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DAVID G. HAYS ENID MARGOLIS RAOUL NAROLL and DALE REVERE PERKINS 《American anthropologist》1972,74(5):1107-1121
Eleven focal colors are named by basic color terms in many languages. The most salient colors (black, white, and perhaps red) are named in all languages; the least salient of the set are named in fewer languages. Salience correlates with earliness of introduction, as measured by a scale of social evolution; with brevity of expression, as measured by phonemic length of basic color terms; with frequency of use, as measured by frequency of basic color terms in literary languages; and with frequency of mention in ethnographic literature. None of these correlations are established in the pioneer study of Berlin and Kay (1969), a study whose defects are well exposed by Durbin (1972) and Wescott (1970). The first two were documented respectively in Naroll (1970) and Durbin (1972); the last two are documented here. These four correlations independently support the Berlin-Kay color salience theory. They furnish a sound basis for further research on color term salience in particular and indeed on salience phenomena in general. We speculate that salience may be an important general principle of cultural evolution. 相似文献
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SOFIA MARQUES SILVA NADIA MORAES‐BARROS CAMILA C. RIBAS NUNO FERRAND JOÃO S. MORGANTE 《Biological journal of the Linnean Society. Linnean Society of London》2012,107(1):39-55
The identification of northern and southern components in different vertebrate species led researchers to accept a two‐component hypothesis for the Brazilian Atlantic forest (BAF). Nevertheless, neither a formal proposal nor a meta‐analysis to confirm this coincidence was ever made. Our main objective here was therefore to systematically test in how many vertebrate components the BAF could be divided by analysing existing empirical data. We used two approaches: (1) mapping and comparing the proposed areas of vertebrate endemism in the BAF and (2) analysing studies mentioning spatial subdivisions in distinct forest‐dependent vertebrates within the biome, by the use of panbiogeography. The four large‐scale endemism area components together with the six small‐scale panbiogeographical ones allowed the definition of three BAF greater regions, subdivided into nine vertebrate components, latitudinally and longitudinally organized. Empirical time estimates of the diversification events within the BAF were also reviewed. Diversification of these vertebrates occurred not only in the Pleistocene but also throughout the Miocene. Our results confirm the BAF's complex history, both in space and time. We propose that future research should be small‐scale and focused in the vertebrate components identified herein. Given the BAF's heterogeneity, studying via sections will be much more useful in identifying the BAF's historical biogeography. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ??, ??–??. 相似文献
45.
SVEIN DALE 《Ibis》2010,152(2):292-298
Natal dispersal distance and direction determine the likelihood that siblings will settle close together and hence the risk of inbreeding. Several studies have shown a sibling resemblance in dispersal distance, but few studies have analysed sibling resemblance in dispersal direction or the distance between siblings after dispersal at the landscape level. I studied the entire Norwegian population of Ortolan Buntings Emberiza hortulana, which is patchily distributed in an area covering c. 500 km2. Males and females did not differ in dispersal distance (overall median 3.7 km), but directions were different. Natal dispersal distances and directions were positively related within sibling pairs, but comparisons with control individuals suggested that any effects were due to spatial effects of configuration of habitat patches in the study area. Brother–sister pairs (n = 16) were at least as similar as brother–brother pairs (n = 18). Distance between siblings after natal dispersal increased with dispersal distance, but even so, five of 35 sibling pairs settled < 1 km apart, despite dispersal distances of 8.3–9.9 km for two of these pairs. Including movements later in life, eight sibling pairs were < 1 km apart at some time (four pairs of brothers and four brother–sister pairs), and in one case a brother mated with its sister. Another case of mating between close relatives (father and daughter) involved short female natal dispersal. These data indicate that female‐biased natal dispersal and long‐distance dispersal may reduce, but do not exclude, the possibility of inbreeding. 相似文献
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C. DALE BEERS 《The Journal of eukaryotic microbiology》1962,9(3):364-370
SYNOPSIS. Conchophthirus curtus is a thigmotrich that occurs on the gills of Unionid clams ( Elliptio complanatus in this study). The anterior third of the endoplasm, unlike the remainder, is relatively firm and without gastrioles; it contains an extensive aggregation of specialized endoplasmic granules and is therefore called granuloplasm. On the surface ventral to the granuloplasm is a thigmotactic area that bears closely set, strongly adherent cilia. There is no evidence that the granules are intracellular microorganisms; they are Feulgen-negative and do not divide, nor do they stain like bacteria. Cytochemical tests show that the granules contain neutral fat, fatty acid, phospholipid, glycogen, and mucin. The evidence indicates that the principal function of the granules and granuloplasm is the production of mucin, which is supplied to the underlying thigmotactic cilia, thereby conferring on them their adhesive properties. Thus, the granules and granuloplasm constitute a mucous organelle, and to the extent that they are osmiophilic and secretory they qualify as Golgi bodies and Golgi material, respectively. Since endoplasmic granule is a general term for any of the granules of protozoan endoplasm, it is recommended that the granules of the present study be called muciferous granules. 相似文献
47.
GECELE MATOS PAGGI JAMILLA ALVES TRINDADE SAMPAIO MANUELA BRUXEL CAMILA MARTINI ZANELLA MÁRCIA GÖETZE MIRIAM VALLI BÜTTOW CLARISSE PALMA‐SILVA FERNANDA BERED 《Botanical journal of the Linnean Society. Linnean Society of London》2010,164(3):317-325
Seed dispersal, population structure and the mating system of plant species can have great consequences on the genetic structure of populations. Vriesea gigantea is a bromeliad from southeastern Brazil which is self‐compatible and pollinator dependent for fruit set. Its populations are fertile in terms of the production of flowers, pollen, fruits and seeds. To assess the importance of seed supply for gene flow, colonization and distribution of adult individuals, the seed dispersal and population structure of V. gigantea were studied. Seeds are dispersed over short distances; most seeds land close to the mother plant. This pattern coincides with the reported aggregate distribution of bromeliad seedlings. Population structure results showed high seedling recruitment, because 51.3% developed into adults, although few juveniles reached this stage. This result is different from that for other bromeliad species from different habitat conditions. Seed dispersal and population structural patterns are consistent with previous molecular studies, revealing that V. gigantea populations are genetically structured, with low gene flow and a moderate outcrossing rate. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164 , 317–325. 相似文献
48.
DAVID P. TURNER SHAWN URBANSKI† DALE BREMER‡ STEVEN C. WOFSY† TILDEN MEYERS§ STITH T. GOWER¶ MATTHEW GREGORY 《Global Change Biology》2003,9(3):383-395
Vegetation light use efficiency is a key physiological parameter at the canopy scale, and at the daily time step is a component of remote sensing algorithms for scaling gross primary production (GPP) and net primary production (NPP) over regional to global domains. For the purposes of calibrating and validating the light use efficiency ( ε g) algorithms, the components of ε g– absorbed photosynthetically active radiation (APAR) and ecosystem GPP – must be measured in a variety of environments. Micrometeorological and mass flux measurements at eddy covariance flux towers can be used to estimate APAR and GPP, and the emerging network of flux tower sites offers the opportunity to investigate spatial and temporal patterns in ε g at the daily time step. In this study, we examined the relationship of daily GPP to APAR, and relationships of ε g to climatic variables, at four micrometeorological flux tower sites – an agricultural field, a tallgrass prairie, a deciduous forest, and a boreal forest. The relationship of GPP to APAR was close to linear at the tallgrass prairie site but more nearly hyperbolic at the other sites. The sites differed in the mean and range of daily ε g, with higher values associated with the agricultural field than the boreal forest. εg decreased with increasing APAR at all sites, a function of mid‐day saturation of GPP and higher ε g under overcast conditions. ε g was generally not well correlated with vapor pressure deficit or maximum daily temperature. At the agricultural site, a ε g decline towards the end of the growing season was associated with a decrease in foliar nitrogen concentration. At the tallgrass prairie site, a decline in ε g in August was associated with soil drought. These results support inclusion of parameters for cloudiness and the phenological status of the vegetation, as well as use of biome‐specific parameterization, in operational ε g algorithms. 相似文献
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Surface Changes Induced by Immune Serum on Eimeria tenella Sporozoites and Merozoites 总被引:2,自引:0,他引:2
ABSTRACT. The surface of merozoites and sporozoites of Eimeria tenella was affected by incubation with E. tenella -immune chicken serum (ICS). Normal chicken serum (NCS) and heat-inactivated ICS had no effect on the pellicular surface of either developmental stage. Sporozoites formed surface bulges or swellings after 10 min of incubation with ICS, and by 15 min postincubation, the morphology of the sporozoites was distorted by a surface coating of fibrinous material. Merozoites exposed to ICS were similarly coated, but surface swelling was not as severe. The coating formed rapidly and was seen as early as 5 min postincubation. Sporozoites incubated with heat-inactivated ICS supplemented with normal chicken serum were coated with a fibrinous material and in some cases lysed. These data indicated that complement must be present for the surface interaction to occur. 相似文献