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Author Conradt, L.; Roper, T.J. url  doi
openurl 
  Title Group decision-making in animals Type Journal Article
  Year 2003 Publication Nature Abbreviated Journal Nature  
  Volume (down) 421 Issue 6919 Pages 155-158  
  Keywords Animals; Behavior, Animal/*physiology; *Decision Making; Democracy; Group Processes; *Models, Biological; Population Density; Social Behavior  
  Abstract Groups of animals often need to make communal decisions, for example about which activities to perform, when to perform them and which direction to travel in; however, little is known about how they do so. Here, we model the fitness consequences of two possible decision-making mechanisms: 'despotism' and 'democracy'. We show that under most conditions, the costs to subordinate group members, and to the group as a whole, are considerably higher for despotic than for democratic decisions. Even when the despot is the most experienced group member, it only pays other members to accept its decision when group size is small and the difference in information is large. Democratic decisions are more beneficial primarily because they tend to produce less extreme decisions, rather than because each individual has an influence on the decision per se. Our model suggests that democracy should be widespread and makes quantitative, testable predictions about group decision-making in non-humans.  
  Address School of Biological Sciences, University of Sussex, Brighton BN1 9QG, UK. l.conradt@sussex.ac.uk  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0028-0836 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12520299 Approved no  
  Call Number Equine Behaviour @ team @ Serial 5136  
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Author Kostova, T.; Carlsen, T.; Kercher, J. url  doi
openurl 
  Title Individual-based spatially-explicit model of an herbivore and its resource: the effect of habitat reduction and fragmentation Type Journal Article
  Year 2004 Publication Comptes Rendus Biologies Abbreviated Journal Compt. Rend. Biol.  
  Volume (down) 327 Issue 3 Pages 261-276  
  Keywords complexity; population dynamics; self-organization; population waves; individual-based models  
  Abstract We present an individual-based, spatially-explicit model of the dynamics of a small mammal and its resource. The life histories of each individual animal are modeled separately. The individuals can have the status of residents or wanderers and belong to behaviorally differing groups of juveniles or adults and males or females. Their territory defending and monogamous behavior is taken into consideration. The resource, green vegetation, grows depending on seasonal climatic characteristics and is diminished due to the herbivore's grazing. Other specifics such as a varying personal energetic level due to feeding and starvation of the individuals, mating preferences, avoidance of competitors, dispersal of juveniles, as a result of site overgrazing, etc., are included in the model. We determined model parameters from real data for the species Microtus ochrogaster (prairie vole). The simulations are done for a case of an enclosed habitat without predators or other species competitors. The goal of the study is to find the relation between size of habitat and population persistence. The experiments with the model show the populations go extinct due to severe overgrazing, but that the length of population persistence depends on the area of the habitat as well as on the presence of fragmentation. Additionally, the total population size of the vole population obtained during the simulations exhibits yearly fluctuations as well as multi-yearly peaks of fluctuations. This dynamics is similar to the one observed in prairie vole field studies. To cite this article: T. Kostova et al., C. R. Biologies 327 (2004).  
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  Notes Approved no  
  Call Number refbase @ user @ Serial 801  
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Author de Waal, F.B.; Aureli, F.; Judge, P.G. openurl 
  Title Coping with crowding Type Journal Article
  Year 2000 Publication Scientific American Abbreviated Journal Sci Am  
  Volume (down) 282 Issue 5 Pages 76-81  
  Keywords *Adaptation, Psychological; Animals; Behavior, Animal; Emotions; Female; Grooming; Homicide; Humans; Macaca mulatta; Male; Pan troglodytes; *Population Density; Primates; Rodentia; Rural Population; Territoriality; Urban Population; Violence  
  Abstract  
  Address Living Links Center, Yerkes Regional Primate Research Center, Atlanta, USA  
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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:11056991 Approved no  
  Call Number refbase @ user @ Serial 184  
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Author Hall, R.A.; Broom, A.K.; Smith, D.W.; Mackenzie, J.S. openurl 
  Title The ecology and epidemiology of Kunjin virus Type Journal Article
  Year 2002 Publication Current Topics in Microbiology and Immunology Abbreviated Journal Curr Top Microbiol Immunol  
  Volume (down) 267 Issue Pages 253-269  
  Keywords Animals; Culicidae/virology; Ecosystem; Horse Diseases/etiology; Horses; Humans; Insect Vectors; Population Surveillance; West Nile Fever/*epidemiology/*etiology/veterinary; West Nile virus/classification/genetics/immunology/*isolation & purification  
  Abstract  
  Address Department of Microbiology and Parasitology, School of Molecular and Microbial Sciences, The University of Queensland, St. Lucia, Queensland 4072, Australia  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0070-217X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12082993 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2642  
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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 (down) 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  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  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 Li, C.; Jiang, Z.; Tang, S.; Zeng, Y. doi  openurl
  Title Influence of enclosure size and animal density on fecal cortisol concentration and aggression in Pere David's deer stags Type Journal Article
  Year 2007 Publication General and Comparative Endocrinology Abbreviated Journal Gen Comp Endocrinol  
  Volume (down) 151 Issue 2 Pages 202-209  
  Keywords *Aggression; Animals; *Deer; *Environment; Feces/*chemistry; Handling (Psychology); Housing, Animal; Hydrocortisone/*analysis; Male; Population Density  
  Abstract We investigated the impact of enclosure size and animal density on behavior and adrenocortical secretion in Pere David's deer in Dafeng Nature Reserve, China. From February 15 to April 16 in 2004, we conducted two experiments. First, we studied maintenance behavior and conflict behavior of Pere David's deer stags in a large enclosure (200 ha) with low animal density (0.66 deer/ha) and a small display pen (0.75 ha) with high animal density (25.33 deer/ha). The maintenance behavior we recorded included standing, locomotion, foraging and rest. During the behavioral observations, we collected fresh voided fecal samples from the stags periodically, and analyzed the fecal cortisol concentrations in those samples using radioimmunoassay technique. Second, we monitored the fecal cortisol concentrations of one group of stags (12 deer lived in an enclosure of 100 ha) before and after transferred into a small pen (0.5 ha). We found that in the first experiment: (1) there were significant differences in standing and rest whereas no significant differences of locomotion and foraging between the free-ranging group and the display group; (2) frequency of conflict behavior in the display group was significantly higher than those in the free-ranging group; and (3) fecal cortisol concentration of the display group (326.17+/-16.98 ng/g dry feces) was significantly higher than that of the free-ranging group (268.98+/-15.21 ng/g dry feces). In the second experiment, there was no significant difference of the fecal cortisol concentrations among sampling days, but the mean fecal cortisol concentration of the day after transferring (337.46+/-17.88 ng/g dry feces) was significantly higher than that of the day before transferring (248.44+/-7.99 ng/g dry feces). Comparison with published findings, our results indicated that enclosure size and animal density affect not only behaviors, but also adrenocortical secretion in Pere David's deer. Small living space with high animal density may impose physiological stress to captive Pere David's deer. Moreover, long-term physiological stress and increase of conflict behavior may subsequently affect survival and reproduction of the deer.  
  Address Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China  
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  Series Volume Series Issue Edition  
  ISSN 0016-6480 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17324429 Approved no  
  Call Number Equine Behaviour @ team @ Serial 5475  
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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 (down) 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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  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 Watson, L.H.; Odendaal, H.E.; Barry, T.J.; Pietersen, J. doi  openurl
  Title Population viability of Cape mountain zebra in Gamka Mountain Nature Reserve, South Africa: the influence of habitat and fire Type Journal Article
  Year 2005 Publication Biological Conservation Abbreviated Journal Biol. Conserva.  
  Volume (down) 122 Issue 2 Pages 173-180  
  Keywords Mountain zebra; Population viability analysis; Habitat suitability; Fire; Conservation management  
  Abstract The small Cape mountain zebra population in Gamka Mountain Nature Reserve represents a third of the entire gene pool of this endangered species and is thus vital for it's conservation. Presently, management of this population is largely hands off, with the belief that it will grow to levels which will allow it to form a source for the mixing of mountain zebra stocks in the future. The growth of this population however, has been slow and we investigated the influence of habitat and fire on this growth. Firstly, we used a diffusion model to perform a population viability analysis. This analysis indicated that the population had a low probability of attaining quasi-extinction in the next 50 years (G = 0.0032). However, our findings indicated that less than 30% of the reserve was suitable for mountain zebra and that the preferred habitat would have to be burnt at unnaturally short intervals to sustain the present growth. We therefore argue that the risk of quasi-extinction to this population is greater than predicted and suggest that management options need to be implemented to reduce this risk. These options include; translocation to another protected area; acquisition of adjacent land; burning preferred habitat at unnaturally short intervals; forming a conservancy with adjacent landowners; leasing cultivated land for pasture. We suggest that only the latter two options are likely to stimulate mountain zebra population growth in the short term and that these should receive immediate attention.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 3547  
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Author Hebenbrock, M.; Due, M.; Holzhausen, H.; Sass, A.; Stadler, P.; Ellendorff, F. openurl 
  Title A new tool to monitor training and performance of sport horses using global positioning system (GPS) with integrated GSM capabilities Type Journal Article
  Year 2005 Publication DTW. Deutsche Tierarztliche Wochenschrift Abbreviated Journal Dtsch Tierarztl Wochenschr  
  Volume (down) 112 Issue 7 Pages 262-265  
  Keywords Animals; Heart Rate; Horses/*physiology; *Physical Conditioning, Animal; Population Surveillance; *Satellite Communications; Telemetry/methods/*veterinary  
  Abstract Global Positioning Systems (GPS) are considered suitable to monitor the position and velocity of horses during cross-country competition or in training. Furthermore, simultaneous recording of life data such as heart rate could be useful to assess the horse's condition during exercise. To test the suitability and reliability of a commercially available GPS system with integrated heart rate recording system and with built in GSM for data transmission, the Fidelak Equipilot Type EP-2003-15/G-2.11 (EP-15/G) was evaluated first for reliability of pulse recording from a pulse generator within the physiological range of horses; furthermore distance, velocity and heart rate recordings were carried out on a standard 1000 m field track with five repetitions. Agreement (% deviation from actually measured distance and from stopwatch-distance based velocity calculations) and variability (Coefficient of Variation for distance, velocity, heart rate) were calculated. From the results it was safe to assume that the heart rate sensor recorded horse heart rates at a high degree of accuracy. Overall distances and velocities are in high agreement with actually measured values. However, overall variability expressed in terms of relative variability (C.V.) is smaller for distance recording (C.V. 0.68%) when compared to velocity (C.V. 1.01%). The system tested is suitable and reliable for simultaneously recording of distance, velocity and heart rates for horses during cross country exercise. GPS-based monitoring of movement along with simultaneous recording of physiological data and the possibility to call upon data will not only be of benefit for training horses or for surveillance during competition, it may also be suitable for distant patient monitoring and in behavioural studies as well as in veterinary medicine in general.  
  Address Institute for Animal Breeding Mariensee, Federal Agricultural Research Centre (FAL), Neustadt, Germany  
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  Series Volume Series Issue Edition  
  ISSN 0341-6593 ISBN Medium  
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  Notes PMID:16124700 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4035  
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Author Lee, R.D. doi  openurl
  Title Rethinking the evolutionary theory of aging: transfers, not births, shape senescence in social species Type Journal Article
  Year 2003 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc Natl Acad Sci U S A  
  Volume (down) 100 Issue 16 Pages 9637-9642  
  Keywords Adaptation, Physiological; *Aging; Animals; *Biological Evolution; Demography; Economics; Environment; Fertility; Humans; Life Expectancy; Longevity; Models, Theoretical; Parturition; Population Dynamics; Population Growth; Reproduction  
  Abstract The classic evolutionary theory of aging explains why mortality rises with age: as individuals grow older, less lifetime fertility remains, so continued survival contributes less to reproductive fitness. However, successful reproduction often involves intergenerational transfers as well as fertility. In the formal theory offered here, age-specific selective pressure on mortality depends on a weighted average of remaining fertility (the classic effect) and remaining intergenerational transfers to be made to others. For species at the optimal quantity-investment tradeoff for offspring, only the transfer effect shapes mortality, explaining postreproductive survival and why juvenile mortality declines with age. It also explains the evolution of lower fertility, longer life, and increased investments in offspring.  
  Address Department of Demography, University of California, 2232 Piedmont Avenue, Berkeley, CA 94720-2120, USA. rlee@demog.berkeley.edu  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0027-8424 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12878733 Approved no  
  Call Number Equine Behaviour @ team @ Serial 5465  
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