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71.
Carlos Lorenzo Jos Miguel Carretero Juan Luis Arsuaga Ana Gracia Ignacio Martínez 《American journal of physical anthropology》1998,106(1):19-33
A sexual dimorphism more marked than in living humans has been claimed for European Middle Pleistocene humans, Neandertals and prehistoric modern humans. In this paper, body size and cranial capacity variation are studied in the Sima de los Huesos Middle Pleistocene sample. This is the largest sample of non-modern humans found to date from one single site, and with all skeletal elements represented. Since the techniques available to estimate the degree of sexual dimorphism in small palaeontological samples are all unsatisfactory, we have used the bootstraping method to asses the magnitude of the variation in the Sima de los Huesos sample compared to modern human intrapopulational variation. We analyze size variation without attempting to sex the specimens a priori. Anatomical regions investigated are scapular glenoid fossa; acetabulum; humeral proximal and distal epiphyses; ulnar proximal epiphysis; radial neck; proximal femur; humeral, femoral, ulnar and tibial shaft; lumbosacral joint; patella; calcaneum; and talar trochlea. In the Sima de los Huesos sample only the humeral midshaft perimeter shows an unusual high variation (only when it is expressed by the maximum ratio, not by the coefficient of variation). In spite of that the cranial capacity range at Sima de los Huesos almost spans the rest of the European and African Middle Pleistocene range. The maximum ratio is in the central part of the distribution of modern human samples. Thus, the hypothesis of a greater sexual dimorphism in Middle Pleistocene populations than in modern populations is not supported by either cranial or postcranial evidence from Sima de los Huesos. Am J Phys Anthropol 106:19–33, 1998. © 1998 Wiley-Liss, Inc. 相似文献
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Martinón-Torres M Martín-Francés L Gracia A Olejniczak A Prado-Simón L Gómez-Robles A Lapresa M Carbonell E Arsuaga JL Bermúdez de Castro JM 《Journal of human evolution》2011,61(1):1-11
Here we present a detailed palaeopathological study of the hominin mandible ATE9-1 found at the Sima del Elefante site (TE), Sierra de Atapuerca, Spain. This fossil represents the earliest hominin remains from Western Europe with an age of ca. 1.3 Ma. The specimen displays several dento-gnathic lesions; the antiquity and geographic location of this fossil justifies a detailed palaeopathological study to determine if the pathologies have significantly altered taxonomically relevant features. Our study reveals severe dental attrition combined with generalized hypercementosis, alveolar root exposure, mild periodontal disease, tooth dislocation, and an anomalous occlusal plane. We have also observed calculus deposits, two cystic lesions and an anomalous wear facet compatible with tooth picking. The majority of these pathological signs can be explained by compensatory eruption. We propose that these lesions are associated as causes, consequences, and amplifiers of one another within the framework of heavy and even traumatic occlusion, masticatory habits, or both traumatic occlusion and masticatory habits. Despite the severity of these lesions, occlusion was at least partially functional so it was unlikely to influence the survival of this individual. In addition, the lesions do not prohibit the taxonomic assessment of the mandible. 相似文献
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Juan Luis Arsuaga Jos Miguel Carretero 《American journal of physical anthropology》1994,93(2):241-257
A large sample of hip bones of known sex coming from one modern population is studied morphologically and by multivariate analysis to investigate sexual dimorphism patterns. A principal component analysis of raw data shows that a large amount of the hip bone sexual dimorphism is accounted for by size differences, but that sex-linked shape variation is also very conspicuous and cannot be considered an allometric consequence of differences in body size between the sexes. The PCA of transformed (“shape”) variables indicates that the female hip bones are different in those traits associated with a relatively larger pelvic inlet (longer pubic bones, a greater degree of curvature of the iliopectineal line, and a more posterior position of the auricular surface), as well as a broader sciatic notch. The analysis of nonmetric traits also shows marked sexual dimorphism in the position of the sacroiliac joint in the iliac bone, in the shape of the sciatic notch, in pubic morphology, and in the presence of the pre-auricular sulcus in females. When the australopithecine AL 288-1 and Sts 14 hip bones are included in the multivariate analysis, they appear as “ultra-females.” In particular these early hominids exhibit extraordinarily long pubic bones and iliopectineal lines, which cannot be explained by allometry. © 1994 Wiley-Liss, Inc. 相似文献
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E. Aguirre J. L. Arsuaga J. M. Bermúdez de Castro E. Carbonell M. Ceballos C. Díez J. Enamorado Y. Fernández-Jalvo E. Gil A. Gracia A. Martín-Nájera I. Martínez J. Morales A. I. Ortega A. Rosas A. Sánchez B. Sánchez C. Sesé E. Soto T. J. Torres 《Human Evolution》1990,5(1):55-73
The Atapuerca railway Trench and Ibeas sites near Burgos, Spain, are cave fillings that include a series of deposits ranging
from below the Matuyama/Bruhnes reversal up to the end of Middle Pleistocene. The lowest fossil-bearing bed in the Trench
contains an assemblage of large and small Mammals includingMimomys savini, Pitymys gregaloides, Pliomys episcopalis, Crocuta crocuta, Dama sp. and Megacerini; the uppermost assemblage includesCanis lupus, Lynx spelaea, Panthera (Leo) fossilis, Felis sylvestris, Equus caballus steinbeimensis, E.c. germanicus, Pitymys
subterraneus, Microtus arvalis agrestis, Pliomys lenki, and alsoPanthera toscana, Dicerorbinus hemitoechus, Bison schoetensacki, which are equally present in the lowest level. The biostratigraphic correlation and dates of the sites are briefly discussed,
as are the paleoclimatic interpretation of the Trench sequences. Stone artifacts are found in several layers; the earliest
occurrences correspond to the upper beds containingMimomys savini. A set of preserved human occupation floors has been excavated in the top fossil-bearing beds. The stone-tool assemblages
of the upper levels are of upper-medial Acheulean to Charentian tradition. The rich bone breccia SH, in the Cueva Mayor-Cueva
del Silo, Ibeas de Juarros, is a derived deposit, due to a mud flow that dispersed and carried the skeletons of many carnivores
and humans. The taxa represented are:Ursus deningeri (largely dominant),Panthera (Leo) fossilis, Vulpes vulpes, Homo sapiens var. Several traits of both mandibular and cranial remains are summarized. Preliminary attempts at dating suggest that the
Ibeas fossil man is older than the Last Interglacial, or oxygen-isotope stage 5. 相似文献
78.
Emiliano Bruner Hana Píšová Laura Martín-Francés María Martinón-Torres Juan Luis Arsuaga Eudald Carbonell José María Bermúdez de Castro 《Comptes Rendus Palevol》2017,16(1):71-81
The TD6-2 level of the Gran Dolina cave site (Sierra de Atapuerca, Burgos, Spain) has yielded an assemblage of about 170 human fossil remains dated to > 800 ka (probably MIS 21) and assigned to the species Homo antecessor. In this study, we describe for the first time a large portion of a parietal bone (ATD6-100/168). The morphology of the fractures on the bones is compatible with a peri-mortem trauma. The superior parietal areas are flat. There is a large parietal foramen and one smaller accessory parietal foramen. Middle meningeal vessels are not particularly developed, but they are distributed in both anterior and posterior districts, with the parietal vasculature originating from the posterior branch. The meningeal vessels show multiple minor connections with the pericranial and diploic vascular systems. The diploe is not particularly developed, and large diploic channels are not detected. The bone is thin when compared with adult fossil humans, and equivalent to juvenile values. All these characters suggest that the parietal ATD6-100/168 probably belonged to a juvenile individual, with plesiomorphic endocranial traits similar to those described for H. ergaster/erectus. The derived temporal, maxillary and dental traits in Homo antecessor and the primitive parietal morphology further point to distinct (mosaic) patterns of morphological evolution of face and braincase. 相似文献
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Trypanosomatida parasites, such as trypanosoma and lishmania, are the cause of deadly diseases in many third world countries.
A distinctive feature of these organisms is the three dimensional organization of their mitochondrial DNA into maxi and minicircles.
In some of these organisms minicircles are confined into a small disk volume and are topologically linked, forming a gigantic
linked network. The origins of such a network as well as of its topological properties are mostly unknown. In this paper we
quantify the effects of the confinement on the topology of such a minicircle network. We introduce a simple mathematical model
in which a collection of randomly oriented minicircles are spread over a rectangular grid. We present analytical and computational
results showing that a finite positive critical percolation density exists, that the probability of formation of a highly
linked network increases exponentially fast when minicircles are confined, and that the mean minicircle valence (the number
of minicircles that a particular minicircle is linked to) increases linearly with density. When these results are interpreted
in the context of the mitochondrial DNA of the trypanosome they suggest that confinement plays a key role on the formation
of the linked network. This hypothesis is supported by the agreement of our simulations with experimental results that show
that the valence grows linearly with density. Our model predicts the existence of a percolation density and that the distribution
of minicircle valences is more heterogeneous than initially thought. 相似文献