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Welsh Da,. (1973). The life of Sable Island's wild horses. Nature Canada, 2, 7–14.
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Welsh Da,. (1975). Population, behavioural, and grazing ecology of the Sable Island, Nova Scotia. Ph.D. thesis, Dalhousie University, Halifax.
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Wells, S., & von Goldschmidt-Rotschild, B. (1979). Social behaviour and relationships in a herd of Camargue horses. Z Tierpsychologie, 49, 363–380.
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Wells, P. G., Bhuller, Y., Chen, C. S., Jeng, W., Kasapinovic, S., Kennedy, J. C., et al. (2005). Molecular and biochemical mechanisms in teratogenesis involving reactive oxygen species. Toxicol Appl Pharmacol, 207(2 Suppl), 354–366.
Abstract: Developmental pathologies may result from endogenous or xenobiotic-enhanced formation of reactive oxygen species (ROS), which oxidatively damage cellular macromolecules and/or alter signal transduction. This minireview focuses upon several model drugs (phenytoin, thalidomide, methamphetamine), environmental chemicals (benzo[a]pyrene) and gamma irradiation to examine this hypothesis in vivo and in embryo culture using mouse, rat and rabbit models. Embryonic prostaglandin H synthases (PHSs) and lipoxygenases bioactivate xenobiotics to free radical intermediates that initiate ROS formation, resulting in oxidation of proteins, lipids and DNA. Oxidative DNA damage and embryopathies are reduced in PHS knockout mice, and in mice treated with PHS inhibitors, antioxidative enzymes, antioxidants and free radical trapping agents. Thalidomide causes embryonic DNA oxidation in susceptible (rabbit) but not resistant (mouse) species. Embryopathies are increased in mutant mice deficient in the antioxidative enzyme glucose-6-phosphate dehydrogenase (G6PD), or by glutathione (GSH) depletion, or inhibition of GSH peroxidase or GSH reductase. Inducible nitric oxide synthase knockout mice are partially protected. Inhibition of Ras or NF-kB pathways reduces embryopathies, implicating ROS-mediated signal transduction. Atm and p53 knockout mice deficient in DNA damage response/repair are more susceptible to xenobiotic or radiation embryopathies, suggesting a teratological role for DNA damage, consistent with enhanced susceptibility to methamphetamine in ogg1 knockout mice with deficient repair of oxidative DNA damage. Even endogenous embryonic oxidative stress carries a risk, since untreated G6PD- or ATM-deficient mice have increased embryopathies. Thus, embryonic processes regulating the balance of ROS formation, oxidative DNA damage and repair, and ROS-mediated signal transduction may be important determinants of teratological risk.
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Wells, D. L., & Millsopp, S. (2009). Lateralized behaviour in the domestic cat, Felis silvestris catus. Anim. Behav., 78(2), 537–541.
Abstract: Lateralized behaviour in the felids has been subject to little investigation. We examined the paw use of 42 domestic cats on three tasks designed to determine whether the animals performed asymmetrical motor behaviour. The influence of the cats' sex and age on their paw preferences was also explored. The distribution of the cats' paw preferences differed significantly between the three tasks. Task 1, the most complex exercise involving retrieval of a food treat from an empty jar, encouraged the most apparent display of lateralized behaviour, with all but one animal showing a strong preference to use either their left or right paw consistently. Tasks 2 (an exercise involving reaching for a toy suspended overhead) and 3 (a challenge involving reaching for a toy moving along the ground) encouraged ambilateral motor performance. Lateralized behaviour was strongly sex related. Male and female cats showed paw preferences at the level of the population, but in opposite directions. Females had a greater preference for using their right paw; males were more inclined to adopt their left paw. Feline age was unrelated to either strength or direction of preferred paw use. Overall, the findings suggest that there are two distinct populations of paw preference in the cat that cluster strongly around the animals' sex. The results also point to a relationship between lateralized behaviour and task complexity. More apparent patterns of lateralized behaviour were evident on more complex manipulatory tasks, hinting at functional brain specialization in this species.
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Wells Sm, G. - R. (1979). Social behaviour and relationship in a herd of Carmargue horses. Z. Tierpsychol., 49, 363–380.
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Weissing, F. J. (2011). Animal behaviour: Born leaders. Nature, 474(7351), 288–289.
Abstract: Social animals face a dilemma. To reap the benefits of group living, they have to stay together. However, individuals differ in their preferences as to where to go and what to do next. If all individuals follow their own preferences, group coherence is undermined, resulting in an outcome that is unfavourable for everyone. Neglecting one's own preferences and following a leader is one way to resolve this coordination problem. But what attributes make an individual a 'leader'? A modelling study by Johnstone and Manica1 illuminates this question.
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Weiss, D. J., Kralik, J. D., & Hauser, M. D. (2001). Face processing in cotton-top tamarins (Saguinus oedipus). Anim. Cogn., 3(4), 191–205.
Abstract: Current research on face processing in primates has focused on a few species, mostly macaques and chimpanzees; to date, only one New World monkey, the squirrel monkey, has been tested. We explored face processing, and the inversion effect in particular, in a New World primate species, the cotton-top tamarin (Saguinus oedipus). In phase 1 of our study, we trained subjects to discriminate between two faces and two scrambled faces; we then presented the tamarins with a series of novel probes in order to determine the features underlying classification. Results showed that the tamarins relied on the external contour of the face for discrimination more than the internal features and their configuration. Statistical analyses revealed no differences in accuracy or response times to upright versus inverted stimuli, and thus no inversion effect. In phase 2, we provided subjects with additional training on the face versus scrambled face discrimination task in order to focus their attention on the configuration of the internal features. Accuracy data revealed individual differences in how tamarins classified these stimuli, even though each subject was trained in the same way. In phase 3, we tested for generalization to a new set of face stimuli, as well as for the capacity to show an inversion effect. For one subject who attended to the configuration of internal features, we found significant evidence of generalization, but no evidence for an inversion effect.
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Weiss, A., King, J. E., & Figueredo, A. J. (2000). The heritability of personality factors in chimpanzees (Pan troglodytes). Behav Genet, 30(3), 213–221.
Abstract: Human personality and behavior genetic studies have resulted in a growing consensus that five heritable factors account for most variance in human personality. Prior research showed that chimpanzee personality is composed of a dominance-related factor and five human-like factors--Surgency, Dependability, Emotional Stability, Agreeableness, and Openness. Genetic, shared zoo, and nonshared environmental variance components of the six factors were estimated by regressing squared phenotypic differences of all possible pairs of chimpanzees onto 1 – Rij, where Rij equals the degree of relationship and a variable indicating whether the pair was housed in the same zoo. Dominance showed significant narrow-sense heritability. Shared zoo effects accounted for only a negligible proportion of the variance for all factors.
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Weishaupt, M. A., Wiestner, T., von Peinen, K., Waldern, N., Roepstorff, L., van Weeren, R., et al. (2006). Effect of head and neck position on vertical ground reaction forces and interlimb coordination in the dressage horse ridden at walk and trot on a treadmill. Equine Vet J Suppl, (36), 387–392.
Abstract: REASONS FOR PERFORMING STUDY: Little is known in quantitative terms about the influence of different head-neck positions (HNPs) on the loading pattern of the locomotor apparatus. Therefore it is difficult to predict whether a specific riding technique is beneficial for the horse or if it may increase the risk for injury. OBJECTIVE: To improve the understanding of forelimb-hindlimb balance and its underlying temporal changes in relation to different head and neck positions. METHODS: Vertical ground reaction force and time parameters of each limb were measured in 7 high level dressage horses while being ridden at walk and trot on an instrumented treadmill in 6 predetermined HNPs: HNP1 – free, unrestrained with loose reins; HNP2 – neck raised, bridge of the nose in front of the vertical; HNP3 – neck raised, bridge of the nose behind the vertical; HNP4 – neck lowered and flexed, bridge of the nose considerably behind the vertical; HNP5 – neck extremely elevated and bridge of the nose considerably in front of the vertical; HNP6 – neck and head extended forward and downward. Positions were judged by a qualified dressage judge. HNPs were assessed by comparing the data to a velocity-matched reference HNP (HNP2). Differences were tested using paired t test or Wilcoxon signed rank test (P<0.05). RESULTS: At the walk, stride duration and overreach distance increased in HNP1, but decreased in HNP3 and HNP5. Stride impulse was shifted to the forehand in HNP1 and HNP6, but shifted to the hindquarters in HNP5. At the trot, stride duration increased in HNP4 and HNP5. Overreach distance was shorter in HNP4. Stride impulse shifted to the hindquarters in HNP5. In HNP1 peak forces decreased in the forelimbs; in HNP5 peak forces increased in fore- and hindlimbs. CONCLUSIONS: HNP5 had the biggest impact on limb timing and load distribution and behaved inversely to HNP1 and HNP6. Shortening of forelimb stance duration in HNP5 increased peak forces although the percentage of stride impulse carried by the forelimbs decreased. POTENTIAL RELEVANCE: An extremely high HNP affects functionality much more than an extremely low neck.
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