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1.
禄丰古猿幼年下颌骨的研究 总被引:1,自引:1,他引:0
本文记述了1980年在云南省禄丰县石灰坝村禄丰古猿地点发现的最晚中新世禄丰古猿的幼年下颌骨PA869。作者将此标本与西瓦古猿的,南方古猿的和现生大猿的幼年下颌进行了对比,记述了禄丰古猿幼下年颌的若干特征,这些特征表明禄丰古猿幼年下颌体各部主要尺寸的比例关系本种成年的十分相似。 相似文献
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禄丰大猿化石分类的修订 总被引:11,自引:3,他引:8
本文将禄丰西瓦古猿与巴基斯坦和土耳其的标本进行了对比,认为前者与后者有明显的不同。提出把禄丰的标本修订为禄丰古猿属同名种(Lufengpithecus lufengensis)。 相似文献
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釉面横纹的数目可用于推断个体牙齿的牙冠形成时间,在生长发育研究中具有重要的意义。本研究运用数码体视显微镜和扫描电镜观察了云南石灰坝禄丰禄丰古猿(简称禄丰古猿)30枚齿冠完整的前部牙齿,包括上下颌中门齿6枚、侧门齿10枚和犬齿14枚。根据唇侧面釉面横纹计数的观察结果,分别以7天和9天芮氏线生长周期,估算各齿型的牙冠形成时间,结果显示:以生长周期7天计算,中门齿牙冠形成时间约为3.6-4.1年,侧门齿牙冠形成时间约为2.7-3.7年,犬齿牙冠形成时间约为4.2-7.0;以生长周期9天计算,中门齿牙冠形成时间约为4.4-5.2年,侧门齿牙冠形成时间约为3.4-4.7年,犬齿牙冠形成时间约为5.2-8.8年。为更深入地了解禄丰古猿牙冠形成时间在不同齿型及性别间足否存在明显差异,本文用SPSS软件对其进行显著性差异检验。采用小样本平均值的t值假设检验(置信区间为95%),结果如下:禄丰古猿前部牙齿的牙冠形成时间在各类牙齿的上下颌中不存在显著性差异;犬齿牙冠形成时间存在非常显著的性别差异,雄性牙冠形成时间明显长于雌性,侧门齿也存在显著的性别差异,而中门齿性别间则无显著性差异。此外对禄丰古猿中门齿,侧门齿和犬齿的牙冠形成时间进行单因素方差分析并两两对比,结果显示中门齿与侧门齿的牙冠形成时间不存在显著性差异,而犬齿与中门齿和侧门齿均存在显著性差异,犬齿牙冠形成时间明显长于门齿。同时也对禄丰古猿前部牙齿的牙冠形成时间与齿冠高进行相关性分析,其结果表明两者有显著的正相关性。将禄丰古猿与其他古猿和现生大猿、南方古猿以及人属成员进行对比,结果显示其前部牙齿牙冠形成时间长于原修康尔猿、南方古猿、傍人、人属成员,接近于蝴蝶禄丰古猿和大猩猩,而明显小于黑猩猩、华南化石猩猩及现生猩猩。 相似文献
4.
禄丰古猿牙齿釉质生长线与个体发育问题研究 总被引:2,自引:1,他引:1
运用扫描电子显微镜,对4枚禄丰古猿牙齿(恒齿)釉质结构进行了观察研究,发现:禄丰古猿牙齿釉质表面有明显的釉面横纹结构;釉面横纹的密度向牙颈方向逐渐增大;观察记数了4枚牙齿的釉面横纹数,进而推算出牙冠的形成时间和年龄。与化石人科成员,现代人及现生大猿比较,禄丰古猿牙冠发育模式及时间,与南方古猿纤细种比较接近或相似,明显长于南方古猿粗壮种,有别于现生大猿。 相似文献
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对出自禄丰石灰坝的26个禄丰古猿下颌齿列的246枚恒齿进行了观察研究,发现禄丰古猿具有普遍的带状釉质发育不全(LEH)现象,个体LEH比例为100%,恒齿LEH比例为85%。乳齿几乎没有LEH现象,第一恒臼齿的LEH比例也很低仅57%。根据牙齿萌出顺序及现代大猿的牙齿发育年龄特征,作者推断2—3岁之前的幼儿古猿很少出现釉质发育不全现象,这可能与母体的营养关照有关。禄丰古猿的LEH的发生频率具有明显的季节性,结合中新世晚期气候变化特征、古猿的生态环境、生活习性及食性特征分析,作者推测:季节性营养不良可能是造成禄丰古猿釉质发育不全的主要原因。 相似文献
7.
元谋小河村古猿上颌骨化石的初步研究 总被引:1,自引:0,他引:1
1987年初和1989年11月,分别在云南省元谋县小河村的蝴蝶梁子和盖排梁子,发现了两件古猿上颌骨化石(YM12和YM150),原研究者将前者订名为“腊玛古猿属蝴蝶种(Ramapithecushudienesis)。”作者研究了这两件标本,从形态上看,两者十分相似,从尺寸上可分为大、小两个类型,它们可能是同一种的雌雄个体,:即前者大,为雄性;后者小,为雌性。它们与禄丰古猿(Lufengpithecuslufengensis)的形态非常相似,它们应归为禄丰古猿属。但这两件小河的标本,又有它们的固有特点,所以暂归之于Lufengpithecussp.。 相似文献
8.
Alilepus longisinuosus sp.nov.系禄丰古猿动物群兔形目的唯一代表。基于自1976年以来采集到的69件标本,本文对新种的特征,特别是在种内的变异作了描述;并将其与华北及欧洲其它地点的翼兔作了比较。研究结果表明,可能由Gobiolagus或Ordolagus进化而来的Alilepus,在中新世晚期有较大的分化;禄丰的翼兔似乎代表该属向南亚现生的Nesolagus进化的一种。 相似文献
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The hominid mandible and a third metatarsal found in Dmanisi (Republic of Georgia) are accompanied by a rich faunal assemblage and a core-chopper stone tool industry. The mandible represents a somewhat isolated morphological type of Homo erectus that appears, given the combination of its primitive and advanced traits and specific dental morphology, to be a forerunner of both late H. erectus and early archaic H. sapiens. The faunal assemblage mostly consists of Villafranchian mammals, with the majority of the species assigned to an early phase of the Upper Villafranchian (Late Villanian and Early Biharian). Faunal and paleobotanical evidence as well as the depositional nature of the site indicate that hominid occupation took place in a mosaic environment of open steppe and gallery forests. Both the concentration of resources and the warm climatic conditions in the Dmanisi region at the beginning of the early Pleistocene were favorable for hominid occupation. It is possible that hominids reached the Caucasus through the Levantine corridor, and that the environment of this region allowed them to establish a stronghold and later colonize adjacent areas. 相似文献
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The morphology and affinities of early and middle Pleistocene Homo erectus in East Asia have been explored since the late nineteenth century. A fragmentary hominid cranium (Nanjing no.1) recovered in Tangshan near Nanjing, China bears directly on these issues. In the present study, the morphological features of Nanjing no.1 are described and compared with Homo erectus from both Eurasia and Africa. Our results indicate that this middle Pleistocene hominid fossil should be referred to as Homo erectus. The sharing of typical Homo erectus features with African and European counterparts demonstrates that Homo erectus is a widely distributed lineage that evolved during the million years after its Pliocene origins. The differences between Nanjing no.1 and Zhoukoudian suggest certain level of regional variation in East Asian Homo erectus. 相似文献
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Kaifu Y Baba H Aziz F Indriati E Schrenk F Jacob T 《American journal of physical anthropology》2005,128(4):709-726
Temporal changes, within-group variation, and phylogenetic positions of the Early Pleistocene Javanese hominids remain unclear. Recent debate focused on the age of the oldest Javanese hominids, but the argument so far includes little morphological basis for the fossils. To approach these questions, we analyzed a comprehensive dentognathic sample from Sangiran, which includes most of the existing hominid mandibles and teeth from the Early Pleistocene of Java. The sample was divided into chronologically younger and older groups. We examined morphological differences between these chronological groups, and investigated their affinities with other hominid groups from Africa and Eurasia. The results indicated that 1) there are remarkable morphological differences between the chronologically younger and older groups of Java, 2) the chronologically younger group is morphologically advanced, showing a similar degree of dentognathic reduction to that of Middle Pleistocene Chinese H. erectus, and 3) the chronologically older group exhibits some features that are equally primitive as or more primitive than early H. erectus of Africa. These findings suggest that the evolutionary history of early Javanese H. erectus was more dynamic than previously thought. Coupled with recent discoveries of the earliest form of H. erectus from Dmanisi, Georgia, the primitive aspects of the oldest Javanese hominid remains suggest that hominid groups prior to the grade of ca. 1.8-1.5 Ma African early H. erectus dispersed into eastern Eurasia during the earlier Early Pleistocene, although the age of the Javanese hominids themselves is yet to be resolved. Subsequent periods of the Early Pleistocene witnessed remarkable changes in the Javanese hominid record, which are ascribed either to significant in situ evolution or replacement of populations. 相似文献
14.
Dennell R 《Journal of human evolution》2003,45(6):421-440
This paper examines the evidence for hominids outside East Africa during the Early Pleistocene. Most attention has focused recently on the evidence for or against a late Pliocene dispersal, ca. 1.8 Ma., of hominids out of Africa into Asia and possibly southern Europe. Here, the focus is widened to include North Africa as well as southern Asia and Europe, as well as the evidence in these regions for hominids after their first putative appearance ca. 1.8 Ma. It suggests that overall there is very little evidence for hominids in most of these regions before the Middle Pleistocene. Consequently, it concludes that the colonising capabilities of Homo erectus may have been seriously over-rated, and that even if hominids did occupy parts of North Africa, southern Europe and southern Asia shortly after 2 Ma, there is little evidence of colonisation. Whilst further fieldwork will doubtless slowly fill many gaps in a poorly documented Lower Pleistocene hominid record, it appears premature to conclude that the appearance of hominids in North Africa, Europe and Asia was automatically followed by permanent settlement. Rather, current data are more consistent with the view that Lower Pleistocene hominid populations outside East Africa were often spatially and temporally discontinuous, that hominid expansion was strongly constrained by latitude, and that occupation of temperate latitudes north of latitude 40 degrees was largely confined to interglacial periods. 相似文献
15.
本文讨论了巫山人类门齿的归属问题。根据形态及数据分析,它可能为晚期智人的右上外侧门齿、后期混入了巫山龙骨坡洞穴沉积之中。 相似文献
16.
A fragment of mandible and a maxillary incisor of different individuals from the Longgupo Cave, China have been cited as evidence
of an early dispersal ofHomo from Africa to Asia. More specifically, these specimens are said to resemble “Homo ergaster” orHomo habilis, rather than the species usually thought to be the first Asian colonizer,Homo erectus. If this supposition is correct, it calls into question which hominid (sensu stricto) first left Africa, and why hominids became a colonizing species. Furthermore, the Longgupo remains have been used to buttress
the argument thatHomo erectus evolved uniquely in Asia and was not involved in the origins of modern humans. We question this whole line of argument because
the mandibular fragment cannot be distinguished from penecontemporary fossil apes, especially the Late Miocene-Pliocene Chinese
genusLufengpithecus, while the incisor is indistinguishable from those of recent and living east Asian people and may be intrusive in the deposit.
We believe that the Longgupo mandible represents the relic survival of a Late Miocene ape lineage into a period just prior
to the dispersal of hominids into southeastern Asia, with some female dental features that parallel the hominid condition.
If the Longgupo mandibular fragment represents a member of theLufengpithecus clade, it demonstrates that hominoids other thanGigantopithecus and the direct ancestor of the orangutan persisted in east Asia into the Late Pliocene, while all other Eurasian large-bodied
hominoids disappeared in the Late Miocene. 相似文献
17.
Cranial morphometry of early hominids: facial region 总被引:2,自引:0,他引:2
We report here on early hominid facial diversity, as part of a more extensive morphometric survey of cranial variability in Pliocene and early Pleistocene Hominidae. Univariate and multivariate techniques are used to summarise variation in facial proportions in South and East African hominids, and later Quaternary groups are included as comparators in order to scale the variation displayed. The results indicate that "robust" australopithecines have longer, broader faces than the "gracile" form, but that all australopithecine species show comparable degrees of facial projection. "Robust" crania are characterised by anteriorly situated, deep malar processes that slope forwards and downwards. Smaller hominid specimens, formally or informally assigned to Homo (H. habilis, KNM-ER 1813, etc.), have individual facial dimensions that usually fall within the range of Australopithecus africanus, but which in combination reveal a significantly different morphological pattern; SK 847 shows similarly hominine facial proportions, which differ significantly from those of A. robustus specimens from Swartkrans. KNM-ER 1470 possesses a facial pattern that is basically hominine, but which in some respects mimics that of "robust" australopithecines. Early specimens referred to H. erectus possess facial proportions that contrast markedly with those of other Villafranchian hominids and which suggest differing masticatory forces, possibly reflecting a shift in dietary niche. Overall the results indicate two broad patterns of facial proportions in Hominidae: one is characteristic of Pliocene/basal Pleistocene forms with opposite polarities represented by A. boisei and H. habilis; the other pattern, which typifies hominids from the later Lower Pleistocene onwards, is first found in specimens widely regarded as early representatives of H. erectus, but which differ in which certain respects from the face of later members of that species. 相似文献
18.
G P Rightmire 《American journal of physical anthropology》1980,53(2):225-241
Cranial, dental, and mandibular remains of eight Olduvai hominids are described in detail. Four individuals were recovered in situ in Beds II to IV, while three more are most probably derived from Bed IV, the Masek Beds and the Lower Ndutu Beds. One specimen is of uncertain provenance. Deposits from which the fossils were collected range from late Lower Pleistocene to Middle Pleistocene in age. Of particular interest are three fragmentary lower jaws, which can be compared to mandibles of Homo erectus known from localities in Northwest Africa and China. Olduvai hominid 22, a nearly complete half mandible with crowns of P3-M2 in place, shares many anatomical features with fossils from Ternifine and Choukoutien. This individual is also similar to a jaw from the Kapthurin Formation west of Lake Baringo, Kenya. How best to interpret these comparisons is not clear, but in view of marked similarities between specimens representing geographically diverse populations from different time periods, it may be unwise to rely on mandibular evidence alone to document the presence of regional lineages. Gradual change and continuity within a sequence of Northwest African Homo fossils has been endorsed by many workers, but such hypotheses cannot be tested adequately with the fragmentary jaws available. 相似文献
19.
Antonio Rosas Jos Maria Bermúdez De Castro 《American journal of physical anthropology》1998,107(2):145-162
The recent discovery of unexpectedly ancient human remains has fuelled interest about the first dispersion of Homo outside Africa. The Dmanisi mandible is perhaps one of the most interesting findings, as it supposedly represents one of the oldest hominids outside of Africa. Recently, different interpretations have been published about this specimen. Our comparison of the Dmanisi mandible with a large sample of mandibles and teeth has led us to a new interpretation. In our view, the Dmanisi mandible exhibits a unique combination of traits. Some of its features, taken in isolation, may be attributed to morphological extremes within the genus Homo. The architecture of the mandible as well as the morphology and dimensions of incisors, canines, and P3s are clearly primitive. However, dental traits such as the reduction of the talonid in the P4s and a distally decreasing molar series seems to be derived. Some combinations of these traits are found in specimens of Homo ergaster and differ from those generally present in later hominids. Thus, we propose that the Dmanisi mandible might be taxonomically classified as Homo sp. indet. (aff. ergaster). Furthermore, some aspects of the dentition in Dmanisi display close similarities to Asian Homo erectus. If the 1.8–1.6 Myr dating for the Dmanisi mandible is correct, the differentiation of the Asian branch of the genus Homo could be regarded as a very ancient event. Am J Phys Anthropol 107:145–162, 1998. © 1998 Wiley-Liss, Inc. 相似文献
20.
Tooth fragments are an appreciable but neglected proportion of fossil hominid specimens. The present study on 47 naturally fractured enamel surfaces of premolar and molar teeth of Plio-Pleistocene East African hominids measured enamel thickness, slope of incremental lines (striae of Retzius), and the morphology of Hunter Schreger bands (HSBs). Specimens allocated to three categories--"robust" australopithecines (EAFROB), "early Homo" (EAFHOM), and "unknown"--were photographed in ethanol with polarised light. Enamel thickness was measured on the occlusal (OT), cuspal (CT), and lateral (LT) aspects. The angle of intersection of striae of Retzius (D) with the enamel-dentine junction (EDJ) was recorded, together with the degree of curvature and width of Hunter-Schreger bands (HSB). Absolute measurements of enamel thickness were scaled by using two allometry correction factors. Absolute thicknesses of all enamel measurements were significantly greater in the EAFROB (OT 3.1 mm; CT 3.3 mm; LT 2.4 mm) compared with EAFHOM (OT 1.4 mm; CT 1.6 mm; LT 1.6 mm) categories. Correction for size reduces the mean difference between the two taxa, but CT and OT thickness remain significantly different (P less than 0.05). HSBs in EAFROB were relatively straight and narrower (means = 52.8 micron) than in EAFHOM, which are more curved and wider (means = 62.0 micron), suggesting greater enamel prism decussation in early Homo. The slope of striae was less in EAFROB permanent molars (means = 23 degrees) compared with EAFHOM (means = 31 degrees), indicating faster rates of coverage during crown formation in "robust" australopithecines. We conclude that the study of fractured enamel surfaces can contribute to our understanding of the systematic relationships and patterns of enamel growth of early hominids. 相似文献