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DENA P. MACMYNOWSKI TERRY L. ROOT GRANT BALLARD† GEOFFREY R. GEUPEL† 《Global Change Biology》2007,13(11):2239-2251
Climate-related changes associated with the California marine ecosystem have been documented; however, there are no studies assessing changes in terrestrial vertebrate phenology on the Pacific coast of western North America. We analyze the spring phenology of 21 Nearctic-Neotropical migratory songbird species in central and northern CA. Using observational and banding data at multiple sites, we evaluate evidence for a change in arrival timing being linked to either nonclimatic or multiscalar climatic explanations. Using correlation analysis, of the 13 species with a significant ( P <0.10) change in arrival, the arrival timing of 10 species (77%) is associated with both temperature and a large-scale climate oscillation index (El Niño Southern Oscillation, ENSO; North Atlantic Oscillation, NAO; and/or Pacific Decadal Oscillation, PDO) at least at one location. Eight of the 13 species (62%) are advancing their migratory timing. All species for which spring arrival is associated with climate at multiple locations are exhibiting changes ( n =5) and all species lacking evidence for association between migration phenology and climate ( n =3) exhibit no change. Migrants tend to arrive earlier in association with warmer temperatures, positive NAO indices, and stronger ENSO indices. Twelve species negatively correlate ( P ≤0.05) with local or regional temperature at least at one location; five species negatively correlate with ENSO. Eleven species' arrival is correlated ( P ≤0.05) with NAO; 10 are negatively associated. After an exhaustive literature search, this is apparently the first documentation of an association between NAO and migratory phenology in western North America. 相似文献
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GRANT GILLETT 《Bioethics》2009,23(6):330-339
Informed consent is the practical expression of the doctrine of autonomy. But the very idea of autonomy and conscious free choice is undercut by the view that human beings react as their unconscious brain centres dictate, depending on factors that may or may not be under rational control and reflection. This worry is, however, based on a faulty model of human autonomy and consciousness and needs close neurophilosophical scrutiny. A critique of the ethics implied by the model takes us towards a 'care of the self' view of autonomy and the subject's attunement to the truth as the crux of reasoning rather than the inner mental/neural state views of autonomy and human choice on offer at present. 相似文献
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GRANT A. HARPER 《Austral ecology》2007,32(3):305-314
Abstract Habitat selection of mammalian predators is known to be influenced by availability and distribution of prey. The habitat selection of feral cats on Stewart Island, southern New Zealand, was investigated using telemetry of radio‐tagged cats. Compositional analysis of the habitat selection of radio‐tagged cats showed they were using the available habitats non‐randomly. Feral cats avoided subalpine shrubland and preferentially selected podocarp‐broadleaf forest. The avoidance of subalpine shrubland by cats was probably due to a combination of the presence of a large aggressive prey species, Norway rats Rattus norvegicus, and the lack of rain‐impervious shelter there. Most cats also used subalpine shrubland more often in dry weather than in wet weather. Cats did not preferentially select all the other habitats with only smaller rat species, Rattus rattus and Rattus exulans, present however. Cats were probably further influenced by the availability of large trees, in podocarp‐broadleaf forest, that can provide shelter. Cats were also more active in dry rather than wet weather which supports this conclusion. Home ranges of feral cats on Stewart Island were some of the largest recorded, probably because of limited primary and alternative prey. 相似文献
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W. GRANT INGLIS 《Biological journal of the Linnean Society. Linnean Society of London》1991,44(2):121-139
Taxonomic and systematic theory is hopelessly confused because the term character has nine different, previously confused, meanings. After a historical analysis, it is shown that some form pairs, one used in taxonomy (= operational identification of phenetic patterns of character x individual spread) and the other in systematics (= theoretical analysis of patterns of taxonomy). On the basis of a stratigramy model, names are given to each usage and are defined for taxonomy, then systematics, as necessary: component : (tax.) a defined bit-or-piece of one individual (no syst. meaning); homology : (tax.) conceptual identity of components of several individuals, attributable (syst.) to common ancestry; homology avatar : (tax.) case of recognized homology which (syst.) shows broad phylogenetic continuity (e.g. eye) (= character sensu Sokal and Sneath); homolostratum/homology state : (tax.) specified condition of a homology avatar whose distribution (syst.) enables cladogenetic happenings to be identified (e.g. colour:red/green/blue/etc.) (= character state of Sokal and Sneath); character sensu stricto : (tax.) homolostratum limited to a taxon which (syst.), with hierarchy, identifies chronological sequences of most cladogenetic happenings; taxonomoids : (tax.) mixed group of homolostrata, including yet unknown characters, that identifies a taxon and so (syst.) has same role as characters (= roughly symplesiomorphies); Ante- (Ah) and Post-(Ph) happening characters : (tax.) the hierarchy levels immediately above and below an empty level which (syst.) reveal a cladistic happening (= roughly one usage of synapomorphies and apomorphies). 相似文献
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