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Duncan M. Watson David B. Croft 《Ethology : formerly Zeitschrift fur Tierpsychologie》1996,102(2):336-346
Age-related differences in the playfighting strategy of captive male red-necked wallabies Macropus rufogriseus banksianus was examined. Our purpose was to determine whether wallabies adjusted their play in response to their partner's age and, if so, how. The way in which a wallaby played was dependent on the relative age of its partner, and this pattern tended to be the same regardless of whether it was the initiator or reactor of the interaction. If a wallaby's partner was younger than itself it adopted a defensive strategy in which it self-handicapped by standing flat-footed, Pawing rather than Sparring, and by not using its full strength. Its greater rate of Shaking suggests that this act may function as an appeasement signal in play. Furthermore, it was highly tolerant of the tactics used by its younger partner and took the more active role in prolonging interactions. If, on the other hand, its partner was older than itself, it adopted an offensive strategy involving vigorous Sparring, increased time in the High-stance posture and a greater percentage of bouts that were of high intensity. Indeed, it played with even more vigour than when it playfought with wallabies of the same age as itself. Differences in the play of same-aged partners were in the non-fighting components of play, while those of differently-aged partners were in the fighting components. Play between same-aged partners, however, tended to be more stable and more competitive than that between partners of differing age. These results are discussed with emphasis on the compromises made in order for play to occur and the potential benefits to each partner of play in mixed-age class encounters. We briefly consider the implications of self-handicapping in the categorization of macropodid fights as play or aggression. 相似文献
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Sean Murphy G.Michael Blackburn Lindsay Sawyer Herman C. Watson 《International journal of biological macromolecules》1982,4(4):250-252
The preparation, purification and crystallization of porcine anhydroelastase using affinity chromatography which turkey-ovomucoid inhibitor is described. The structure of the active site at 3.5 Å (0.35 nm) resolution is compared with that of the native enzyme. An attempt is made to locate the substrate(Ala)4-Lys-Phe bound to anhydroelastase. 相似文献
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Thirty-seven species representing eight of the nine subtribes of the tribe Inuloideae-Compositae were examined for the presence of crystals in the achene wall, fibers within the phloem, and schizogenous resin canals in the aerial stem. Leaf hair type and the size of the widest xylem element were also recorded for each species. These comparative observations point to the presence of two major groups which are completely obscured by current taxonomic practice. Comparative palynological and cytological data already in the literature are readily interpreted in the light of this suggested grouping. 相似文献
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Chalmers Watson 《BMJ (Clinical research ed.)》1908,2(2483):290-291
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