Elastic properties of human supraorbital and mandibular bone

Elastic constants, including the elastic modulus, the shear modulus, and Poisson's ratio, were measured on human craniofacial bone specimens obtained from the supraorbital region and the buccal surfaces of the mandibles of unembalmed cadavers. Constants were determined using an ultrasonic wave technique in three directions relative to the surface of each sample: 1) normal, 2) tangential, and 3) longitudinal. Statistical analysis of these elastic constants indicated that significant differences in the relative proportions of elastic properties existed between the regions. Bone from the mandible along its longitudinal axis was stiffer than bone from the supraorbital region. Directional differences in both locations demonstrated that cranial bone was not elastically isotropic. It is suggested that differences in elastic properties correspond to regional differences in function. © 1993 Wiley-Liss, Inc.     

Multiple discriminant function analysis of sex and race in the postcranial skeleton

Terry Collection femora and innominates of 260 American Whites and Blacks (65 males and 65 females of each race) were analyzed by multiple discriminant function analysis. A stepwise procedure produced three optimal discriminant functions using 15 of our 32 measurements. These functions correctly identified 95% of the sample. The first two-one for sex and one for race-are statistically and biologically significant and form the basis of our analysis. The sexing function manifested both size and shape elements. Prominent among the former was joint size--acetabular diameter and epicondylar diameter of the femur. The shape elements included form of the greater sciatic notch and of the inferomedial aspect of the pubic body. The racing function highlighted a pattern of greater innominate dimensions, exclusive of the acetabular joint, in Whites. This was in contrast to the greater length of the Black femur. Overall, the function seems to express the established differences between the races in the ratio of lower limb length to torso length. While these functions have been applied successfully to forensic cases with confirmed identifications, questions regarding the breadth of applicability of discriminant functions make it desirable to validate our results on new material from the Terry and other collections.     

Technical note: A blind test of mandibular ramus flexure as a morphologic indicator of sexual dimorphism in the human skeleton

Loth and Henneberg (1996, Am. J. Phys. Anthropol. 99:473–487) identified a single morphological feature of the mandible, the presence or absence of a distinct flexure or angulation of the posterior margin of the mandibular ramus at the level of the occlusal plane, which appears to be an extraordinarily accurate predictor of sex. Using only this feature, Loth and Henneberg were able to predict sex with 94% accuracy in a large sample of mandibles. In this article, we report the results of a blind test of mandibular ramus flexure as a predictor of sex. In our blind test, only 62.5% of the mandibles were correctly sexed, and virtually identical results were obtained when the same sample of mandibles was examined by a second observer. Overall, our results demonstrate that: 1) the association between ramus flexure and sex is weak; 2) the predictive accuracy of Loth and Henneberg's method is better than chance for only one sex, males; and 3) the method is based on a trait that cannot be reliably or consistently identified. Am J Phys Anthropol 107:363–366, 1998 © 1998 Wiley-Liss, Inc.     

Cephalometric study of elderly with nearly intact dental arches

Objective: The purpose of this study was to investigate the craniofacial morphology of elderly people with many remaining teeth using cephalometric analysis. Subjects and methods: The subjects were 30 Japanese elderly who participated in the ‘8020 campaign 2001’ in Bunkyo Ward, Tokyo, organised by The Dental Association of Tokyo, as well as 30 Japanese young adults with normal occlusion. Lateral cephalograms of all subjects were analysed using the Coben method. Results: In the female elderly group, the lower face depth was smaller than in the younger adults. In the male elderly group, the height and depth of both the total face and the lower face were longer than in the younger group. In comparing the 8020 achievers with the younger group, the proportion of the lower facial height was greater than the upper facial height, and this finding was more pronounced in women than in men. Conclusion: For the lateral facial pattern of the elderly, a reduction of lower facial height because of tooth occlusal reduction was not apparent. It was clear that there are age differences for males and females; in addition, differences in the total face and lower face area of the elderly group were due to their having many remaining teeth over a long time period. Also, these changes were more apparent in women than in men, and it is clear that there is a male–female difference in ageing.     

Mandibular ramus flexure: A new morphologic indicator of sexual dimorphism in the human skeleton

In the skeleton, male and female characteristics lie along a continuum of morphologic configurations and metric values. Size alone is not the best indicator of sex. In contrast, morphologic differences that arise from genetically sex-linked growth and development allow better separation of the sexes. This study presents a new morphologic indicator of sexual dimorphism in the human mandible. A sample of 300 mandibles from adults of known sex primarily from the Dart collection was analyzed. Of these, 100 were found to have obvious bony pathologies and/or excessive tooth loss (“pathologic” sample). Thus, the normative sample consisted of 200 individuals (116 males, 84 females). Examination of morphologic features led to the discovery of a distinct angulation of the posterior border of the mandibular ramus at the level of the occlusal surface of the molars in adult males. Flexure appears to be a male developmental trait because it is only manifest consistently after adolescence. In most females, the posterior border of the ramus retained the straight juvenile shape. If flexure was noted, it was found to occur either at a higher point near the neck of the condyle or lower in association with gonial prominence or eversion. In the normative sample, overall prediction accuracy from ramus shape was 99%. When the “pathologic” sample was analyzed separately, 91.0% were correctly diagnosed. Because the African samples were overwhelmingly black, this trait was also tested on American samples (N = 247) of whites (N = 85), Amerinds (N = 66), and blacks (N = 96) that included a mix of healthy individuals and those with extensive tooth loss and evidence of pathology. The results were nearly identical to those of the “pathologic” African sample, with accuracies ranging from about 91% in whites and blacks to over 92% in Amerinds. Total accuracy for all African and American samples combined (N = 547) is 94.2%. In conclusion, at 99%, sexing from the shape of the ramus of a healthy mandible is on a par with accuracy attainable from a complete pelvis. Moreover, there is no record that any other single morphologic or metric indicator of sex (that has been quantified from the adult skeleton) surpasses the overall accuracy attained from the more representative mixed sample produced by combining all groups assessed in this study. The usefulness of this trait is enhanced by the survivability of the mandible and the fact that preliminary investigations show that the trait is clearly evident in fossil hominids. © 1996 Wiley-Liss, Inc.     

Sexual dimorphism in four species of rockfish genusSebastes (Scorpaenidae)

Synopsis Sexual dimorphisms, and factors influencing the evolution of these differences, have been investigated for four species of rockfish:Sebastes melanops, S. flavidus, S. mystinus, andS. serranoides. These four species, which have similar ecology, tend to aggregate by species with males and females staying together throughout the year. In all four species adult females reach larger sizes than males, which probably relates to their role in reproduction. The number of eggs produced increases with size, so that natural selection has favored larger females. It appears males were subjected to different selective pressures than females. It was more advantageous for males to mature quickly, to become reproductive, than to expend energy on growth. Other sexually dimorphic features include larger eyes in males of all four species and longer pectoral fin rays in males of the three piscivorous species:S. melanops, S. flavidus, andS. serranoides. The larger pectoral fins may permit smaller males to coexist with females by increasing acceleration and, together with the proportionately larger eye, enable the male to compete successfully with the female to capture elusive prey (the latter not necessarily useful for the planktivoreS. mystinus). Since the size of the eye is equivalent in both sexes of the same age, visual perception should be comparable for both sexes.     

First report of Culicoides boyi (Diptera: Ceratopogonidae) in France

Culicoides boyi Nielsen, Kristensen & Pape 2015 (Diptera: Ceratopogonidae), described in Denmark in 2015, is reported in France. This species is closely related to Culicoides pulicaris (Linnaeus 1758) and can only be distinguished from this species by a subtle variation in spot wing pattern and by calculation of maxillary palpal ratio.     

Growth and sexual dimorphism in a population of hybrid macaques

Growth and sexual dimorphism have long been the focus of investigation for researchers interested in the life history and socioecology of nonhuman primates. Previous research has shown that sex differences in the duration of growth, or bimaturism, are primarily responsible for the sexual dimorphism observed in anthropoid primates with multimale–multifemale social structure, such as macaques. The present study investigates sex differences in patterns of craniofacial and somatometric growth relative to head and body size and relative to dental development in a population of hybrid macaques (Cercopithecidae: Macaca ) from Sulawesi, Indonesia. How these patterns may contribute to sexual dimorphism in this hybrid population is also examined. The results of the study suggest that there is no substantial effect on the levels of sexual dimorphism associated with hybridization in these macaques. Although sex differences in patterns of size-related, or allometric, growth patterns play a significant role in the development of sexual dimorphism for some cranial dimensions in these hybrids, bimaturism seems to be the primary component in the ontogeny of sexual dimorphism in this hybrid population. The observed levels of hybrid dimorphism and the predominant ontogenetic pattern of bimaturism characterized by prolonged male growth are consistent with previously published reports on dimorphism and growth in other cercopithecine primates.     

Sex determination using discriminant function analysis in Indigenous (Kurubas) children and adolescents of Coorg,Karnataka, India: A lateral cephalometric study

Aim: To test the validity of sex discrimination using lateral cephalometric radiograph and discriminant function analysis in Indigenous (Kuruba) children and adolescents of Coorg, Karnataka, India. Methods and materials: Six hundred and sixteen lateral cephalograms of 380 male and 236 females of age ranging from 6.5 to 18 years of Indigenous population of Coorg, Karnataka, India called Kurubas having a normal occlusion were included in the study. Lateral cephalograms were obtained in a standard position with teeth in centric occlusion and lips relaxed. Each radiograph was traced and cephalometric landmarks were measured using digital calliper. Calculations of 24 cephalometric measurements were performed. Results: Males exhibited significantly greater mean angular and linear cephalometric measurements as compared to females (p < 0.05) (Table 5). Also, significant differences (p < 0.05) were observed in all the variables according to age (Table 6). Out of 24 variables, only ULTc predicts the gender. The reliability of the derived discriminant function was assessed among study subjects; 100% of males and females were recognized correctly. Conclusion: The final outcome of this study validates the existence of sexual dimorphism in the skeleton as early as 6.5 years of age. There is a need for further research to determine other landmarks that can help in sex determination and norms for Indigenous (Kuruba) population and also other Indigenous population of Coorg, Karnataka, India.     

Sexually dimorphic mandibular morphology in the first few years of life

Sex differences in the youngest skeletons are very subtle, and any method that can separate males and females significantly better than chance will be of value. Compounding the problem is a paucity of immature skeletons of documented age and sex. In 1992, S.R.L. examined 62 juvenile mandibles of white and black South Africans of known age and sex (from birth to 19 years) from the Dart Collection to determine if the sexes could be differentiated by morphologic traits. By age 6 years, adult chin shapes were already recognizable. Prior to that age, differences were observed in the shape of the inferior border of the symphysis and outline of the body. The male chin base extends steeply downward relative to the adjacent body, coming to a point or squaring off at the symphysis. In females, the symphysis descends gradually to a more rounded base, and even when pointed, the transition is not abrupt. On the outer border of the corpus, the sides diverge sharply to form a \_/ shape from a roughly horizontal anterior region in males, while the female contour is rounded, reflecting the smoothly curved transition from front to sides. These traits were manifest from the eruption of the central incisors until about 4 years of age. The features were tested on all 19 Dart Collection mandibles in that age range. Average accuracy for three different testers was 81%, and males were consistently identified more accurately than females. This new method was then tested on a known sex sample of 11 individuals from 0 to 7 years of age. These included CT scans of 9 French children and the remains of 2 South African black forensic cases. Sexing accuracy was 82% (9/11). The only two missexed cases were both female and over age 6 years. In conclusion, the results of this study indicate that it is possible to determine the sex of very young mandibles. The new sexually dimorphic morphologic configurations introduced here have demonstrated repeatable discrimination with the highest level of accuracy (81%) reported and tested for this age group. Preliminary research indicates that both the male and female shapes are clearly recognizable in archaeologic and premodern hominids as well as chimpanzees.     

Anthropometric analysis of the face in hypohidrotic ectodermal dysplasia: a family study

Sixteen individuals with hypohidrotic ectodermal dysplasia (HED) were compared to normal standards as well as to 16 unaffected family members by using a series of 20 anthropometric measurements of the head and face. Individuals with HED were generally smaller than normal controls or their unaffected relatives. However, this size reduction was not uniform. Instead, it was most evident in the anterior-posterior dimensions of the lower two-thirds of the face, in facial height, and in the size of the ears, nose, and mouth. A stepwise discriminant function analysis indicated that a function constructed from four variables (depth of the lower face, width of the nose, mandibular arc, and total facial height) could accurately classify 96.7% of the 32 individuals in the combined sample of affected and unaffected individuals. These findings demonstrated that the face of individuals with HED is unique and can be useful in its diagnosis. Additional studies are needed to determine if similar-though-less-pronounced facial abnormalities can be used to detect minimally affected gene carriers of this presumably X-linked condition.     

基于三维人脸模型及人工测量数据分析现代中国人群面部表型的性别差异

传统体质人类学研究中的样本采集方法是手工测量以及肉眼观察,采集过程中会存在较大的主观性,易产生误差,同时在采集大样本时费时费力。近年来,三维摄像系统被越来越多的应用于人脸分析,其优势是快速高效和准确,并且涵盖了传统测量方法无法精确获取的表型特征信息,可以更加细化地分析人脸表型特征和特征之间的相互关系。本研究探索性地基于三维人脸模型图像,利用曲率和邻域信息的点筛查方法定位了面部的一些关键测量点,建立一套简单、有效、准确率较高的三维人脸模型图像关键点定位方法,能较准确地定位98%以上的眼内角点和鼻尖点,并在此基础上确定了鼻根点、鼻下点、左右鼻翼点和鼻翼外侧最低点等其他面部关键点。并且还提出了在三维人脸模型图像基础上量化部分面部观察类表型特征,如鼻侧深度、鼻根高度、面部扁平度等,尝试性地将这些观察类性状转化为能够测量的性状,建立了一套可以计算的描述方法,具有一定的创新性。本研究还结合三维人脸模型提取数据和人工测量数据,探讨了现代中国人群(以江淮汉族为例)面部表型特征的性别差异,发现大多数面部表型特征在现代中国人群中都存在明显的男女性别差异,鼻侧深度、鼻根高度、面部扁平度的性别差异最为显著,其...     

太行山猕猴肩胛骨和肱骨的性别判别

测量了 2 6例 (♀ 1 6,♂ 1 0 )成年太行山猕猴肩胛骨和肱骨的 1 5项变量。通过运用SPSS1 0 0单因子方差分析 ,结果显示 ,有 9项变量在两性间达到了显著差异水平 ;采用多变量判别分析方法对有关变量建立判别函数 ,结果显示 ,采用强迫引入法和逐步判别法 ,判别正确率分别为 1 0 0 0 0 %和 92 3 0 %;运用主成分分析 ,进一步说明肩胛骨和肱骨在性别判别中有一定的作用     

海洋活化石——鲎的研究进展

海洋活化石——鲎（hòu）是十分宝贵的自然资源,在科研、经济、生态等方面都有着不可估量的价值。鲎作为古老的海洋底栖动物被过度捕捞,现已到了枯竭的程度,2021年2月,我国《国家重点保护野生动物名录》正式更新和发布,我国海域的中国鲎和圆尾鲎被列为国家二级保护动物。为推动鲎研究和有效制定实施鲎资源的保护措施,本文主要从鲎的生物学研究、资源利用和生态保护三个方面入手,瞄准鲎的分类学问题、鲎的生物学前沿问题包括神经系统、视觉系统、消化系统、循环系统、生殖与发育和共附生微生物等、生态保护现状以及存在的问题等方面国内外的研究进展进行综述,明确研究重点和难点的同时,扩大对鲎的认知。     

太行山猕猴掌骨和蹠骨长度的性别判别

研究太行山猕猴掌骨和蹠骨长度的性别差异。对24例掌骨和26例蹠骨的长度变量进行测量, 用SPSS13.0统计软件进行单因素方差分析和多变量判别分析。结果表明: 掌骨和蹠骨的长度变量在性别之间有极显著性差异(P＜0.00)。各掌骨和各骨的长度顺序在侧别之间和性别之间有一定差异, 但是尚未达到统计学意义( P> 0.05) 。用全模型法和逐步判别法根据长度变量分别建立性别判别函数, 其性别正确判别率掌骨分别为91.7%和93.8%, 而蹠骨的性别判别率为84.6%。表明猕猴掌骨和蹠骨长度性别之间存在明显性差。使用掌骨和蹠骨长度变量进行性别鉴定有一定理论价值和应用价值。     

Spectrographic analysis of trace elements in archaeological skeletal material from Florida: a preliminary report

Technological advances have resulted in the development of an additional approach to determining the dietary practices of prehistoric populations. Bones are known to retain certain trace elements, the analysis of which should yield valuable clues to subsistence. Since there has never been a study of this nature attempted on Indian remains in Florida, a qualitative trace element analysis, using an optical emission spectrograph, was made of bone samples from indigenous populations representing both inland and coastal environments in this region. Results of this study showed that magnesium was present in all samples, copper was present in nearly half the samples, and manganese and zinc were not detected. Thus, although the diets of these groups may have varied, the trace element content did not reflect significant differences as have been reported for other types of analyses on Indian populations from diverse geographic regions.     

A craniofacial morphological study of a population of northern Greek children

689 boys and 644 girls of a northern Greek children population have been studied concerning the head and face shape by means of principal component analysis. From the morphological patterns show a homogenic population with small shape differences due mainly to vertical and ear variables. Size differences appear to be responsible for the variability of the population.     

Zonal distribution and population biology of Ilyoplax frater (Brachyura: Ocypodoidea: Dotillidae) in a coastal mudflat of Pakistan

Zonal distribution and population biology of Ilyoplax frater were studied in a mangrove mudflat area of Pakistan. The crabs were collected from Korangi creek through transect and quadrat method from low tide level to high tide level. Two transects were delimited in a mangrove area of Korangi creek (24°79'N/ 67°20'E). On each transect, three 0.25 m quadrats were sampled at three tidal levels on a monthly basis during low tide periods from March 2001 to February 2002. A total of 1124 crabs were obtained, of w...     

Occurrence of an adult Atlantic salmon in the River Rhône, France

A large salmonid was caught in the commercial fisheries in the River Rhône (Mediterranean basin, France). Using morphological criteria and DNA analysis, the fish has been identified as an adult Atlantic Salmon Salmo salar .