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Author Uehara, T.; Yokomizo, H.; Iwasa, Y. doi  openurl
  Title Mate-choice copying as Bayesian decision making Type Journal Article
  Year 2005 Publication The American naturalist Abbreviated Journal Am Nat  
  Volume 165 Issue 3 Pages 403-410  
  Keywords Animals; *Bayes Theorem; *Choice Behavior; Female; Male; *Models, Biological; *Sexual Behavior, Animal  
  Abstract Mate-choice copying by females has been reported in fishes (e.g., guppies) and lekking birds. Presumably, females assess males' quality using both information from direct observation of males and information acquired by observing other females' choices. Here, we study mathematically the conditions under which mate-choice copying is advantageous on the basis of Bayesian decision theory. A female may observe the mate choice of another female, called the model female, who has performed an optimal choice based on her own judgment. The conditions required for the focal female to choose the same mate as that chosen by the model female should depend on the male's appearance to her, the reliability of her own judgment of male quality, and the reliability of the model females. When three or more females are involved, the optimal mate choice critically depends on whether multiple model females make decisions independently or they themselves copy the choices of others. If two equally reliable females choose different males, the choice of the second female, made knowing the choice of the first, should have a stronger effect on the choice of the third (focal) female. This “last-choice precedence” should be tested experimentally.  
  Address (down) Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka 812-8581, Japan. uehara@bio-math.biology.kyushu-u.ac.jp  
  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 1537-5323 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15729669 Approved no  
  Call Number Serial 1821  
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Author Conradt, L.; Roper, T.J. url  doi
openurl 
  Title Consensus decision making in animals Type Journal Article
  Year 2005 Publication Trends in Ecology & Evolution (Personal Edition) Abbreviated Journal Trends Ecol Evol  
  Volume 20 Issue 8 Pages 449-456  
  Keywords  
  Abstract Individual animals routinely face decisions that are crucial to their fitness. In social species, however, many of these decisions need to be made jointly with other group members because the group will split apart unless a consensus is reached. Here, we review empirical and theoretical studies of consensus decision making, and place them in a coherent framework. In particular, we classify consensus decisions according to the degree to which they involve conflict of interest between group members, and whether they involve either local or global communication; we ask, for different categories of consensus decision, who makes the decision, what are the underlying mechanisms, and what are the functional consequences. We conclude that consensus decision making is common in non-human animals, and that cooperation between group members in the decision-making process is likely to be the norm, even when the decision involves significant conflict of interest.  
  Address (down) Department of Biology and Environmental Science, John Maynard Smith Building, University of Sussex, Brighton, UK, BN1 9QG. L.Conradt@sussex.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 0169-5347 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16701416 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4802  
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Author Lewis, K.P.; Jaffe, S.; Brannon, E.M. doi  openurl
  Title Analog number representations in mongoose lemurs (Eulemur mongoz): evidence from a search task Type Journal Article
  Year 2005 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 8 Issue 4 Pages 247-252  
  Keywords Analysis of Variance; Animals; *Behavior, Animal; *Feeding Behavior; Female; Lemuridae/*psychology; Male; Mathematics; Odors; Smell/physiology; Time Factors  
  Abstract A wealth of data demonstrating that monkeys and apes represent number have been interpreted as suggesting that sensitivity to number emerged early in primate evolution, if not before. Here we examine the numerical capacities of the mongoose lemur (Eulemur mongoz), a member of the prosimian suborder of primates that split from the common ancestor of monkeys, apes and humans approximately 47-54 million years ago. Subjects observed as an experimenter sequentially placed grapes into an opaque bucket. On half of the trials the experimenter placed a subset of the grapes into a false bottom such that they were inaccessible to the lemur. The critical question was whether lemurs would spend more time searching the bucket when food should have remained in the bucket, compared to when they had retrieved all of the food. We found that the amount of time lemurs spent searching was indicative of whether grapes should have remained in the bucket, and furthermore that lemur search time reliably differentiated numerosities that differed by a 1:2 ratio, but not those that differed by a 2:3 or 3:4 ratio. Finally, two control conditions determined that lemurs represented the number of food items, and neither the odor of the grapes, nor the amount of grape (e.g., area) in the bucket. These results suggest that mongoose lemurs have numerical representations that are modulated by Weber's Law.  
  Address (down) Department of Anthropology, Washington University, St. Louis, MO 63130-4899, USA  
  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 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15660208 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2497  
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Author Overdorff, D.J.; Erhart, E.M.; Mutschler, T. doi  openurl
  Title Does female dominance facilitate feeding priority in black-and-white ruffed lemurs (Varecia variegata) in southeastern Madagascar? Type Journal Article
  Year 2005 Publication American journal of primatology Abbreviated Journal Am. J. Primatol.  
  Volume 66 Issue 1 Pages 7-22  
  Keywords Agonistic Behavior; Animals; Eating/physiology; Feeding Behavior/*physiology; Female; Leadership; Lemuridae/*physiology; Madagascar; Male; Observation; Sex Factors; *Social Dominance  
  Abstract Although many Malagasy lemurs are thought to be female dominant and to have female feeding priority, to date the relationship between these behaviors has been rigorously established only in Lemur catta, and other ways that females might achieve feeding priority have not been examined closely. Erhart and Overdorff [International Journal of Primatology 20:927-940, 1999] suggested that one way female primates achieve feeding priority is to initiate and lead groups to food, thereby gaining access to the food first and positively influencing their food intake compared to other group members. Here we describe female dominance patterns and potential measures of feeding priority in two groups of black-and-white ruffed lemurs (Varecia variegata) that were observed over a 15-month period in southeastern Madagascar. We predicted that the females would 1) be consistently dominant to males, 2) lead groups to food sources more often than males, and 3) have higher feeding rates compared to males when they arrived at food sources first. The results were dissimilar between the study groups. During the study, the oldest adult female in group 1 died. There was no evidence for female dominance in this group, and the remaining (likely natal) female did not lead the group more often, nor did she have a higher food intake than males. Group 1 dispersed shortly after the time frame reported here. In contrast, the resident female in group 2 was dominant to group males (based on agonistic interactions), led the group to food sources more often, and experienced a higher food intake when she arrived first at a food source. How these patterns vary over time and are influenced by the number of females in groups, group stability, food quality, and reproductive condition will be examined in future analyses.  
  Address (down) Department of Anthropology, University of Texas, Austin, Texas 78712-1086, USA. overdorff@mail.utexas.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 0275-2565 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15898069 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4110  
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Author Hare, B.; Plyusnina, I.; Ignacio, N.; Schepina, O.; Stepika, A.; Wrangham, R.; Trut, L. doi  openurl
  Title Social cognitive evolution in captive foxes is a correlated by-product of experimental domestication Type Journal Article
  Year 2005 Publication Current biology : CB Abbreviated Journal Curr Biol  
  Volume 15 Issue 3 Pages 226-230  
  Keywords Animals; *Animals, Domestic; Cognition/*physiology; *Cues; *Evolution; Foxes/*physiology; *Selection (Genetics); Social Behavior; Species Specificity  
  Abstract Dogs have an unusual ability for reading human communicative gestures (e.g., pointing) in comparison to either nonhuman primates (including chimpanzees) or wolves . Although this unusual communicative ability seems to have evolved during domestication , it is unclear whether this evolution occurred as a result of direct selection for this ability, as previously hypothesized , or as a correlated by-product of selection against fear and aggression toward humans--as is the case with a number of morphological and physiological changes associated with domestication . We show here that fox kits from an experimental population selectively bred over 45 years to approach humans fearlessly and nonaggressively (i.e., experimentally domesticated) are not only as skillful as dog puppies in using human gestures but are also more skilled than fox kits from a second, control population not bred for tame behavior (critically, neither population of foxes was ever bred or tested for their ability to use human gestures) . These results suggest that sociocognitive evolution has occurred in the experimental foxes, and possibly domestic dogs, as a correlated by-product of selection on systems mediating fear and aggression, and it is likely the observed social cognitive evolution did not require direct selection for improved social cognitive ability.  
  Address (down) Department of Anthropology, Harvard University, Cambridge, MA 02138, USA. hare@eva.mpg.de  
  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 0960-9822 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15694305 Approved no  
  Call Number refbase @ user @ Serial 594  
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Author Rhodin, M.; Johnston, C.; Holm, K.R.; Wennerstrand, J.; Drevemo, S. openurl 
  Title The influence of head and neck position on kinematics of the back in riding horses at the walk and trot Type Journal Article
  Year 2005 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 37 Issue 1 Pages 7-11  
  Keywords Acceleration; Animals; Back/*physiology; Biomechanics; Exercise Test/veterinary; Female; Gait/*physiology; Head/*physiology; Horses/*physiology; Male; Movement/physiology; Neck/*physiology; Walking/physiology  
  Abstract REASONS FOR PERFORMING STUDY: A common opinion among riders and in the literature is that the positioning of the head and neck influences the back of the horse, but this has not yet been measured objectively. OBJECTIVES: To evaluate the effect of head and neck position on the kinematics of the back in riding horses. METHODS: Eight Warmblood riding horses in regular work were studied on a treadmill at walk and trot with the head and neck in 3 different predetermined positions achieved by side reins attached to the bit and to an anticast roller. The 3-dimensional movement of the thoracolumbar spine was measured from the position of skin-fixed markers recorded by infrared videocameras. RESULTS: Head and neck position influenced the movements of the back, especially at the walk. When the head was fixed in a high position at the walk, the flexion-extension movement and lateral bending of the lumbar back, as well as the axial rotation, were significantly reduced when compared to movements with the head free or in a low position. At walk, head and neck position also significantly influenced stride length, which was shortest with the head in a high position. At trot, the stride length was independent of head position. CONCLUSIONS: Restricting and restraining the position and movement of the head and neck alters the movement of the back and stride characteristics. With the head and neck in a high position stride length and flexion and extension of the caudal back were significantly reduced. POTENTIAL RELEVANCE: Use of side reins in training and rehabilitation programmes should be used with an understanding of the possible effects on the horse's back.  
  Address (down) Department of Anatomy, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden  
  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 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15651727 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3657  
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Author Kobayashi, K.; Jackowiak, H.; Frackowiak, H.; Yoshimura, K.; Kumakura, M.; Kobayashi, K. openurl 
  Title Comparative morphological study on the tongue and lingual papillae of horses (Perissodactyla) and selected ruminantia (Artiodactyla) Type Journal Article
  Year 2005 Publication Italian Journal of Anatomy and Embryology = Archivio Italiano di Anatomia ed Embriologia Abbreviated Journal Ital J Anat Embryol  
  Volume 110 Issue 2 Suppl 1 Pages 55-63  
  Keywords Animals; Artiodactyla/*anatomy & histology/physiology; Cattle; Connective Tissue/physiology/ultrastructure; Feeding Behavior/physiology; Goats/anatomy & histology/physiology; Horses/anatomy & histology/physiology; Mastication/physiology; Microscopy, Electron, Scanning; Perissodactyla/*anatomy & histology/physiology; Tongue/physiology/*ultrastructure  
  Abstract A common characteristic of horses, Rocky Mountain goats, and cattle is that they all have a well developed lingual prominence on the dorsal surface of the posterior area of the tongue. Foliate papillae were found in the horse studied but not in the goat or in cattle. The horse filiform papillae had a long and slender external form with a thin and slender CTC, while in the goat and cattle the external form consisted of a large thick main process and the CTC consisted of a bundle of numerous rod-shaped protrusions. The special papilla found on the lingual prominence resembled larger filiform-like papillae in the horses; however, in the goat and cattle it was a very thick and large tongue like papillae. The horses had two large vallate papillae, while the goat and cattle had 15 or more vallate papillae at the posterior area of the lingual prominence. This suggests that the fine structure of horse tongues may display a more primitive pattern than that present in goats and cattle.  
  Address (down) Department of Anatomy, School of Dentistry at Niigata, The Nippon Dental University, Niigata, Japan. kobayashi@ngt.ndu.ac.jp  
  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 1122-6714 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16101021 Approved no  
  Call Number Serial 1887  
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Author Smith, D.G.; Pearson, R.A. doi  openurl
  Title A review of the factors affecting the survival of donkeys in semi-arid regions of sub-Saharan Africa Type Journal Article
  Year 2005 Publication Tropical Animal Health and Production Abbreviated Journal Trop Anim Health Prod  
  Volume 37 Suppl 1 Issue Pages 1-19  
  Keywords Africa South of the Sahara; Animal Nutrition Physiology; Animals; Behavior, Animal; Cattle; Equidae/growth & development/*physiology; Socioeconomic Factors  
  Abstract The large fluctuations seen in cattle populations during periods of drought in sub-Saharan Africa are not evident in the donkey population. Donkeys appear to have a survival advantage over cattle that is increasingly recognized by smallholder farmers in their selection of working animals. The donkey's survival advantages arise from both socioeconomic and biological factors. Socioeconomic factors include the maintenance of a low sustainable population of donkeys owing to their single-purpose role and their low social status. Also, because donkeys are not usually used as a meat animal and can provide a regular income as a working animal, they are not slaughtered in response to drought, as are cattle. Donkeys have a range of physiological and behavioural adaptations that individually provide small survival advantages over cattle but collectively may make a large difference to whether or not they survive drought. Donkeys have lower maintenance costs as a result of their size and spend less energy while foraging for food; lower energy costs result in a lower dry matter intake (DMI) requirement. In donkeys, low-quality diets are digested almost as efficiently as in ruminants and, because of a highly selective feeding strategy, the quality of diet obtained by donkeys in a given pasture is higher than that obtained by cattle. Lower energy costs of walking, longer foraging times per day and ability to tolerate thirst may allow donkeys to access more remote, under-utilized sources of forage that are inaccessible to cattle on rangeland. As donkeys become a more popular choice of working animal for farmers, specific management practices need to be devised that allow donkeys to fully maximize their natural survival advantages.  
  Address (down) Department of Agriculture and Forestry, University of Aberdeen, Aberdeen, AB24 3FX, Scotland, UK. d.g.smith@abdn.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 0049-4747 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16335068 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4231  
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Author König, H.E.; Wissdorf, H.; Probst, A.; Macher, R.; Voß, S.; Polsterer, E. url  openurl
  Title Considerations about the function of the mimic muscles and the vomeronasal organ of horses during the Flehmen reaction Type Journal Article
  Year 2005 Publication Pferdeheilkunde Abbreviated Journal  
  Volume 21 Issue 4 Pages 297-300  
  Keywords Anatomy; Behaviour; Flehmen reaction; Horse; Vomeronasal organ  
  Abstract Additional to the olfactory epithelium, the equine vomeronasal organ serves to the perception of odorous substances and specially for pheromones. In a middle-size horse this organ has an extension in length from an imaginary transverse plane about 10 cm caudally the nostrils to a transverse plane through the middle of the second premolar tooth. During the Flehmen reaction the levator labii superior, nasolabial, caninus and lateralis nasi muscles contract. The upper lip and the tip of the nose are lifted. The opening of the nostrils is narrowed, caused by the convergence of the plate and horn of the alar cartilage. In this manner in case of Flehmen reaction air is directly conducted towards the opening of the vomeronasal organ into the nasal cavity during inspiration. During the “Flehmen” horses assume a characteristic posture.  
  Address (down) Department für Pathobiologie (Institut für Anatomie), Veterinärmedizinische Universität Wien, Veterinärplatz 1, A-1210 Wien, Austria  
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  Area Expedition Conference  
  Notes Export Date: 21 October 2008; Source: Scopus Approved yes  
  Call Number Equine Behaviour @ team @ Serial 4554  
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Author Horner, V.; Whiten, A. doi  openurl
  Title Causal knowledge and imitation/emulation switching in chimpanzees (Pan troglodytes) and children (Homo sapiens) Type Journal Article
  Year 2005 Publication Animal cognition Abbreviated Journal Anim. Cogn.  
  Volume 8 Issue 3 Pages 164-181  
  Keywords Animals; Child Behavior; Child, Preschool; *Concept Formation; Female; Humans; *Imitative Behavior; *Learning; Male; Pan troglodytes; *Problem Solving; Psychomotor Performance; *Social Environment; Species Specificity  
  Abstract This study explored whether the tendency of chimpanzees and children to use emulation or imitation to solve a tool-using task was a response to the availability of causal information. Young wild-born chimpanzees from an African sanctuary and 3- to 4-year-old children observed a human demonstrator use a tool to retrieve a reward from a puzzle-box. The demonstration involved both causally relevant and irrelevant actions, and the box was presented in each of two conditions: opaque and clear. In the opaque condition, causal information about the effect of the tool inside the box was not available, and hence it was impossible to differentiate between the relevant and irrelevant parts of the demonstration. However, in the clear condition causal information was available, and subjects could potentially determine which actions were necessary. When chimpanzees were presented with the opaque box, they reproduced both the relevant and irrelevant actions, thus imitating the overall structure of the task. When the box was presented in the clear condition they instead ignored the irrelevant actions in favour of a more efficient, emulative technique. These results suggest that emulation is the favoured strategy of chimpanzees when sufficient causal information is available. However, if such information is not available, chimpanzees are prone to employ a more comprehensive copy of an observed action. In contrast to the chimpanzees, children employed imitation to solve the task in both conditions, at the expense of efficiency. We suggest that the difference in performance of chimpanzees and children may be due to a greater susceptibility of children to cultural conventions, perhaps combined with a differential focus on the results, actions and goals of the demonstrator.  
  Address (down) Centre for Social Learning and Cognitive Evolution, School of Psychology, University of St Andrews, St Andrews, KY16 9JU, UK. vkh1@st-andrews.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 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15549502 Approved no  
  Call Number refbase @ user @ Serial 732  
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