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121.
MURRAY LEAF 《American anthropologist》1971,73(1):267-268
A linguistico-semantic pattern associated with the designation of foods in English can be used in convenient classroom demonstrations of the concept of a cultural code and its importance. 相似文献
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Abstract Birds have been widely regarded as a key element in monitoring biodiversity both in Australia and elsewhere. We believe that, although birds are unlikely to be an umbrella or indicator taxon for other biota (other vertebrates, invertebrates, plants, microorganisms), they do represent a taxon that can be monitored more easily and with less effort per datum than other biotic components. It has been shown by the great participation rate of lay observers (whom we call monitors) in several schemes (notably the Birds Australia Atlas programs) that there is a capacity to mobilize the public to undertake bird surveying. Although there are many limitations to acquiring high‐quality information (scale, dynamism, mobility, irruptiveness, paucity of monitors over much of the rangelands), we think that these can be dealt with to allow the use of birds as a key component of biodiversity monitoring. We outline some of the possible options for statistically characterizing monitoring data for rangeland birds. 相似文献
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Abstract Ecologists have long sought to understand why some species are rare and others common. For the most part, inconsistent relationships between local rarity and underlying mechanisms have emerged. One possibility for this inconsistency is that locally rare species may not always be rare. However, it is largely unknown whether most locally rare species in a community possess the capacity to become abundant elsewhere in their geographical range. Here, we identified 57 locally rare plant species of open forest in south‐eastern Australia. We found that most of these species (91%) occurred in higher abundance at other sites within their geographical range (somewhere‐abundant species), while the remaining small percentage of locally rare species were consistently rare (everywhere‐sparse species). Somewhere‐abundant species had significantly smaller seeds on average than everywhere‐sparse species in cross‐species regression analysis. This pattern was not maintained when the influence of other life‐history attributes was controlled for, or when phylogenetic relatedness among species was considered explicitly in phylogenetic regression analysis. In both cross‐species and phylogenetic regressions, somewhere‐abundant and everywhere‐sparse species did not differ significantly with respect to growth form, height, regeneration‐after‐fire strategy, or dispersal. Our findings provide further evidence for the notion that theories to account for local rarity which are couched in terms of within‐community interactions alone are incomplete for the majority of species, because they need to account for different outcomes in different places. 相似文献
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A nutrient, slant-board technique was developed in order to estimate the losses to roots of white clover (Trifolium repens L.), caused by the feeding of the larvae of Sitona weevils. In this preliminary experiment losses of up to 50% of root length were found. This simple technique was straightforward to use and has the potential for applications in a large range of root-pest/feeding studies. 相似文献
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