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1.
Maria Piedade M. S. Oliveira Eliane S. Azevdo 《American journal of physical anthropology》1977,46(3):471-475
Two thousand four hundred and forty-four Brazilian school children were classified as Light, Medium and Dark according to a subjective judgment of the proportion of Negro admixture, and studied for weight, height, span and upper-segment/lower-segment (US/LS) ratio. The mean US/LS ratio decreases significantly as the proportion of Negro admixture increases giving an intermediate value for those children belonging to the Medium group for race. 相似文献
2.
Daniel Portela Wanderley de Medeiros Ariadna Valentina Lopes Carmen Silvia Zickel 《Flora》2007,202(7):513-520
The study was carried out in the Private Nature Reservation Nossa Senhora do Outeiro de Maracaípe, located along the southern coast of Pernambuco state, in the Nossa Senhora do Ó District (08°31′48″S and 35°01′05″W), Ipojuca municipality, northeastern Brazil. The reserve has 76.20 ha of tropical coastal vegetation (Restinga forest). The aims were to determine the existence of seasonal phenological pattern of woody species as a function of rainfall. During the study period, the rainfall was 26.8 mm in the driest month (November 2003) and 538.9 in the wettest (June 2004). Observations on flowering, fruiting, leaf fall, and leaf flushing were recorded monthly, during 16 months (April 2003 to July 2004). All species with a ground level perimeter >10 cm and represented by at least three individuals, were selected and tagged. A total of 51 species represented by 156 individuals were recorded. Leaf flushing and leaf fall did not have seasonal variation and the species continued to gain and loose leaves during the dry (August to February) and rainy (March to July) seasons. Flowering, when evaluated by the Fournier's percentage, varied between 1.9% and 20.2%, with maximum intensity in December 2003 (16.4%) and January 2004 (20.2%). Likewise, fruiting varied between 3.8% and 21.4% with the highest percentages in February (17.2%) and March (21.4%) 2004. The analysis comparing reproductive phenological patterns with monthly rainfall did not show a significant correlation, which may suggest investigations concerning other factors, including biotic ones, as pollination and/or dispersal modes, which can be influencing reproductive events of plants in the studied Restinga forest. 相似文献
3.
Washington Luiz da Silva Vieira Gindomar Gomes Santana Cristina Arzabe 《Biodiversity and Conservation》2009,18(1):55-66
Anuran reproductive activities in xeric environments are strongly influenced by local rainfall and temperatures. Anuran species
that inhabit the Caatinga biome in northeastern Brazil demonstrate numerous behavioral and reproductive strategies that avoid
or minimize the negative effects of elevated temperatures and scarce water resources on egg development. Among the various
anuran species found in the Caatinga region, members of the family Leptodactylidae demonstrate the greatest number of reproductive
modes adapted to a terrestrial life style while most of the Hylidae species are more susceptible to variations in water availability.
Laying eggs in foam nests is a common strategy among species that inhabit environments with open vegetation forms and water
resources that are restricted to only short periods during the year. Data concerning anuran communities in the localities
examined here indicated a greater diversity of reproductive modes in ponds with more diverse vegetation structures and longer
periods of water availability indicating that the deeper the temporary ponds (permitting a longer hydroperiod) the more diverse
will be the aquatic and bordering vegetation, and the richer will be the diversity of anuran species observed and the number
of reproductive modes encountered there. 相似文献
4.
A biostratigraphic study was carried out in the Lower Cretaceous Araripe basin, northeastern Brazil, allowing the recognition of several chronostratigraphic units: the Dom João (Jurassic?-Lower Cretaceous?), the Rio da Serra (Neocomian) and the Alagoas (Aptian/Albian) local stages. For the first time a large hiatus between the Rio da Serra and Alagoas local stages is carefully documented. The palynomorphs and the ostracode associations throughout the Jurassic?-Aptian/Albian sequence allow the interpretation of the paleoenvironmental evolution of the Araripe basin which otherwise confirms that a polycyclical sedimentation occurred in the basin, being one of the controlling factors on the distribution of ostracodes and palynomorphes. 相似文献
5.
Antonio R. Mendes Pontes Iran C. Normande Amaro C. A. Fernandes Patrícia F. Rosas Ribeiro Marina L. Soares 《Biodiversity and Conservation》2007,16(4):1175-1182
The purpose of this study was to investigate the population status of the common marmosets, Callithrix jacchus, in one of their main habitats, the northeastern Atlantic forest of Brazil, where only 2% of its original area remains as small and isolated forest fragments, to determine long-term viable populations. The study was carried out in 15 forest fragments, measuring from 3,478.3 ha (the largest) to 6 ha, which were invariably subjected to high human impact. Line transect surveys were carried out between January 2002 and December 2004, along transects measuring from 350 to 4,000 m, between 0500 h and 0900 h. Common marmosets were registered in 73% (n = 11) of the forest fragments, were not recorded in the largest one, the Coimbra Forest, and group sizes varied from 1 to 4 individuals. A negative significant relationship was detected between the size of the fragment and the number of sightings of common marmosets. It is shown that the number of groups of common marmosets dwelling in this highly impacted landscape is nowadays lower than necessary for long-term survival. Additionally, smaller fragments having more groups suggests that they live in total association with humans, which assure their subsistence through the supply of introduced and exotic foods. 相似文献
6.
J.D.S. Paz 《Palaeogeography, Palaeoclimatology, Palaeoecology》2006,241(2):247-266
The Codó Formation records the initial evolutionary stages of an intracontinental rift system formed along the Brazilian equatorial margin in the late Aptian. Deposits of this unit exposed on the eastern margin of the Grajaú Basin include gypsum, bituminous black shales and limestones. These lithologies were formed in a low energy, well stratified, anoxic and hypersaline lake system developed in a dominantly arid/semi-arid climate. This lacustrine succession is internally organized into three categories of shallowing-upward cycles, with the first- and second-order cycles being related to seismic activity associated with fault reactivations, and the third-order cycles recording climatic fluctuations. Studies emphasizing petrography and analysis of the geochemical tracers Fe, Mg, Sr, Mn, Na and Ca helped to identify the sedimentary facies that kept a primary signal, which were thus appropriate for isotopic investigations aiming paleoenvironmental and paleohydrologic reconstructions. The results of this study revealed a wide distribution of dominantly low carbon and oxygen isotope values in carbonates, ranging from − 5.69‰ to − 13.02‰ and from − 2.71‰ to − 10.80‰, respectively. This paper demonstrates that at least in the particular case of oxygen, the isotope ratios vary according to seismically-induced shallowing-upward cycles, with values in general lower at their bases, where central lake deposits dominate, and progressively higher upward, where marginal lake deposits are more widespread. In addition to confirming a depositional signature for the analysed samples, this behavior allowed the development of a seismic-induced isotope model. The lighter isotope ratios appear to be related to flooding events promoted by subsidence, which resulted in the development of a perennial lake system, while heavier isotope values are related to ephemeral lake phases favored by uplift and/or increased stability. Furthermore, the results show that a closed lake system dominated, as indicated by the overall good positive covariance (i.e., + 0.42 to + 0.43) between the carbon and oxygen isotopes, though open phases are also recorded by negative covariance values of − 0.36. During closed phases, the δ18O displayed the highest range of variation (i.e., − 3.63‰ to − 4.89‰) due to increased residence time, while this variation was low (i.e., − 0.09‰ to − 1.87‰) during open lake phases, when there was a balance in the water isotope composition maintained by continuous basin inflow. 相似文献
7.
The objectivity of several anthropometric measurements were tested in two institutes on the same subjects. In many cases systematic differences are to be expected: 1. Girth measurements tend to differences in the same direction. 2. The comparability of skeletal measurements is often uncertain; some measurements tend to give lower, other ones higher figures. Biacromial diameter and radio-ulnar epicondylar width do not reveal systematic differences. 3. Skinfold thicknesses measured do not reveal systematic differences. 相似文献
8.
J H Himes 《American journal of physical anthropology》1989,79(1):77-80
The Spearman-Brown Prophesy formula, derived from psychometrics, may be used in anthropometric studies to describe the relationship between the intraclass reliability coefficient for a single measurement and the reliability resulting from the mean of replicate measurements. This theory may be applied to determine expected reliabilities of anthropometric protocols using replicate measurements and to determine the numbers of replicate measurements necessary to achieve desired levels of reliability. 相似文献
9.
Summary The frequencies of floral morphs in populations of tristylous Eichhornia paniculata often deviate from the theoretical expectation of equality. This variation is associated with the breakdown of tristyly and the evolution of self-fertilization. Differences in morph frequencies could result from selection pressures due to variable levels of insect visitation to populations and contrasting foraging behavior among the floral morphs. We estimated pollinator densities in 16 populations and quantified visitation sequences to morphs in five populations of E. paniculata in northeastern Brazil. Foraging behavior among floral morphs was measured as the frequency of visits to morphs relative to their frequency in the population (preference) and number of flights between inflorescences of the same versus different morphs (constancy). Pollinator density (number/m2/minute) was not correlated with population size, plant density or morph diversity. Pollinator densities varied most among populations of less than 200 plants. Whether pollinators discriminated among the morphs, depended on whether they primarily collected nectar or pollen. In four populations, nectar-feeding bees (Ancyloscelis and Florilegus spp.) and butterflies showed no consistent preference or constancy among the morphs. In contrast, pollen-collecting bees (Trigona sp.) visited a lower proportion of longstyled inflorescences than expected and tended to visit more mid-and short-styled inflorescences in succession, once they were encountered. Pollinator constancy for morphs did not result from differences in inflorescence production or spatial patchiness among the morphs. Although non-random pollinator visitation to morphs in heterostylous populations could potentially affect mating and hence morph frequencies, the observed visitation patterns in this study do not provide evidence that pollinators play a major role in influencing floral morph frequencies. 相似文献
10.
Analysis of nine characteristics on 1,205 males and 932 females from 12 tribes or groups of tribes indicated a poor relationship between morphology and language, as well as moderate agreement with the variability expected considering geography only. Two samples in the Xingu area studied during an interval of half a century (1897-1947) showed remarkable similarity. The conformity of the Caingang morphology with those of other tribes and the distinctiveness of the Xavante and Tenetehara has been amply confirmed. 相似文献
11.
An anthropometric investigation was designed to evaluate patterns of physical deterioration in Huntington's disease (HD). In this study a comprehensive set of measurements was taken including height, weight, body circumferences, skinfold thickness, and craniofacial, linear, and breadth components of the body, on 44 normal, 26 affected, and 70 at-risk individuals between 14 and 88 years of age. The anthropometric data were converted to z-scores using standards to adjust for age and sex differences. These scores were then adjusted for inter-family variation. There were significant differences among normal and affected individuals for all dimensions of body mass, as well as for several craniofacial and linear components of the body. Several significant differences were also found between normals and particular age cohorts of at-risk persons. HD gene carrier status was further assessed by factor analysis of the adjusted scores. 相似文献
12.
The last 10 years (1998–2007) were very productive and important in the study of early angiosperms in northeastern China. The new discoveries of the earliest well-documented records of angiosperms such as Archaefructus, as well as Hyrcantha decussata (= Sinocarpus decussatus), provided fresh knowledge for better understanding the primitive characters of the ancient angiosperms and also their aquatic (or wet) habitat and their herbaceous nature. Some new approaches such as the combination of molecular and morphological characters joined together to place Archaefructus in the angiosperm phylogenetic framework. These fossils demonstrate that we should expect more ancient angiosperms to be found in the pre-Cretaceous which will continue to add important new understanding to the nature of the origin and evolution of the angiosperms. 相似文献
13.
R D Singh 《American journal of physical anthropology》1974,40(2):221-226
Anthropometric studies in India have been conducted on a fairly large scale but the lack of uniform techniques has rendered data non-comparable. Here, the magnitude of differences in values on account of differences in techniques under two methods has been demonstrated by measuring the cranial height of 35 skulls in the Department of Anthropology, University of Lucknow, India. The direct method gives as much as 5 mm lower values than the subtraction method. Furthermore, the position of vertex relative to apex is highly variable. Such differences are likely to be more magnified in skulls with plano-occipitals. It is therefore re-emphasized that anthropometrists should employ uniform techniques, and adequately describe them so that the data remains comparable. 相似文献
14.
Anthropometric data collected in native populations of British Columbia in the late 19th century by Franz Boas were analyzed by two multivariate techniques. Multivariate analysis of variance was used to test physical classificatory units devised by Boas and an ad hoc classification based on local cultural units. Both were found to have some empirical validity. Mahalanobis' D (Mahalanobis, '30) was computed between pairs of local groups, for both sexes. From these a matrix of differences was prepared and diagrams drawn to illustrate phenetic relationships among samples. By this means one cluster of groups, Interior B.C. peoples, could be distinguished and other local samples appeared distinctly different from each other. It was concluded that in the absence of genealogical data by which to identify local populations, local cultural units are preferable to more inclusive units for making empirical comparisons and classifications. 相似文献
15.
J. S. Song 《Plant Ecology》1992,98(2):175-186
Previous classification systems of the subalpine coniferous forests, belonging to the class Vaccinio-Piceetea Br.-Bl. 1939, in northeastern Asia were reviewed based on phytosociological data of Korea and Japan. A new order, the Abieti nephrolepidis-Piceetalia jezoensis was proposed for the subalpine coniferous forests in the continental part of northeastern Asia. Its distribution range and subordinate vegetation units are as follows:Order Abieti nephrolepidis-Piceetalia jezoensis ordo nov.In Korea:Alliance Abieti nephrolepidis-Piceion jezoensis Song 1991Association Taxo-Pinetum pumilae Song et Nakanishi 1985Association Thujo-Abietetum nephrolepidis Song 1991Association Abieti koreanae-Piceetum jezoensis Song 1991Alliance Abietion koreanae Song 1991Association Saso-Abietetum koreanae Song et Nakanishi 1985Association Betulo saitoanae-Abietetum koreanae (Song et Nakanishi 1985) em. Song 1991In northeast China and Maritime Province of Siberia, U.S.S.R.: (one separate alliance level or the same alliance as Abieti nephrolepidis-Piceion jezoensis)Formation Abies nephrolepis form. (Wu 1980)Formation Picea jezoensis-Abies nephrolepis form. (Wu 1980)Generally the Abieti nephrolepidis-Piceetalia jezoensis develops under the dry and cool continental climate and on the monophylogenic Dark Brown Conifer Soil Group derived mostly from granite and granitic gneiss. The subalpine or subarctic coniferous forests in Hokkaido, Sakhalin and Southern Kuriles may also belong to the Abieti nephrolepidis-Piceetalia jezoensis because of their floristic composition and the historical relevance of plant geography. The subordinate vegetation units are as follows:Alliance Piceion jezoensis Suz.-Tok. ex Jinno et Suzuki 1973Association Piceo-Abietetum sachalinensis Ohba 1967Association Piceetum glehnii Suz.-Tok. ex Miyawaki 1988The Abieti veitchii-Piceetalia jezoensis hondoensis Miyawaki et al. 1968 seems to fit only to the subalpine coniferous forests of Honshu and Shikoku of the Japanese Archipelago. 相似文献
16.
G N van Vark 《Acta morphologica Neerlando-Scandinavica》1987,25(2):107-116
The study of human evolution has always been a major issue in physical anthropology. Since computers became available this study became a new dimension in that it became feasible to apply advanced mathematical multivariate methods which make use of morphometric data. However, looking back on what has been achieved so far with these methods, it must be admitted that the results obtained are often unsatisfactory. This has led to a certain lack of acceptance of these methods. In the present paper it is argued that very useful results may be obtained by applying more sophisticated multivariate methods which are specifically designed for the anthropological problems at issue. Three examples are given. The first deals with the controversy between "Creationism" on the one hand and "Evolutionism" on the other. Our results strongly support the Evolutionists' point of view. The second example deals with the reconstruction of human phylogeny. An investigation is discussed which has led to a startling new hypothesis concerning the evolution of man. The last example concerns a preliminary investigation of trends in human sexual dimorphism. The results obtained so far seem to support the opinion expressed by other workers that tendencies exist in our modern society which lead to changes in the present dimorphism. 相似文献
17.
W M Bass 《American journal of physical anthropology》1979,51(4):555-562
A review of publications over the last ten years of methods in the field of physical anthropology for determining age, sex, race and stature of human skeletal material is presented. Comparisons are made with the types of papers published in the previous ten years (1958-1968) in six categories: (1) Visual examination of bones (2) Anthropometric measurements of bones (3) Anthropometric measurements with subsequent use of statistics in the form of discriminate function analyses (4) Time and sequence of eruption of the teeth (5) X-ray examination of the internal structure of bone sections (6) Microscopic examination of the internal structure of bone. 相似文献
18.
19.
Effects of X chromosome on size and shape of body: an anthropometric investigation in 47,XXY males 总被引:1,自引:0,他引:1
J Varrela 《American journal of physical anthropology》1984,64(3):233-242
The effects of an extra X chromosome on size and shape of body and head were studied in 47,XXY males; 25 anthropometric measurements were recorded from 29 adult 47,XXY males and compared with those of male relatives and control males. In stature, arm length, leg length, triceps skinfold, and subscapular skinfold 47,XXY males were larger and in biacromial diameter, bideltoid breadth, wrist breadth, and in most head dimensions smaller than normal males. Arm length was increased less than leg length. Increase in stature seemed to be caused solely by increased leg length, and the somewhat feminine proportions in trunk were caused by decrease in biacromial diameter. Correlations of the body and head dimensions between 47,XXY males and their male relatives were found to be normal. The present findings support the earlier proposals that X chromosome carries genes which influence linear growth. It is suggested that the reduction in biacromial diameter is caused by lowered plasma testosterone level which may also have affected sitting height. The control of body and head dimensions seems to be maintained relatively normal. 相似文献
20.
A sample of 539 individuals, 188 males and 351 females from 35 to 93 years, from a rural area, were studied in order to show ear variability according to age and sex. The characters analyzed were: maximum length and breadth, lobe type, and their possible asymmetries. The individuals were also searched for Darwin’s tubercle. Paper presented at the 4th congress of the European Anthropology Association (Florence, Sept. 1984). 相似文献