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1.
Here, we describe the first skeletal remains of Notostylops recovered from middle Eocene levels of the Sarmiento Formation, Patagonia, Argentina. The remains include two teeth of Notostylops murinus, the axis, vertebral bodies, a rib, a left humerus, both radii, two metapodials, two phalanges, the pelvis, a right femur, a right calcaneus and several broken bones. Radial bones are not fused to ulnas, and are shorter than the humerus, very generalized, with an oval head, a marked neck and a radial tubercle. The humerus and the femur show pronounced insertion structures. Our analysis suggests that the appendicular skeleton of Notostylops is too generalized and shares several features with that of terrestrial rodents as Sciuridae. Unlike the appendicular skeletons of cursorial or saltatorial mammals, which restrict mobility, the skeleton of Notostylops indicates the ability to make a variety of different movements, as would be expected for terrestrial, fossorial or arboreal mammals. This skeleton gives new information about the locomotor behaviour of notoungulates, particularly in their basal forms. The results will also allow the identification of isolated notoungulate bones and raise questions about the previous taxonomic assignment of postcrania to Pleurostylodon.  相似文献   

2.
在陕甘宁盆地东北缘二马营组发现的两种假鳄类,经鉴定均属Euparkeridae。其中之一与Euparkeria较相近;根据肩胛骨、肱骨和骨质背板等的显著不同,定名为侨家梁哈拉寨鳄(Halazhaisuchus qiaoensis),新属、新种。依据骨髂形态,另一标本归入世鲁番鳄属(Turfanosuchus),取名沙圪堵吐鲁番鳄(Turfanosuchus shageduensis)、新种。  相似文献   

3.
4.
记述了四川会理下侏罗统益门组的蜥脚类化石。经研究,将化石归于马门溪龙科,建立新属新种何氏通安龙Tonganosaurus hei gen.et sp.nov.。通安龙具有进步蜥脚类的特点:颈椎细长、荐前椎发育侧凹、前肢较长,为后肢的0.80等;同时,通安龙也具有原始蜥脚类的特点:脊椎骨组织坚实不中空、肱骨和股骨骨干粗而圆。从国内外已有的资料看,原始蜥脚类主要发现于侏罗纪早期,而进步蜥脚类则主要发现于侏罗纪中晚期。由于通安龙兼具原始蜥脚类和进步蜥脚类的特点,且时代为早侏罗世,因此,通安龙化石材料的发现对中国西南地区早期蜥脚类的系统演化研究具有重要的意义。  相似文献   

5.
目的:研究道路交通事故卡车与卡车前部碰撞驾乘人员损伤特征,分析比较驾乘人员的损伤及损伤分布特点。方法:应用统计学方法对2001年-2010年昆明地区卡车与卡车200例前部碰撞人员损伤的法医学鉴定资料进行系统分析性研究。结果:1.驾驶员易发生损伤的部位是下肢、头颈部,其次为胸、腹部损伤。驾驶员易发生右下肢的损伤及骨折。驾驶员易发生颅骨骨折和肋骨骨折。2.前排乘车人员易发生损伤的部位是上肢、头颈部,其次为下肢,而胸腹部损伤较少见。前排乘车人员易发生上肢的损伤及双侧尺桡骨的骨折。前排乘车人员左侧头颈部受伤的几率大于驾驶员的相对部位。前排乘车人员易发生右肱骨骨折。结论:1.与前排乘车人相比,驾驶员易造成胸部、腹部及盆部、右侧下肢的损伤及右股骨胫腓骨的骨折,发生双侧上肢的体表损伤及尺桡骨骨折均明显少。在身体体表出现胸部、腹部及盆部多部位连续的损伤,有助于提高认定卡车驾驶员的准确性。2.与驾驶员相比,前排乘车人易形成左侧头颈部的损伤,上肢双侧尺桡骨骨折,右侧肱骨的骨折。当损伤位于身体左侧头颈部且有右侧肱骨的骨折,有助于提高认定卡车前排乘车人的准确性。  相似文献   

6.
In April–May 1983, the late A.R. Hughes and his field team recovered more than 40 bone fragments and teeth from a single solution pocket of the Sterkfontein Formation. After preparation and reconstruction by JMC, it was recognised that these fragments represent a single juvenile individual (Stw 151), consisting of more than 40 cranial and dental parts, with mixed dentition. It constitutes the most complete set of jaws and teeth of an early hominid child since the Taung child was recovered in 1924. In this paper, the morphological and metrical features of the individual teeth are described. The other associated skull fragments (right ramus of the mandible, left petrous bone, right glenoid region) are also described. Comparisons are made with other South (and East) African fossil hominids. The beautiful preservation simultaneously of most of the deciduous teeth and of the permanent teeth exposed in their crypts allows an accurate analysis of the developmental sequence. A report on the dental developmental status of this juvenile is presented. On the basis of the microanatomical study of the developing permanent teeth, the estimated age at death is 5.2–5.3 years. Reconstructions of the maxillary and mandibular arcades are also offered. The morphological and metrical features of Stw 151 raise the possibility that it may represent a hominid more derived towards an early Homo condition than the rest of the A. africanus sample from Member 4. Am J Phys Anthropol 106:425–465, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

7.
A new fossil hominid partial skeleton (KNM-ER 803) that was discovered from the Plio-Pleistocene sediments to the east of Lake Rudolf is described. It includes parts of a femur, two tibiae, an ulna, two radii, a third metatarsal and several toe bones. There are also two teeth, an upper canine and an upper central incisor. A second new fossil hominid (KNM-ER 164) is represented by a parietal fragment, two vertebrae and some hand bones. A third is represented by a massive left femur (KNM-ER 999). The specimens are described in anatomical detail, some are illustrated and selected measurements are given. It is concluded that they should be attributed to the genus Homo sp. indet. Detailed comparative studies will be published in due course.  相似文献   

8.
Recent fieldwork in the Kibish Formation has expanded our knowledge of the geological, archaeological, and faunal context of the Omo I skeleton, the earliest known anatomically modern human. In the course of this fieldwork, several additional fragments of the skeleton were recovered: a middle manual phalanx, a distal manual phalanx, a right talus, a large and a small fragment of the left os coxae, a portion of the distal diaphysis of the right femur that conjoins with the distal epiphysis recovered in 1967, and a costal fragment. Some researchers have described the original postcranial fragments of Omo I as anatomically modern but have noted that a variety of aspects of the specimen's morphology depart from the usual anatomy of many recent populations. Reanalysis confirms this conclusion. Some of the unusual features in Omo I--a medially facing radial tuberosity, a laterally flaring facet on the talus for the lateral malleolus, and reduced dorsovolar curvature of the base of metacarpal I--are shared with Neandertals, some early modern humans from Skhul and Qafzeh, and some individuals from the European Gravettian, raising the possibility that Eurasian early modern humans inherited these features from an African predecessor rather than Neandertals. The fragment of the os coxae does not unambiguously diagnose Omo I's sex: the greater sciatic notch is intermediate in form, the acetabulum is large (male?), and a preauricular sulcus is present (female?). The preserved portion of the left humerus suggests that Omo I was quite tall, perhaps 178-182 cm, but the first metatarsal suggests a shorter stature of 162-173 cm. The morphology of the auricular surface of the os coxae suggests a young adult age.  相似文献   

9.
自贡四川龙(Szechuanosourus zigongensis sp.nov.)为自贡市大山铺蜀龙动物群中发现的又一肉食龙新材料,本文对它进行了记述。  相似文献   

10.
We describe and analyze a Neandertal postcranial skeleton and dentition, which together show unambiguous signs of right-handedness. Asymmetries between the left and right upper arm in Regourdou 1 were identified nearly 20 years ago, then confirmed by more detailed analyses of the inner bone structure for the clavicle, humerus, radius and ulna. The total pattern of all bones in the shoulder and arm reveals that Regourdou 1 was a right-hander. Confirmatory evidence comes from the mandibular incisors, which display a distinct pattern of right oblique scratches, typical of right-handed manipulations performed at the front of the mouth. Regourdou's right handedness is consistent with the strong pattern of manual lateralization in Neandertals and further confirms a modern pattern of left brain dominance, presumably signally linguistic competence. These observations along with cultural, genetic and morphological evidence indicate language competence in Neandertals and their European precursors.  相似文献   

11.
Summary Border fragments of the octopine Ti-plasmid were tested for their ability to restore tumorigenicity of an avirulent mutant carrying a deleted right border. It was found that neither introduction of left border fragments nor that of small right border fragments at the position of the deletion resulted in a complete restoration of oncogenicity. However, insertion of a larger right border fragment in the deletion mutant gave fully oncogenic strains. In the latter case sequences to the right side of the right border repeat were found to be responsible for a complete restoration of oncogenicity. Also a left border repeat inserted together with this enhancer sequence fully restored the oncogenicity of the deletion mutant. The enhancer-sequence on itself was not able to mediate the transfer of the T-region to the plant cell. Border fragments inserted in inverted orientation in the deletion mutant were able to mediate the transfer of the T-region to the plant cell, but at a reduced frequency.  相似文献   

12.
Myanmarpithecus yarshensis is an amphipithecid primate from the middle Eocene Pondaung Formation in Myanmar. It was previously known based on maxillary fragments with P4–M3 and mandibular fragments with C–P3 and M2–3. This study reports new materials for the genus, including a humeral head fragment, a lingual fragment of the right M2, a lingual fragment of the right M3, and a left I1. These new materials were collected from approximately the same point, and likely belonged to the same individual. The upper molar morphology and size of the new materials show similarity to those of the type specimen, indicating that the new materials can be assigned to M. yarshensis. The humeral head is the first postcranial element that is associated with dental materials for amphipithecids. The morphological similarity between the previously reported larger humerus and this specimen confirms the assignment of the former specimen to Amphipithecidae and suggests common locomotor adaptations in the family. The upper central incisor is large relative to the molar fragments, but is within the variation among extant platyrrhines. The tooth is spatulate-shaped and high crowned, and lacks the mesial process, indicating similarity to I1 of haplorhines and clear differences from that of adapoids. It has been suggested that amphipithecids, including Myanmarpithecus, have affinities with notharctine adapoids, but the morphology of I1 does not support the notharctine hypothesis of the Amphipithecidae.  相似文献   

13.
14.
Abstract:  The holotype of Dollosuchus dixoni (Owen) from the Early–Middle Eocene Bracklesham Beds of England is a set of mandibular fragments that cannot be distinguished from corresponding parts of other longirostrine crocodylians. An isolated humerus from the Bracklesham Beds is consistent with a gavialoid, but it cannot be referred to the holotype of D. dixoni . The name Dollosuchoides densmorei is established for the well-preserved skull and skeleton of a tomistomine from the Middle Eocene of Belgium that had been referred to D. dixoni . It can be clearly distinguished from the basal tomistomine ' Crocodilus ' spenceri Buckland from the Lower Eocene of England, which cannot be referred to Dollosuchoides and is provisionally referred to Kentisuchus Mook. Although basal within Tomistominae, Dollosuchoides is more closely related to Tomistoma than to Kentisuchus .  相似文献   

15.
A partial skeleton from Hadar, Ethiopia (A.L. 438-1) attributed to Australopithecus afarensis is comprised of part of the mandible, a frontal bone fragment, a complete left ulna, two second metacarpals, one third metacarpal, plus parts of the clavicle, humerus, radius, and right ulna. It is one of only a few early hominin specimens to preserve both cranial and postcranial elements. It also includes the first complete ulna from a large A. afarensis individual, and the first associated metacarpal and forelimb remains. This specimen, dated to approximately 3Ma, is among the geologically youngest A. afarensis fossils and is also one of the largest individuals known. Its ulnar to mandibular proportions are similar to those of the geologically older and much smaller A.L. 288-1, suggesting that body size increased without disproportional enlargement of the mandible. Overall, however, analysis of this large specimen and of the diminutive A.L. 288-1 demonstrates that the functional morphology of the A. afarensis upper limb was similar at all body sizes; there is no evidence to support the hypothesis that more than one hominin species is present at Hadar. Morphologically, all apparent apomorphic traits of the elbow, forearm, wrist, and hand of A.L. 438-1 are shared uniquely with humans. Compared to humans, A.L. 438-1 does have a more curved ulna, although A.L. 288-1 does not, and it appears to have had slightly less well-developed manipulatory capabilities of its hands, although still more derived than in apes. We conclude that selection for effective arboreality in the upper limb of Australopithecus afarensis was weaker than in non-hominins, and that manipulative ability was of greater selective advantage than in extant great apes.  相似文献   

16.
This work focuses on paleopathological analysis of one of the skeletons from the Gravettian triple burial of Dolní Vestonice (Moravia) and addresses issues of Upper Paleolithic funerary behavior. The burial includes the well-preserved skeletons of three young individuals. The skeleton in the middle (DV 15) is pathological and very problematic to sex; the other two (DV 13 and DV 14) are males and lie in an unusual position. The young age, the possibility of a simultaneous interment, and the position of the three specimens have given rise to speculations about the symbolic significance of this spectacular and intriguing funerary pattern. The pathological condition of the skeleton in the middle further emphasizes its peculiarity. Main pathological changes of the DV 15 skeleton include: asymmetric shortening of the right femur and of left forearm bones, bowing of the right femur, right humerus, and left radius, elongation of fibulae, dysplasias of the vertebral column, and very marked enamel hypoplasias. Scrutiny of the medical literature suggests that the most likely etiology is chondrodysplasia calcificans punctata (CCP) complicated by trauma and early fractures of the upper limbs. CCP is a rare inherited disorder characterized by stippled ossification of the epiphyses. The cartilaginous stippling is a transient phenomenon that disappears during infancy, leaving permanent deformities on affected bones. Among the different forms of CCP, the X-linked dominant form is that resulting in asymmetric shortening and is lethal during early infancy in males. Thus, survival of DV 15 until young adult age would require the specimen to be a female. Clinical findings often associated with the disease (erythemas, ichthyosis, alopecia, cataracts, and joint contractures, among others) would emphasize the singular aspect of this individual, pointing to a condition that should be carefully taken into account when speculating on the significance of that peculiar burial.  相似文献   

17.
A fossil human femur of Homo heidelbergensis from the site of the Sima de los Huesos (Atapuerca, Spain) was reconstructed from two main proximal and distal portions and numerous smaller fragments from the diaphysis. The use of an evaporative process to separate the bone fragments during their restoration represents an innovative approach in restoring paleontological materials and the intervention has resulted in the reconstruction of a complete femur. To avoid excessive manipulation of the reconstructed femur, a mold (negative) and cast (positive) were made of the restored specimen. This case study provides general protocols which can be widely applied to the restoration of paleontological materials from the moment of their excavation until they are deposited in a research center.  相似文献   

18.
台湾海峡晚更新世人类肱骨化石   总被引:2,自引:0,他引:2  
蔡保全 《人类学学报》2001,20(3):178-185
产自台湾海峡海底的人类右肱骨石化程度高; 个体大而粗壮 ,三角肌粗隆发育 ,骨干上下两半段不在同一纵轴上 ,形成 6 5°的夹角 ,这些显示不同于新石器时代和现代人的原始性状 ,其演化水平和日本的港川人及欧洲的克罗马农人相当。与人化石一同捞出的哺乳动物化石有古菱齿象、野马、最后鬣狗、达氏四不像鹿等 ,表明其时代为晚更新世晚期。  相似文献   

19.
Determination of crown-rump length from fetal long bones: humerus and femur   总被引:1,自引:0,他引:1  
Lengths of the ossified diaphysis of the humerus and femur were measured in 50 fetuses ranging from 65 to 290 mm Crown-Rump length. A significant correlation was found between the diaphyseal length and the CR length. No appreciable difference was noted in diaphyseal lengths of the humerus and femur in fetuses of 85 mm CR length or below. Various growth phases were observed. The difference in length of the femur and humerus is due to a comparative slow growth of the humerus during the later period of prenatal life. Diaphyseal growth rates of the humerus and femur are 0.18 mm and 0.21 mm respectively for every 1 mm increase in CR length. Regression coefficients for the lengths of the ossified shaft of the humerus and femur are 5.35 and 5.00 respectively. With the help of these coefficients, CR length of the fetus was estimated within a range of ± 15 mm. From the estimated CR length, age of the fetus was determined with the help of a standard age and size curve with reasonable accuracy.  相似文献   

20.
The aim of this study was to develop a method for scoring osteochondrosis (OC) by using information from computed tomography (CT), as well as to estimate the heritability for OC scored by means of CT (OCwCT) of the medial and lateral condyles at the distal end of the humerus or the femur of the right and left leg and the sum of these scores (OCT). In addition, we were aiming at revealing the genetic relationship between OCwCT traits and growth in different periods (days from birth to 30 kg (D30), days from 30 to 50 kg (D30_50), days from 50 to 70 kg (D50_70), days from 70 to 90 kg (D70_90), days from 90 to 100 kg (D90_100) and days from birth to 100 kg (D100)). The OCwCT was assessed for 1449 boars, and growth data were collected for these 1449 boars and additional 3779 boars tested in the same time period. All boars were tested as part of the Norsvin Landrace boar test and in the same test station. Heritabilities for OCwCT on anatomical locations varied from 0.21 (s.e. = 0.08) on the medial condyle of the right humerus to 0.06 (s.e. = 0.06) on the lateral condyle of the left femur, whereas OCT exhibited the highest heritability (h2 = 0.31, s.e. = 0.09). Genetic correlations between OCT and OCwCT for the anatomical locations ranged from 0.94 (s.e. = 0.07) for OCT and OCwCT score for the medial condyle of the humerus right side to 0.26 (s.e. = 0.39) for OCT and the lateral condyle of the femur left side. Genetic correlations between D30 and OCT were medium high and unfavourable (rg = −0.74). As the boar gain weight, the relationship between growth rate – expressed as number of days spent growing from one interval to the next – and OCT decreased to 0.12 (s.e. = 0.19, i.e. not significantly different from zero) for the trait D90_100 kg. These changes of genetic correlation coefficients coincide with the maturing of the joint cartilage and skeletal structures. In this study, we demonstrate that CT could be used for selection against OC in breeding programmes in pigs and that the genetic correlations between growth periods and OC are decreasing over time.  相似文献   

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