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Author Cameron, E.Z. doi  openurl
  Title Facultative adjustment of mammalian sex ratios in support of the Trivers-Willard hypothesis: evidence for a mechanism Type Journal Article
  Year 2004 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 271 Issue (up) 1549 Pages 1723-1728  
  Keywords Age Factors; Animals; Body Constitution; *Evolution; Female; Glucose/metabolism/physiology; Litter Size; Male; Mammals/*physiology; *Models, Biological; Reproduction/physiology; Seasons; Sex Factors; *Sex Ratio; Time Factors  
  Abstract Evolutionary theory predicts that mothers of different condition should adjust the birth sex ratio of their offspring in relation to future reproductive benefits. Published studies addressing variation in mammalian sex ratios have produced surprisingly contradictory results. Explaining the source of such variation has been a challenge for sex-ratio theory, not least because no mechanism for sex-ratio adjustment is known. I conducted a meta-analysis of previous mammalian sex-ratio studies to determine if there are any overall patterns in sex-ratio variation. The contradictory nature of previous results was confirmed. However, studies that investigated indices of condition around conception show almost unanimous support for the prediction that mothers in good condition bias their litters towards sons. Recent research on the role of glucose in reproductive functioning have shown that excess glucose favours the development of male blastocysts, providing a potential mechanism for sex-ratio variation in relation to maternal condition around conception. Furthermore, many of the conflicting results from studies on sex-ratio adjustment would be explained if glucose levels in utero during early cell division contributed to the determination of offspring sex ratios.  
  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 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15306293 Approved no  
  Call Number refbase @ user @ Serial 413  
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Author Flack, J.C.; Krakauer, D.C.; de Waal, F.B.M. doi  openurl
  Title Robustness mechanisms in primate societies: a perturbation study Type Journal Article
  Year 2005 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 272 Issue (up) 1568 Pages 1091-1099  
  Keywords Aggression/physiology; Animals; *Conflict (Psychology); Female; *Hierarchy, Social; Macaca nemestrina/*physiology; Male; *Models, Theoretical; Observation; *Social Behavior  
  Abstract Conflict management mechanisms have a direct, critical effect on system robustness because they mitigate conflict intensity and help repair damaged relationships. However, robustness mechanisms can also have indirect effects on system integrity by facilitating interactions among components. We explore the indirect role that conflict management mechanisms play in the maintenance of social system robustness, using a perturbation technique to 'knockout' components responsible for effective conflict management. We explore the effects of knockout on pigtailed macaque (Macaca nemestrina) social organization, using a captive group of 84 individuals. This system is ideal in addressing this question because there is heterogeneity in performance of conflict management. Consequently, conflict managers can be easily removed without disrupting other control structures. We find that powerful conflict managers are essential in maintaining social order for the benefit of all members of society. We show that knockout of components responsible for conflict management results in system destabilization by significantly increasing mean levels of conflict and aggression, decreasing socio-positive interaction and decreasing the operation of repair mechanisms.  
  Address Santa Fe Institute, NM 87501, USA. jflack@santafe.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 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16024369 Approved no  
  Call Number refbase @ user @ Serial 165  
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Author Nocera, J.J.; Forbes, G.J.; Giraldeau, L.-A. doi  openurl
  Title Inadvertent social information in breeding site selection of natal dispersing birds Type Journal Article
  Year 2006 Publication Proceedings. Biological Sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 273 Issue (up) 1584 Pages 349-355  
  Keywords Animals; *Behavior, Animal; *Breeding; *Environment; Female; Logistic Models; Male; Songbirds/growth & development/*physiology  
  Abstract Several species use the number of young produced as public information (PI) to assess breeding site quality. PI is inaccessible for synchronously breeding birds because nests are empty by the time the young can collect this information. We investigate if location cues are the next best source of inadvertent social information (ISI) used by young prospectors during breeding site choice. We experimentally deployed ISI as decoys and song playbacks of breeding males in suitable and sub-optimal habitats during pre- and post-breeding periods, and monitored territory establishment during the subsequent breeding season for a social, bobolink (Dolichonyx oryzivorus), and a more solitary species, Nelson's sharp-tailed sparrow (Ammodramus nelsoni). The sparrows did not respond to treatments, but bobolinks responded strongly to post-breeding location cues, irrespective of habitat quality. The following year, 17/20 sub-optimal plots to which bobolink males were recruited were defended for at least two weeks, indicating that song heard the previous year could exert a “carry-over attraction” effect on conspecifics the following year. Sixteen recruited males were natal dispersers, as expected when animals have little opportunity to directly sample their natal habitat quality. We suggest that differences in breeding synchronicity may induce an equivalent clinal distribution of ISI use.  
  Address Department of Biology, University of New Brunswick, Bag Service #45111, Fredericton, NB E3B 6E1, Canada. j.nocera@unb.ca  
  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 PMID:16543178 Approved no  
  Call Number Serial 2129  
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Author Wich, S.A.; de Vries, H. doi  openurl
  Title Male monkeys remember which group members have given alarm calls Type Journal Article
  Year 2006 Publication Proceedings. Biological Sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 273 Issue (up) 1587 Pages 735-740  
  Keywords Animals; Behavior, Animal/*physiology; Cercopithecidae/*physiology/*psychology; Cognition/physiology; Fear/physiology/*psychology; Female; Indonesia; Male; Vocalization, Animal/*physiology  
  Abstract Primates give alarm calls in response to the presence of predators. In some species, such as the Thomas langur (Presbytis thomasi), males only emit alarm calls if there is an audience. An unanswered question is whether the audience's behaviour influences how long the male will continue his alarm calling. We tested three hypotheses that might explain the alarm calling duration of male Thomas langurs: the fatigue, group size and group member behaviour hypotheses. Fatigue and group size did not influence male alarm calling duration. We found that males only ceased calling shortly after all individuals in his group had given at least one alarm call. This shows that males keep track of and thus remember which group members have called.  
  Address Behavioural Biology, Utrecht University, Padualaan 14, 3584 Utrecht, The Netherlands. s.a.wich@bio.uu.nl  
  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 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16608694 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2816  
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Author Wilkins, L.J.; Brown, S.N.; Zimmerman, P.H.; Leeb, C.; Nicol, C.J. openurl 
  Title Investigation of palpation as a method for determining the prevalence of keel and furculum damage in laying hens Type Journal Article
  Year 2004 Publication The Veterinary record Abbreviated Journal Vet. Rec.  
  Volume 155 Issue (up) 18 Pages 547-549  
  Keywords Animal Husbandry/methods; Animal Welfare; Animals; Bone and Bones/*injuries; Chickens/*injuries; Female; Fractures, Bone/diagnosis/epidemiology/*veterinary; Great Britain/epidemiology; Housing, Animal/standards; Oviposition; Palpation/methods/*veterinary; Poultry Diseases/*diagnosis/epidemiology; Prevalence; Sensitivity and Specificity  
  Abstract Old breaks of the keel and furculum were identified by palpation in 500 end-of-lay hens from 10 flocks housed in free-range and barn systems, and the results were compared with the results obtained by a full dissection and inspection. The method was considered to be sufficiently precise to be used as a diagnostic tool although people using it would need to be trained. The results obtained by dissection indicated that 50 to 78 per cent of the birds in the flocks had breaks of the furculum and keel, but no other breaks of bones were detected.  
  Address Department of Clinical Veterinary Science, University of Bristol, Bristol BS40 5DU  
  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 0042-4900 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15559420 Approved no  
  Call Number refbase @ user @ Serial 70  
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Author Paukner, A.; Anderson, J.R.; Fujita, K. doi  openurl
  Title Redundant food searches by capuchin monkeys (Cebus apella): a failure of metacognition? Type Journal Article
  Year 2006 Publication Animal cognition Abbreviated Journal Anim. Cogn.  
  Volume 9 Issue (up) 2 Pages 110-117  
  Keywords Animals; *Appetitive Behavior; Cebus; *Concept Formation; Female; Male; Pattern Recognition, Visual; *Problem Solving; *Visual Perception  
  Abstract This study investigated capuchin monkeys' understanding of their own visual search behavior as a means to gather information. Five monkeys were presented with three tubes that could be visually searched to determine the location of a bait. The bait's visibility was experimentally manipulated, and the monkeys' spontaneous visual searches before tube selection were analyzed. In Experiment 1, three monkeys selected the baited tube significantly above chance; however, the monkeys also searched transparent tubes. In Experiment 2, a bent tube in which food was never visible was introduced. When the bent tube was baited, the monkeys failed to deduce the bait location and responded randomly. They also continued to look into the bent tube despite not gaining any pertinent information from it. The capuchin monkeys' behavior contrasts with the efficient employment of visual search behavior reported in humans, apes and macaques. This difference is consistent with species-related variations in metacognitive abilities, although other explanations are also possible.  
  Address Department of Psychology, University of Stirling, Stirling, FK9 4LA, UK. ap14@stir.ac.uk  
  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 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16184375 Approved no  
  Call Number Admin @ knut @ Serial 15  
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Author Palmer, M.E.; Calve, M.R.; Adamo, S.A. doi  openurl
  Title Response of female cuttlefish Sepia officinalis (Cephalopoda) to mirrors and conspecifics: evidence for signaling in female cuttlefish Type Journal Article
  Year 2006 Publication Animal cognition Abbreviated Journal Anim. Cogn.  
  Volume 9 Issue (up) 2 Pages 151-155  
  Keywords Analysis of Variance; *Animal Communication; Animals; Bias (Epidemiology); Female; Male; Pigmentation/*physiology; Recognition (Psychology)/*physiology; Sepia/*physiology; Visual Perception/*physiology  
  Abstract Cuttlefish have a large repertoire of body patterns that are used for camouflage and interspecific signaling. Intraspecific signaling by male cuttlefish has been well documented but studies on signaling by females are lacking. We found that females displayed a newly described body pattern termed Splotch toward their mirror image and female conspecifics, but not to males, prey or inanimate objects. Female cuttlefish may use the Splotch body pattern as an intraspecific signal, possibly to reduce agonistic interactions. The ability of females to produce a consistent body pattern in response to conspecifics and mirrors suggests that they can recognize same-sex conspecifics using visual cues, despite the lack of sexual dimorphism visible to human observers.  
  Address Dorset Environmental Science Centre, Dorset, ON, Canada, P0A 1E0  
  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 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16408230 Approved no  
  Call Number Admin @ knut @ Serial 16  
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Author Herrmann, E.; Melis, A.P.; Tomasello, M. doi  openurl
  Title Apes' use of iconic cues in the object-choice task Type Journal Article
  Year 2006 Publication Animal cognition Abbreviated Journal Anim. Cogn.  
  Volume 9 Issue (up) 2 Pages 118-130  
  Keywords Animal Communication; Animals; *Appetitive Behavior; *Choice Behavior; *Cues; Female; Gorilla gorilla; Male; *Nonverbal Communication; Pan paniscus; Pan troglodytes; Pongo pygmaeus; *Problem Solving; Space Perception; Species Specificity; Statistics, Nonparametric  
  Abstract In previous studies great apes have shown little ability to locate hidden food using a physical marker placed by a human directly on the target location. In this study, we hypothesized that the perceptual similarity between an iconic cue and the hidden reward (baited container) would help apes to infer the location of the food. In the first two experiments, we found that if an iconic cue is given in addition to a spatial/indexical cue – e.g., picture or replica of a banana placed on the target location – apes (chimpanzees, bonobos, orangutans, gorillas) as a group performed above chance. However, we also found in two further experiments that when iconic cues were given on their own without spatial/indexical information (iconic cue held up by human with no diagnostic spatial/indexical information), the apes were back to chance performance. Our overall conclusion is that although iconic information helps apes in the process of searching hidden food, the poor performance found in the last two experiments is due to apes' lack of understanding of the informative (cooperative) communicative intention of the experimenter.  
  Address Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany. eherrman@eva.mpg.de  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16395566 Approved no  
  Call Number Serial 14  
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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 (up) 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  
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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:11266073 Approved no  
  Call Number refbase @ user @ Serial 31  
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Author Nicol, C.J.; Brown, S.N.; Glen, E.; Pope, S.J.; Short, F.J.; Warriss, P.D.; Zimmerman, P.H.; Wilkins, L.J. doi  openurl
  Title Effects of stocking density, flock size and management on the welfare of laying hens in single-tier aviaries Type Journal Article
  Year 2006 Publication British poultry science Abbreviated Journal Br Poult Sci  
  Volume 47 Issue (up) 2 Pages 135-146  
  Keywords Animal Husbandry/*methods; *Animal Welfare; Animals; Body Constitution/*physiology; Chickens/*physiology; Crowding; Feathers; Female; *Housing, Animal/standards; Mortality; Organ Size; Oviposition/physiology; Population Density; Population Dynamics; Random Allocation  
  Abstract Management practices, stocking rate and flock size may affect laying hen welfare but there have been few replicated studies in commercial non-cage systems that investigate this. This study used a broad range of physical and physiological indicators to assess the welfare of hens in 36 commercial flocks. Six laying period treatments were examined with each treatment replicated 6 times. It was not possible to randomly allocate treatments to houses, so treatment and house were largely confounded. Three stocking rates were compared: 7 birds/m(2) (n = 2450), 9 birds/m(2) (n = 3150) and 12 birds/m(2) in either small (n = 2450) or large (n = 4200) flocks. In addition, at 12 birds/m(2), in both small and large flocks, birds were subjected to either standard (SM) or modified (MM) management. MM flocks had nipple drinkers and no nest-box lights. Bone strength, fracture incidence, heterophil:lymphocyte (H:L) ratio, live weight, organ weights, serum creatine, serum osmolality, muscle pH and faecal corticosterone were measured on samples of birds at the end of the rearing period and at the end of lay. During the laying period, mortality, production and integument condition were recorded at regular intervals. Birds housed at 9 birds/m(2) had higher mortality than birds housed at 12 birds/m(2) by the end of lay, but not higher than birds housed at 7 birds/m(2). Birds housed at 7 and 9 birds/m(2) had lower percent liver weight, and worse plumage condition than most of the 12 bird/m(2) treatments. Modified management tended to improve plumage condition. There were no clear effects of flock size on the welfare indicators recorded. At the end of the rearing period fracture incidence was almost negligible and H:L ratio was within a normal range. By the end of lay fracture incidence was 60% and H:L ratio was high, with no treatment effect for either measure. This, together with information on faecal corticosterone, feather loss and mortality, suggests that the welfare of birds in all treatments was relatively poor by the end of lay.  
  Address School of Veterinary Science, University of Bristol, Langford House, Langford BS40 5DU and ADAS Gleadthorpe, Meden Vale, Mansfield, Notts NG20 9PF, England. c.j.nicol@bristol.ac.uk  
  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 0007-1668 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16641024 Approved no  
  Call Number refbase @ user @ Serial 65  
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