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161.
The flight responses of 750 female Calliphora vicina Robineau‐Desvoidy, 1830 (Diptera: Calliphoridae) are investigated in a wind tunnel bioassay. The attraction of C. vicina towards dead mice and seven different synthetic lures made from dimethyl trisulphide, mercaptoethanol and O‐cresol is compared. Responses towards natural odours and the three‐component synthetic kairomones depend on the flies' ovarian egg developmental status. The natural and three‐component lures also induce similar age‐dependent responses, although the dead mice lure yields a significantly higher attraction. Oriented flight increases with the number of chemicals in the synthetic kairomone; one‐, two‐ and three‐compound lures induce 13–25%, 32–43% and 62% attraction, respectively. Responses to one‐component lures are not significantly influenced by egg developmental status, whereas blends of two or three components are. Attraction levels increase in a stepwise manner both across egg developmental categories and with the number of compounds. The results suggest that the attractiveness of synthetic kairomones is influenced not only by the blowflies' physiological state, but also by the complexity of the lure. 相似文献
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L. ANDERS NILSSON LARS JONSSON LYDIA RASON EMILE RANDRIANJOHANY 《Biological journal of the Linnean Society. Linnean Society of London》1985,26(1):1-19
Anthecological relations between a long-spurred angraecoid orchid and pollinating Sphingidae are documented for the first time. In a primary forest on the Central Plateau of Madagascar Angraecum arachnites Schltr. was found to be pollinated by and adapted to a single species of hawk-moth, Panogena lingens (Butler), despite abundance of many concurrent Sphingidae of which several were also long-tongued. Furthermore, P. lingens was dimorphic in the length and breadth of its proboscis and only the morph with the longest and most slender proboscis was recorded to pollinate A. arachnites . Exclusive and precise adaptation to the latter morph of P. lingens existed in floral morphology and probably in other characteristics such as flowering phenology and chemical signalling. Several concurrently flowering orchid species were sharing P. lingens as a pollinator resource. The monophily in A. arachnites is interpreted as a result of a refined long-term specialization developed within an archaic evolutionary relationship in a relatively stable environment. The extraordinary number and diversity of long-spurred Orchidaceae in Madagascar appears to be a direct coevolutionary consequence of an Old-World-unique diversity of long-tongued archaic Sphingidae that has persisted in this isolated land. 相似文献
165.
ANDERS MARTINSSON 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1969,2(1):73-86
A principal method of mastering the 'publication explosion' should be a more consistent structural differentiation of publishing, thus enabling a better channelling of information. Besides subject specialization, this can be achieved by clearer distinction between local, national, and international spheres of interest and between idiographic and nomothetic aspects of papers. The 'publication explosion' is a consequence of a corresponding increase in research, and quantitative curbing of publication should not be applied to such an extent that it affects the universal availability of scientific results. More stringent selection, however, would reduce the volume of primary publishing considerably. Training of authors in publishing techniques would greatly ease the burden of routine labour for editors. This, and the organization of scientific serials and articles to meet modern bibliographic-documentalistic needs, present problems calling for urgent solution at an international level. 相似文献
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ANDERS WARÉN 《Zoologica scripta》1981,10(2):133-154
All species that have been described in Apicalia , except the type-species, are transferred to other eulimid genera. Three species earlier included in other genera and four new species are placed in Apicalia , viz. A. angulata sp.n. A, cicatricosa sp.n. A. echinasteri sp.n. (all three Queensland), and A. habei sp.n. (Japan). Those of which the hosts are known are all ectoparasites of asteroids. Two of the seven species previously included in Stilapex are excluded and four species earlier placed in other genera are transferred to Stilapex . The members of the latter genus are parasites of ophiuroids. Tropiometricola gen.n. is erected to include Stilifer sphaeroconcha Habe, a crinoid parasite. Parvioris gen.n. is described with Eulima fulvescens A. Adams as type species. A list of species described in eulimid genera and fitting Parvioris is given. P. australiensis sp.n. (W. Australia), P. blakeae sp.n. (Mauritius), P. mortoni sp.n. (Hong Kong), and P. noumeae sp.n. (New Caledonia) are described. Those species of which the host is known, are all ectoparasites of starfishes. 相似文献
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ANDERS JOHNSSON 《Physiologia plantarum》1973,28(1):40-50
Oscillations in transpiration and water uptake of individual, young oat plants have been studied. The free-running period of these oscillations was about 30 minutes. Conditions were reached under which the oscillations were sustained for about two days. Short perturbations were given to the transpiration oscillations, the perturbations consisting of a short time increase or decrease in the illumination. The phase shifts of the oscillations as well as the amplitude effects caused by these perturbations were investigated. Simultaneous recordings of transpiration and water uptake of a single plant showed that these functions were oscillating in phase. Both oscillations disappeared if the leaf was excised. 相似文献
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