstract  
  Address University of St. Andrews  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0036-8733 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11132425 Approved no  
  Call Number refbase @ user @ Serial 740  
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Author Clutton-Brock, T.H.; Russell, A.F.; Sharpe, L.L.; Brotherton, P.N.; McIlrath, G.M.; White, S.; Cameron, E.Z. doi  openurl
  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 (up) 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  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0036-8075 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11577235 Approved no  
  Call Number refbase @ user @ Serial 414  
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Author Danchin, E.; Giraldeau, L.-A.; Valone, T.J.; Wagner, R.H. doi  openurl
  Title Public information: from nosy neighbors to cultural evolution Type Journal Article
  Year 2004 Publication Science (New York, N.Y.) Abbreviated Journal Science  
  Volume (up) 305 Issue 5683 Pages 487-491  
  Keywords Animals; *Behavior, Animal; Cues; *Cultural Evolution; *Decision Making; Environment; Evolution; Feeding Behavior; Female; Genes; Humans; Male; Reproduction; Sexual Behavior, Animal  
  Abstract Psychologists, economists, and advertising moguls have long known that human decision-making is strongly influenced by the behavior of others. A rapidly accumulating body of evidence suggests that the same is true in animals. Individuals can use information arising from cues inadvertently produced by the behavior of other individuals with similar requirements. Many of these cues provide public information about the quality of alternatives. The use of public information is taxonomically widespread and can enhance fitness. Public information can lead to cultural evolution, which we suggest may then affect biological evolution.  
  Address U.P.M.C. CNRS-UMR7625, Bat A-7e etage-Case 237, 7 quai Saint Bernard, 75252 Paris Cedex 05, France. edanchin@snv.jussieu.fr  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1095-9203 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15273386 Approved no  
  Call Number Serial 2131  
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Author Macfadden, B.J. doi  openurl
  Title Evolution. Fossil horses--evidence for evolution Type Journal Article
  Year 2005 Publication Science (New York, N.Y.) Abbreviated Journal Science  
  Volume (up) 307 Issue 5716 Pages 1728-1730  
  Keywords Animals; Body Size; DNA, Mitochondrial; Diet; *Equidae/anatomy & histology/classification/genetics; *Evolution; Feeding Behavior; *Fossils; *Horses/anatomy & histology/classification/genetics; Paleodontology; Phylogeny; Time; Tooth/anatomy & histology  
  Abstract  
  Address Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA. bmacfadd@flmnh.ufl.edu  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 1095-9203 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15774746 Approved no  
  Call Number Serial 1892  
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