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101.
The Homo erectus cranium found at Gongwangling, near Lantian, China, and dated to ≈1.2 ma BP has been analyzed with respect to its evolutionary position. However, the remains, and especially the internal and external surfaces of the neurocranium, present a series of marked abnormalities. These irregularities consist principally of a pronounced cresting and scalloping of the external surface of the frontal bone and anterior parietal bone and a similar alteration of the internal surface of a mid transverse section of parietal bone that connects with the fossilization break across the anterior parietal bone. There is no obvious exposure of diploë on the surfaces. Woo (Vertebrata PalAsiatica 10:1–16, 1966) briefly ascribed these abnormalities to postmortem erosion, and Caspari (Am. J. Phys. Anthropol. 102:565–568, 1997) has attributed the irregularities of the right supraorbital torus to antemortem trauma. It has been suggested that the pervasive neurocranial alterations might be pathological. Computerized tomography (CT) analysis of the frontal and parietal bones revealed complete radiopacity of the anterior half of the fossil; it is possible to distinguish large frontal sinuses but other details, including in the area of the purported traumatic lesion, are invisible. However, in the posterior frontal bone and preserved portions of the parietal bone the diploë and tables are discernible. Externally on the frontoparietal section and internally on the transverse parietal piece, there are clear erosional lacunae in the associated table, combined with a thin layer of matrix which obscures the eroded diploë externally. The superficial irregularities are therefore due to postmortem taphonomic alterations of the bone and not pathological processes. In addition, it is apparent that the two pieces were embedded in the matrix at different angles, resulting in their differential erosion.  相似文献   
102.
The Pêcheurs cave is a unique example of a Middle Palaeolithic site with three kinds of accumulations: (1) ibex that died in a natural trap, (2) carnivores that died within the cavity, and, (3) a series of short-term occupations by humans who left a few artifacts and a hearth area. Biological patterns of ibex remains (skeletal parts, age) show a homogeneous structure, related to natural death inside the cave. The Chassezac valley is narrow and sinuous, bordered by steep cliffs occupied by well-adapted hoofed-species (Caprinae). Moreover, Les Pêcheurs is a shallow cave, pit-like, and in its deepest part (Sector 4) provided both man and animals with shelter. The presence of a fire place (in the middle of the sequence of Sector 4) firmly indicates the presence of an in situ occupation by a small group of hominids. According to the stratigraphical patterns and the analysis of the lithic assemblages, artifacts do not seem to have been introduced into sediments. The lithic assemblages (technically homogeneous) indicate that small mobile human groups inhabited a cave that offered, by virtue of its morphology, a natural shelter against the cold winds blowing in the Chassezac valley and the plateaus of the south-eastern borders of the Massif Central Mountains. The exploitation of biotopes such as this rocky area constitutes a specific case of human subsistence behavior and settlement strategy. The deepest layer is characterized by a lithic assemblage mostly made of local raw material (quartz) implying a low investment in lithic production. Few flakes made from non-local flints attest to the mobility of the human occupants who moved across these areas and perhaps found in the valleys, short-term refuge.  相似文献   
103.
C.K. Brain documented two interesting patterns in the Pleistocene faunas of Swartkrans Cave, South Africa: (1) The earliest depositional units, Members 1 and 2, preserve high numbers of hominid fossils, while the numbers drop sharply in the more recent Member 3. (2) Burned bone specimens, which seem to have been altered in fires tended by hominids, appear for the first time in Member 3. It was suggested that mastery of fire provided a “shift in the balance of power”, allowing hominids to carry out activities in the cave for the first time unmolested by predators. A lack of butchered bones in Members 1 and 2 and their presence in Member 3 provided support for the hypothesis. However, we have now identified butchered bones in all three units. Further, our findings reveal a lack of variability in butchery patterns through time at Swartkrans; in all cases hominids appear to have been proficient carcass foragers. The real “shift” at Swartkrans does not appear to be one of eventual hominid dominance over carnivores, but rather one of a predominance of leopards at Swartkrans in Member 1 times to the alternating presence of leopards and hyenas in Members 2 and 3. Consistent leopard presence in Member 1 seems to have discouraged hominid activity in the vicinity of the cave. In contrast, by the time Members 2 and 3 were forming hominids may have temporarily used the cave, taking advantage of those periods of carnivore absence.  相似文献   
104.
Retallack, G.J., May 2018. Leaf preservation in Eucalyptus woodland as a model for sclerophyll fossil floras. Alcheringa xxx, xxx–xxx.

A comparison of 29 identifiable vascular plant species in litter beneath Eucalyptus woodland with at least 74 species living nearby showed that the litter is a poor representation of standing vegetation. The leaf litter is dominated by sclerophyll leaves, which are a factor of 6.2 over-represented in litter for Angophora costata, factor of 5.7 for Melaleuca linariifolia, of 3.6 for Eucalyptus spp., of 3.5 for Pteridium esculentum and of 2.1 for Acacia linifolia. Angophora leaves are favored by lignification, with denser venation than Eucalyptus leaves. Sparse emergent oil glands of Angophora also provide fewer entry points for bacteria than rotted internal oil glands of Eucalyptus. The myrtaceous taxa Angophora, Eucalyptus, Melaleuca and Kunzea all have oils dominantly of preservative terpene. Melaleuca linariifolia and Acacia linifolia also have leaves and phyllodes (respectively) that are narrow with a thick lignin midrib. Thickly cuticled, succulent, hirsute, pubescent, and pinnate leaves, and green stems are not favored for preservation, because they rot from the inside out. Conspicuously absent in the leaf litter are nonsclerophyll leaves, most grasses and low herbs. This modern sclerophyll leaf litter matches Sydney Basin Permian and Triassic fossil plant localities above nutrient-poor siliceous paleosols, which may have had much more diversity than the preserved fossil flora. Clayey calcareous paleosol leaf litters and lake deposits may record a truer record of local floristic diversity in deep time than sclerophyll leaf litters.

Gregory J. Retallack [], Department of Earth Sciences, University of Oregon, Eugene, OR 97403-1272, USA.  相似文献   

105.
By means of scanning electron microscopy, four out of a series of twelve inhumations from the Hellenistic Period were examined for traces of the decay process. The changes represented the result of erosion and biological decomposition of human bones on a small island in the northern part of the Persian Gulf over a period of ca. 2200 years. Special emphasis was given to bone preservation and blood cell survival, and to bone changes due to physicochemical erosion and fungus, bacterium, insect and plant-root activity. Related soil and climatic conditions were taken into consideration. The observations should be evaluated to understand the unusual state of preservation of the bones and to avoid possible misinterpretation of pseudo-pathological bone changes as ante-mortem pathology.  相似文献   
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