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1.
太原地区现代人头骨的研究 总被引:15,自引:10,他引:5
本文报告了太原地区男、女组现代人头骨测量性状的基本统计量和非测量性状的出现情况,记述和讨论了它们的两侧差异和性别差异情况,建立了以多个项目测量值鉴定华北人头骨性别的判别函数。 相似文献
2.
Sixteen metrical and 18 non-metrical variants in aged Hooded seal skulls from Newfoundland, the Denmark Strait, and Jan Mayen were recorded. Relationships between the stocks were studied using univariate and multivariate techniques, after appropriate correction for age dependence of the metrical variants. No multivariate separation of the stocks was detected and it is concluded that there are little genetical differences between them. Therefore the null hypothesis that there is a high degree of intermixing between the stocks cannot be rejected. 相似文献
3.
Intraspecific multivariate data analyses of 27 metrical and 20 non-metrical characters were performed on skulls of L. albirostris (Gray, 1846) and L. acutus (Gray, 1826) to distinguish between possible populations from the eastern and the western North Atlantic.
The results from principal component (PC) analysis and partial least square (PLS) analysis suggest that the skulls of L. albirostris were taken from separate populations, whereas those of L. acutus were not.
A difference in the occurrence-patterns of the two species was found, indicating that the degree of intraspecific variation may be linked to the water-depth related distribution. 相似文献
The results from principal component (PC) analysis and partial least square (PLS) analysis suggest that the skulls of L. albirostris were taken from separate populations, whereas those of L. acutus were not.
A difference in the occurrence-patterns of the two species was found, indicating that the degree of intraspecific variation may be linked to the water-depth related distribution. 相似文献
4.
5.
Various non-metrical traits were examined in the supraorbital region in a series of skulls of recorded sex (147 males, 130 females), age (18-80 years) and provenance (Siena and surroundings), using a standard method of categorization and notation introduced by two of the authors in 1983. The results are discussed from a topographic-anatomical point of view in relation to trait variation and with respect to the usefulness of the method applied for population studies. 相似文献
6.
现代人头骨面部几项非测量性状的观察 总被引:4,自引:3,他引:1
用人类学观察法比较了中国云南、华北和欧洲现代人头骨的犬齿窝、颧骨缘突和梨状孔上外侧部膨隆的出现情况,以探讨其在人种、群体区分上是否有意义。结果:(1)在云南头骨,犬齿窝、颧骨缘突的出现率无性别差异,梨状孔上外侧部骨表面膨隆的出现率男性明显高于女性,而在欧洲头骨,这3项非测量必状的出现率男女间无差异。(2)上述3项性状,在中国云南和华北头骨(男性)的出现率无差异。(3)犬齿窝、梨状孔上外侧部骨表面膨隆的出现率,在现代欧洲人头骨明显高于现代中国人头骨。颧骨缘突的出现率在欧洲与中国现代人头骨上无差异。 相似文献
7.
中国和西方化石人头骨面部三项非测量性状的比较 总被引:3,自引:3,他引:0
采用传统的人类学观察方法,对一些中国和西方的化石人头骨模型的犬齿窝、颧骨缘结节和梨状孔上外侧部的膨隆情况进行观察比较,希望为研究头骨形态的发展变化及现代人起源问题,特别是中国现代人的起源提供一些值得参考的信息。得到如下提示:(1)在欧洲犬齿窝似乎是随着人类的进化逐渐出现的,(2)在化石人头骨上,颧骨缘结节的出现似看不出明显的地域差异,(3)梨状孔上外侧部的膨隆这一性状似乎在大荔头骨与其他中国化石人“不融洽”,而与欧洲尼人接近,这一现象可能反映了某种程度的基因交流。 相似文献
8.
R S Corruccini 《American journal of physical anthropology》1976,44(2):285-293
Cranial discrete or 'epigenetic" traits have been analyzed for interrelationships with measurements of the skull in a sample of American Negro males. Univariate t and multivariate T2 tests are used. It has been the previous consensus view that nonmetric and metric characters are unrelated. Statistically significant associations between the total of 50 discrete and 23 metrical characters, however, are much more frequent than would be expected through random distribution. Multivariate analysis supplements simpler statistics by synthesizing patterns of variation within regions of the skull, identifying many interrelations of skull size and shape with discrete traits. A low but observable general influence is exerted upon nonmetric morphology by metrical variation of the human skull (or vice versa). 相似文献
9.
The influence of some environmental factors during prenatal development on manifestation of non-metrical threshold skeletal traits in BALB/c inbred mice was studied. The factors under study were: introduction of metilthiouracil into the diet of pregnant females; injections of pregnant females with adrenocorticotropic or parathyreoid hormones; keeping the females at low temperatures (two regimens). Offsprings of the females treated were examined for twenty five skeletal characters using Berry-Sj?vold's method. Despite the fact that their body weights decreased in all experimental groups, phenetical distances between the treated and control groups were much smaller than those between different inbred strains. Reliability of genetical interpretation of interpopulational differences in non-metrical skeletal traits is higher for the characters which are not correlated with total body sizes. 相似文献
10.
We analyzed 4 meristic and 32 morphometric cranial traits of 612 adult specimens of spotted dolphins ( Stenella attenuata ) from the eastern tropical Pacific Ocean for sexual dimorphism. Eleven 5" latitude/longitude blocks with five or more of each sex were assessed with a two-way ANOVA for sex and geographic differences. Interaction between these two factors was found for six measurements, suggesting that the degree of sexual dimorphism varies geographically for a few characters (although in no discernible geographic pattern). Sexual dimorphism was demonstrated for 23 of the 36 characters, with differences ranging from 0.00 to 5.88 percent. Females characteristically had a longer rostrum, while males generally had larger skulls overall. In terms of number of characters, the extent of sexual dimorphism demonstrated for skulls of spotted dolphins goes considerably beyond that shown for any other small delphine. A discriminant function involving a combination of 10 characters enabled us to identify correctly the sex of more than 75 percent of the specimens. A procedure for correcting specimen measurements is outlined that would enable an investigator to combine male and female specimens in geographic variation studies. A term (zwitter) is proposed for use when referring to specimens where measurements have been corrected to take into account differences between the sexes. 相似文献
11.
R. J. Berry 《Journal of Zoology》1969,157(1):11-18
Twenty non-metrical variants are described in the skulls of Grey seals ( Halichoerus grypus ). Ten of these have been classified in samples of 47 skulls from Orkney and 18 from the Hebrides. The frequencies of one variant were "significantly" different ( P ≏1%) in the two samples. This result means that there is some genetical distinctiveness between the two samples and suggests a way of characterizing and hence comparing seal groups. 相似文献
12.
Silke Hauer 《Acta theriologica》2002,47(3):339-362
A sample of 1037 skulls of ottersLutra lutra (Linnaeus, 1758) from eastern Germany was analysed for inherent dental abnormalities. Deviations from the normal dental pattern
were found in 107 individuals. A total of 150 cases were classified in 5 categories of abnormality. In considering variations
from the normal number of teeth, supernumerary (polydonty, 1.7%) was more frequent than missing teeth (oligodonty, 0.9%).
In most cases, numerical variations were not connected with phylogenetic background. The most frequent variations were displacement
of teeth in the tooth row (6.0%) and deviations of the normal shape of teeth (3.3%). Variations of the local position of teeth
occurred in 2.6% of cases. None of these deviations showed significant sex-dependent differences. Furthermore, no regional
differences in the frequencies of these anomalies were noticed. Another 459 otters (822 cases) had accessory roots at P2,
P3, or P4. These characters were considered as non-metrical traits and used to study epigenetic regional differentiation.
The Mean Measure of Divergence segregated the Baltic coast from almost all other regions. Preliminary results of analysis
of Fluctuating Asymmetry are presented, using these traits to demonstrate the utility of dental deviations for estimating
influences on developmental stability. Generally, it can be stated that the dentition of otters is very stable. 相似文献
13.
C. Roberts 《Human Evolution》1987,2(6):539-545
A rare pronounced bar of bone on os innominata is described on three skeletons excavated from archaeological sites in Britain
of the Iron Age/Early Roman and Anglo-Saxon periods. Three possible causes are postulated for these ridges, pathological,
occupational and non-metrical variation. A non-metrical variation or occupationally induced trait appears to be the most likely
cause. 相似文献
14.
Inter and intra-population variation in morphological traits, such as body size and shape, provides important insights into the ecological importance of individual natural populations. The radiation of Diaptomid species (~400 species) has apparently produced little morphological differentiation other than those in secondary sexual characteristics, suggesting sexual, rather than ecological, selection has driven speciation. This evolutionary history suggests that species, and conspecific populations, would be ecologically redundant but recent work found contrasting ecosystem effects among both species and populations. This study provides the first quantification of shape variation among species, populations, and/or sexes (beyond taxonomic illustrations and body size measurements) to gain insight into the ecological differentiation of Diaptomids. Here we quantify the shape of five Diaptomid species (family Diaptomidae) from four populations each, using morphometric landmarks on the prosome, urosome, and antennae. We partition morphological variation among species, populations, and sexes, and test for phenotype-by-environment correlations to reveal possible functional consequences of shape variation. We found that intraspecific variation was 18-35% as large as interspecific variation across all measured traits. Interspecific variation in body size and relative antennae length, the two traits showing significant sexual dimorphism, were correlated with lake size and geographic location suggesting some niche differentiation between species. Observed relationships between intraspecific morphological variation and the environment suggest that divergent selection in contrasting lakes might contribute to shape differences among local populations, but confirming this requires further analyses. Our results show that although Diaptomid species differ in their reproductive traits, they also differ in other morphological traits that might indicate ecological differences among species and populations. 相似文献
15.
E Post N C Stenseth R Langvatn J M Fromentin 《Proceedings. Biological sciences / The Royal Society》1997,264(1386):1317
The variability of two fitness-related phenotypic traits (body weight and a mandibular skeletal ratio) was analysed among cohorts and age-classes of red deer in Norway. Phenotypic variation among cohorts was pronounced for calves, yearlings and reproductively mature adults. Fluctuations in cohort-specific mean body weights and skeletal ratios of adults correlated with global climatic variation in winter conditions influenced by the North Atlantic Oscillation while cohorts were in utero. Red deer born following warm winters were smaller than those born after cold winters, and this inter-cohort variability persisted into adulthood. Phenotypic variation among cohorts of red deer influenced by climate change may pose consequences for fitness of cohorts since body size and condition contribute to reproductive success and survival in male and female red deer. In particular, the recent trend of increasingly warm winters in northern Europe and Scandinavia may lead to reduced body size and fecundity of red deer, and perhaps other ungulates, in those areas. 相似文献
16.
YSTEIN WIIG 《Zoological Journal of the Linnean Society》1989,95(3):177-204
Craniometric variation in Norwegian wolverines was analysed using univariate and multivariate techniques. The wolverine skull seems to be full-grown after about 9 months in both sexes although some dimensions continued to grow at a slow rate after the first year. Size allometry was studied in skulls older than 11 months. Allometric coefficients were calculated from different methods. The multivariate allometric coefficients were found to reflect the same allometric patterns as were found from the reduced major axis and from the direction cosines of PCI, whereas the coefficients seem to be underestimated by the least-square regression method. Sexual dimorphism was found to be highly significant, males being the larger sex. The female skulls were found to be relatively broader and to have a relatively higher coronoid process than the male skulls. It seems that the females have a relatively stronger feeding apparatus than the males, which leads to less absolute differences in strength, as reflected in a very high degree of dietary overlap. Two discriminant functions were calculated which both classified the material into their correct sex with nearly 100% accuracy. Geographical variation between samples from Nordland and Finnmark counties were studied. No significant multivariate variation was found between the female skulls. The male variation was highly significant; the Nordland skulls seem to have longer carnassials than those from Finnmark. 相似文献
17.
The phenotype is a product of its phylogenetic history and its recent adaptation to local environments, but the relative importance of the two factors is controversial. We assessed the effects of diet, habitat, elevation, temperature, precipitation, body size, and mtDNA genetic divergence on shape variation in skulls, mandibles, and molars, structures that differ in their genetic and functional control. We asked whether these structures have adapted to environment to the same extent and whether they retain the same amount of phylogenetic signal. We studied these traits in intra- and interspecific populations of Eurasian marmots whose last common ancestor lived 2-5 million years ago. Path Analysis revealed that body size explained 10% of variation in skulls, 7% in mandibles, and 15% in molars. Local vegetation explained 7% of variation in skulls, 11% in mandibles, and 12% in molars. Dietary category explained 25% of variation in skulls, 11% in mandibles, and 9% in molars. Cyt b mtDNA divergence (phylogeny) explained 15% of variation in skulls, 7% in mandibles, and 5% in molars. Despite the percentages of phylogenetic variance, maximum-likelihood trees based on molar and skull shape recovered most phylogenetic groupings correctly, but mandible shape did not. The good performance of molars and skulls was probably due to different factors. Skulls are genetically and functionally more complicated than teeth, and they had more mathematically independent components of variation (5-6-in skulls compared to 3-in molars). The high proportion of diet-related variance was not enough to mask the phylogenetic signal. Molars had fewer independent components, but they also have less ecophenotypic variation and evolve more slowly, giving each component a proportionally stronger phylogenetic signal. Molars require larger samples for each operational taxonomic unit than the other structures because the proportion of within-taxon to between-taxon variation was higher. Good phylogenetic signal in quantitative skeletal morphology is likely to be found only when the taxa have a common ancestry no older than hundreds of thousands or millions of years (1% to 10% mtDNA divergence)--under these conditions skulls and molars provide stronger signal than mandibles. 相似文献
18.
ØYSTEIN WIIG F.L.S. 《Zoological Journal of the Linnean Society》1998,95(3):177-204
Craniometric variation in Norwegian wolverines was analysed using univariate and multivariate techniques. The wolverine skull seems to be full-grown after about 9 months in both sexes although some dimensions continued to grow at a slow rate after the first year. Size allometry was studied in skulls older than 11 months. Allometric coefficients were calculated from different methods. The multivariate allometric coefficients were found to reflect the same allometric patterns as were found from the reduced major axis and from the direction cosines of PCI, whereas the coefficients seem to be underestimated by the least-square regression method. Sexual dimorphism was found to be highly significant, males being the larger sex. The female skulls were found to be relatively broader and to have a relatively higher coronoid process than the male skulls. It seems that the females have a relatively stronger feeding apparatus than the males, which leads to less absolute differences in strength, as reflected in a very high degree of dietary overlap. Two discriminant functions were calculated which both classified the material into their correct sex with nearly 100% accuracy. Geographical variation between samples from Nordland and Finnmark counties were studied. No significant multivariate variation was found between the female skulls. The male variation was highly significant; the Nordland skulls seem to have longer carnassials than those from Finnmark. 相似文献
19.
A multivariate examination of cranial variation within and between European populations of Meles meles (L.) revealed that populations from Ireland, Great Britain, Norway, and the Slovak Republic could be differentiated both by cranial form and by the degree of sexual dimorphism exhibited. Irish material was characterized by low sexual dimorphism, particularly when compared to Slovak specimens. Badgers from the British Isles had larger skulls than other samples and were more similar to each other than they were to badgers from mainland Europe. Size played a greater role in differentiating samples of female badgers than it did in males. Significant variation occurred within the British Isles, with individual samples being highly differentiable. There was, however, little relationship between morphological similarity and geographic proximity. We contend that macrogeographical (between-country) variation in the species is primarily determined by historical factors and adaptation to current conditions, while microgeographic (within-country) variation is a result of selectively neutral processes. 相似文献
20.
ALEXEI V. ABRAMOV ANDREY YU PUZACHENKO ØYSTEIN WIIG 《Zoological Journal of the Linnean Society》2009,157(2):433-450
Morphometric variation in 30 craniometric characters of 465 skulls of the European badgers (Meles meles) from across Europe was analysed. Multivariate analyses revealed that the populations from Norway, Sweden, and Finland differ from other European populations in having smaller skulls. The analyses also revealed significant differences between the ‘south‐western Norwegian’ and ‘main Fennoscandian’ forms. On average, badgers from south‐west Norway were smaller than those of the remaining Fennoscandia. Morphological differences between the ‘south‐western Norwegian’ and ‘main Fennoscandian’ populations of M. meles suggest a possible in situ semisympatric divergence since the beginning of the Holocene warming, or a complex history of two groups involving at least two colonization routes. The small‐sized Scandinavian badgers may be close to the ancestral form that used to be widespread in Denmark and throughout Europe. The animals from south‐west Norway may instead be descendants of ancestors that were the first to penetrate the southern parts of the Scandinavian Peninsula. The ‘main Fennoscandian’ badgers are likely to have been the descendants of the second wave of recolonization of Scandinavia. Specifically, they might have colonized the Scandinavian Peninsula from the east after the last glaciation. 相似文献