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1.
现代人头骨面部某些特征的投影栅相位法测量研究   总被引:9,自引:0,他引:9  
用投影栅相位法 ,定量测量现代人面颅骨的一些项目 ,分析比较了中国南方、北方面骨的特点及中国与欧洲现代人面骨的差异 ,并探讨该方法在人类学研究领域应用的可行性和实用性。发现 :1 不论云南、欧洲头骨 ,性别差异主要集中在线距项目上 ,男性测量值大于女性。 2 华北头骨的中面宽、上面高及其指数、颧上颌高和内侧两眶宽指数大于云南头骨 ,中面部的扁平度小于云南头骨 ,颧骨额蝶突的前外侧面比云南头骨的要朝向前方。 3 中国云南、华北现代人头骨上面部的宽度小于欧洲现代人头骨 ,上面部扁平程度大于欧洲现代人头骨; 颧骨额蝶突的前外侧面比欧洲头骨更朝向前方。华北头骨上面部高度及其指数大于欧洲头骨; 云南头骨上面高及男性的上面高指数与欧洲头骨无差异 ,云南女性上面高指数大于欧洲头骨。我们认为投影栅相位法可作为传统测量方法的有益补充。  相似文献   

2.
The analysis of fluctuating asymmetry (FA) allows for estimating the influence of stress factors on human development and allows to evaluate resistance to stress. FA is often used as a marker of prenatal stress. The aim of this work is to estimate the symmetry of skulls from selected historic human populations and to analyse changes in their morphology which have taken place over centuries. The studied material consisted of two skull samples - a modern sample containing 82 skulls and a medieval sample of 77 skulls from Gródek on the Bug River. Radiographs were taken in postero-anterior (P-A) and base projections. Images were scanned and calibrated by means of MicroStation 95 Academic Edition software. Measurements of the skull images were used to estimate FA. All data were analysed statistically. The skulls in both samples showed asymmetry. The levels of FA varied in different skull regions. A high level of FA in the calvaria and a low asymmetry for the facial part of skull is characteristic of modern skulls. In medieval skulls these relations are inverted. The higher value of FA in modern skulls is an evidence of a higher level of developmental stress in the modern population as well as of its lesser abilities to resist stress.  相似文献   

3.
The ontogenetic sequence of cranial osteogenesis through adulthood is described in samples of newts from completely metamorphosing and partially neotenic populations. Cranial ossification proceeds in the same sequence in both samples. Seven stages of cranial development are described on the basis of conspicuous events that occur during ontogeny. These include four larval stages, metamorphs, efts, and adults. Neotenic adults have skulls that are metamorphosed completely and indistinguishable from the skulls of non-neotenic adults. Neoteny in these newts does not involve the skull and is limited to the postmetamorphic retention of some gill structures and, thus, is termed "limited neoteny." The evolution of limited neoteny in newts as a correlated response to the inhibition of land-drive behavior is discussed.  相似文献   

4.
The intrapopulation polymorphism of the pine marten (Martes martes L. 1758) was assessed on the basis of studying five samplings of skulls, three of which were collected on the same territory at different times. The geographical distance between the three sampling areas varied from 60 to 240 km. Study of the material using the phenetic (250 skulls), morphometric (151 skulls), and molecular genetic (21 skin samples) approaches allowed us to characterize the pine marten as a species with a low level of polymorphism. The genetic diversity (π = 0.0069 ± 0.0041 and H = 0.90 ± 0.039) is determined by ancient demographic processes that took place in the Pleistocene and Holocene and are related to the ice-age history of this species, its expansion, and the formation of the population on the territory under study. Low levels of phenetic (μ = 1.48 ± 0.056, h = 0.14 ± 0.033) and morphological (CV = 3.37 ± 0.41) diversity as well as a low level of sexual dimorphism (Isd = 9.4) indicate that the pine marten occupies a specific and relatively narrow ecological niche and is involved in weak competition with smaller mustelid species.  相似文献   

5.
In 1906, Lönnberg identified a native subspecies of Red deer Cervus elaphus scoticus L., in Britain after examining a sample of stags' skulls from Glenquoich (Inverness-shire, Scotland). In north-west England, it is commonly believed that "Red deer of indigenous stock have persisted in this area (Furness Fells, Lancashire, England) from time immemorial…" (Chard, 1966). Arrangements were made to introduce animals into a park within this area in 1970, which, in view of this local opinion, would have been the only Red deer within the district not of native origin. Therefore, it was thought desirable to examine all the stocks of wild or feral Red deer in Britain and to determine which, if any, of them could be considered native and thus deserving of special measures to ensure their survival.
After examining samples of skulls, using multivariate analysis, it appeared that, within the limits of the material representing the various subspecies of the world, there was little support for the concept of subspeciation in Red deer. In Great Britain, however, there appeared to be two distinct forms of Red deer leading a free existence, one presumed to be native and the other to be of park derivation. Visually, the differences were indetectable and could be demonstrated only by discriminant analyses.  相似文献   

6.
Measurements of the external opening of the tear duct (naso-lachrymal canal) of skulls of American colored males and white males indicate larger apertures among the former at corresponding ages. Duct length is somewhat shorter among colored males. In both racial samples the older skulls have slightly larger apertures than those under 40. A sample of white female skulls corroborates this, and manifests smaller average size than the white male skulls at ages below 50 whereas older skulls reveal no sex difference. The race difference in aperture size among male skulls is highly significant statistically and may reflect ecological adaptation.  相似文献   

7.
Harbor seals (Phoca vitulina) inhabit the seas surrounding Denmark and are an important top predator in the marine food chain. This trophic position exposes them to environmental contaminants with disease epidemics and hunting being additional threats to this population. It is therefore important to study how environmental pollution at the current order of magnitude affects the health of the population. Earlier studies have shown that occurrence of periodontitis could be linked to the amount of pollution the seals were subjected to. In order to investigate this further, 380 skulls and 141 mandibles of harbor seals (Phoca vitulina) from the Wadden Sea, the Limfjord, and Kattegat collected during the period 1970–2014 were examined. The skulls were examined for pathological lesions. The Hounsfield Units (HU) which are correlated to the bone mineral density (BMD) were measured in a subsample (n = 34) using CT scans. The macroscopic examination revealed (with the exception of the Swedish part of Kattegat) a significant increase of pathological lesions over the study period of 1981–2014. The examination of HU showed that median HU measured at multiple sites was highest in the healthy skulls compared to the skulls with one or more of the lesions. A discriminant analysis allowed high discriminatory capacity to separate healthy skulls from the skulls with pathologies, simply by the utilization of the HU data. Former studies of BMD in marine mammals have shown that exposure to environmental chemicals alter BMD and cause periodontitis. The present study, based on temporal and spatial trends in BMD, confirms the results of previous studies.  相似文献   

8.
A worldwide survey of babirusa skulls curated in museum and private collections located 431 that were from adult males and had retained at least one maxillary canine tooth. Eighty-three of these skulls were identified as exhibiting aberrant maxillary canine tooth growth. Twenty-four of the skulls represented babirusa from Buru and the Sula Islands, and forty-five skulls represented babirusa from Sulawesi and the Togian Islands. The remaining series of fourteen babirusa skulls originally came from zoo animals. Fifteen skulls showed anomalous alveolar and tooth rotation in a median plane. Twenty-nine skulls had maxillary canine teeth that did not grow symmetrically towards the median plane of the cranium. Fourteen skulls showed evidence that the tips of one or both maxillary canine teeth had eroded the nasal bones. Twenty-one skulls had maxillary canine teeth that had eroded the frontal bones. The teeth of two skulls had eroded a parietal bone. One skull had two maxillary canines arising from an adjacent pair of alveoli on the left side of the cranium. Three skulls exhibited alveoli with no formed maxillary canine teeth in them. Analysis suggested that approximately 12% of the adult male babirusa in the wild experience erosion of the cranial bony tissues as a result of maxillary canine tooth growth. There was no skeletal evidence that maxillary canine teeth penetrate the eye.  相似文献   

9.
The cranial morphology of Early Holocene American human samples is characterized by a long and narrow cranial vault, whereas more recent samples exhibit a shorter and wider cranial vault. Two hypotheses have been proposed to account for the morphological differences between early and late‐American samples: (a) the migratory hypothesis that suggests that the morphological variation between early and late American samples was the result of a variable number of migratory waves; and (b) the local diversification hypothesis, that is, the morphological differences between early and late American samples were mainly generated by local, random (genetic drift), and nonrandom factors (selection and phenotypic plasticity). We present the first craniometric study of three early skulls from the Argentinean Pampas, dated ~8,000 cal. years BP (Arroyo Seco 2, Chocorí, and La Tigra), and one associated with mega‐faunal remains (Fontezuelas skull). In addition, we studied several Late Holocene samples. We show that the skulls from the Argentinean Pampas are morphologically similar to other Early Holocene American skulls (i.e., Lagoa Santa from Brazil, Tequendama, Checua, and Aguazuque from Colombia, Lauricocha from Peru, and early Mexicans) that exhibit long and narrow cranial vaults. These samples differ from the Late Holocene American samples that exhibit a shorter and wider cranial vault. Our results underscore the important differences in cranial morphology between early and late‐American samples. However, we emphasize the need for further studies to discuss alternative hypotheses regarding such differences. Am J Phys Anthropol 143:298–305, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

10.
Previous cephalometric studies of occlusofacial angular and metric data show small variability within and between population samples of Caucasian children and adults. Comparable results were obtained by use of standardized X-ray cephalometry and direct craniometric measurements of skulls of mature specimens of Alouatta caraya and Cebus capucinus. These data measure facial and occlusofacial form and form relationships. Identical measuring techniques are applied to compare data derived from headplates of 19 young adult American Caucasians and 19 articulated Hindu skulls of mature individuals. The data are expanded to include measurements that relate symphyseal form to occlusal and nasomaxillary structure. The facial plane and an "internal" facial plane (nasion to a point tangential to the superior genial tubercles) straddle the mandibular symphysis. The angles they form at nasion and at their intersections with the maxillary occlusal plane were derived and statistically analyzed. The occlusal plane intersect angles show small absolute variability and are not significantly different (P greater than .05) in the two groups. The nasion plane angles are significantly different (P less than .025), reflecting sample differences in facial height. Linear measurements confirm a considerably larger dentoalveolar prognathism in the Hindu group. Data derived from the geometrically averaged tracings of Bjork, Broadbent, Sassouni, and Solow provide further evidence of occlusofacial form commonality. These shared phyletically conservative traits are evidence of highly integrated morphological adaptations for the attainment, maintenance, and functioning of the species-wide pattern of precisely fitting complementary crowns and crown parts that constitute the dental occlusion.  相似文献   

11.
Facial width-to-height ratio (FWHR), defined as the width of the face divided by the upper facial height, is a cue to behaviour. Explanations for this link often involve the idea that FWHR is sexually dimorphic, resulting from intersexual selection pressures. However, few studies have considered sexual dimorphism in skulls since the original paper on this topic, and it is possible that different explanations may be required if faces show sex differences but skulls do not. Here, meta-analyses of skulls found that men did have larger FWHR than women, although this effect was small. However, after categorising samples by ethnicity and geographical origin, meta-analyses only found evidence of sex differences in East Asians, and again, this effect was small. A re-analysis of previous studies after excluding skull samples found little evidence of sexual dimorphism in faces. Again, considering ethnicities separately, I found no differences for White samples but a medium-sized effect with East Asians, although this was not statistically significant with only three samples. Taken together, I found no reason to consider FWHR as a sexually dimorphic measure in skulls or faces, at least not universally, and so accounts based upon this assumption need rethinking if researchers are to explain the relationship between FWHR and behaviour.  相似文献   

12.
《Plains anthropologist》2013,58(85):249-253
Abstract

Comparison of the populations of four Panhandle Aspect sites (Alibates, Antelope Creek, Matthews Ranch, Footprint) using 28 non-metric traits of the skulls indicates generally close similarity among them, but the Panhandle groups show little similarity to Upper Republican. Antelope Creek and Matthews Ranch show some resemblance to the Fort Coffee skulls of the Fulton Aspect. The same two Panhandle site samples also resemble the Washita River people. Footpnnt is even more similar to Washita River.  相似文献   

13.
The frontal sinuses of 143 Eskimo skulls from two sites in the Hudson Bay region of Canada were examined radiographically. No between-site or sex differences were noted in the size of the sinuses. On average, the sinuses are small and often bilaterally absent. The Canadian samples have smaller sinuses than reported for Alaskan Eskimos or American Indian groups.  相似文献   

14.

Background and Purpose

Transcranial near-infrared laser therapy (TLT) is a promising and novel method to promote neuroprotection and clinical improvement in both acute and chronic neurodegenerative diseases such as acute ischemic stroke (AIS), traumatic brain injury (TBI), and Alzheimer’s disease (AD) patients based upon efficacy in translational animal models. However, there is limited information in the peer-reviewed literature pertaining to transcranial near-infrared laser transmission (NILT) profiles in various species. Thus, in the present study we systematically evaluated NILT characteristics through the skull of 4 different species: mouse, rat, rabbit and human.

Results

Using dehydrated skulls from 3 animal species, using a wavelength of 800nm and a surface power density of 700 mW/cm2, NILT decreased from 40.10% (mouse) to 21.24% (rat) to 11.36% (rabbit) as skull thickness measured at bregma increased from 0.44 mm in mouse to 0.83 mm in rat and then 2.11 mm in rabbit. NILT also significantly increased (p<0.05) when animal skulls were hydrated (i.e. compared to dehydrated); but there was no measurable change in thickness due to hydration.In human calvaria, where mean thickness ranged from 7.19 mm at bregma to 5.91 mm in the parietal skull, only 4.18% and 4.24% of applied near-infrared light was transmitted through the skull. There was a slight (9.2-13.4%), but insignificant effect of hydration state on NILT transmission of human skulls, but there was a significant positive correlation between NILT and thickness at bregma and parietal skull, in both hydrated and dehydrated states.

Conclusion

This is the first systematic study to demonstrate differential NILT through the skulls of 4 different species; with an inverse relationship between NILT and skull thickness. With animal skulls, transmission profiles are dependent upon the hydration state of the skull, with significantly greater penetration through hydrated skulls compared to dehydrated skulls. Using human skulls, we demonstrate a significant correlation between thickness and penetration, but there was no correlation with skull density. The results suggest that TLT should be optimized in animals using novel approaches incorporating human skull characteristics, because of significant variance of NILT profiles directly related to skull thickness.  相似文献   

15.
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   

16.
The elemental composition of both healthy and eroded cetacean skulls associated with nematode infections was evaluated. A total of 27 samples of eroded and non-eroded prepared museum cetacean skulls were characterised by elemental (CHN), X-ray fluorescence, and X-ray diffraction methods. The inorganic composition and crystal line structure (hydroxylapatite-like minerals) were similar for both types of skull samples, but the CHN values clearly differed. The results suggest that the carbon-rich fraction is lost in eroded areas, probably as a result of glycosaminoglycan-degrading Crassicauda enzymes.  相似文献   

17.
In this study we estimate sex and population affinity of Gravettian Predmostí (P) skulls using linear and geometric discriminant analysis (DA), and compare them with results of 2D geometric morphometrics (GM). We used the measurements of P3 and P9 males, P4 and P10 females, as originally estimated by Matiegka (1934), as well as two databases--the recent skull database of Howells and the fossil data of Henke. DA classifies the P skulls as robust and belonging to the "male" region, loosing the sensitivity of inter-population differences influenced by size factor. That is why this approach could not be applied. The geographic inter-population differences according to DA do not define P skull shapes as extreme. The influence of geographic variability could be stronger than the inter-sexual differences. Despite the chronological differences between databases and Gravettian skulls, these differences are a component of regional inter-population variability. According to our results, GM is more successful methodological approach than DA. Our previous sex estimation of P skulls with help of GM is completely in accordance with the classical morphoscopic estimation. However, an appropriate reference database is necessary in both the GM and DA approaches. For the sexing of skull with unknown population affinity, and with absence of appropriate reference database, we suggest to use the application of more subjective visual scoring methods.  相似文献   

18.
Using a total of 43 craneological data obtained from any of 73 vicugna and 25 alpaca skulls, three problems were analyzed:
  • Identification of skulls

  • Taxonomic situation of the vicugna

  • Origin of the alpaca.

For rapid identification of New World cameloid skulls it is recommended to use the condilobasal length, the length to heigth ratio and the presence of the Fissura nasolacrimalis.

Some characteristics of the skulls considered essential for the evaluation of domestication processes exclude the vicugna from the alpaca's ancestors.  相似文献   

19.
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   

20.
Historical samples, like tanned hides and trophy skulls, can be extremely important for genetic studies of endangered or elusive species. Selection of a sampling protocol that is likely to provide sufficient amount and quality of DNA with a minimum damage to the original specimen is often critical for a success of the study. We investigated microsatellite genotyping success of DNA isolated from three different types of Eurasian lynx historical samples. We analysed a total of 20 microsatellite loci in 106 historical samples from the endangered Dinaric lynx population, established from re-introduction of three pairs of lynx in 1973 from Slovakian Carpathians. Of the three tested sample types, turbinal bone and septum from the nasal cavity of the trophy skulls had the lowest percentage of samples successfully genotyped for all 20 microsatellite loci. Footpad samples, collected using a cork drill, exhibited better results in polymerase chain reaction amplification and genotyping than samples of footpad epidermis cut with a scalpel. We report simple and efficient sampling protocols, which could be widely applied for future studies utilizing historical samples.  相似文献   

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