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1.
J. Desmond Clark 《Journal of human evolution》1987,16(7-8)
Significant differences in activity-site patterning and artifact composition at Middle Pleistocene localities in Ethiopia's high plains and Afar Rift are indications of both single-episode, small-site residues from small groups and multi-purpose, multiple occupation sites from which larger, temporary groupings might be inferred. Reconstructions of palaeo-environments and geography show that large assemblages relate to relatively stable topography, such as stream channels or lake margins, while small assemblages are more common in deltaic situations of rapid sedimentation and burial in the Rift that preclude possibility of reoccupation. A model for Acheulian socio-economic behaviour within the drier African savanna, based (in part) on chimpanzee behaviour in open savanna habitats, is proposed. This takes the form of organization into relatively extensive territories, each with several more closed-vegetation core areas, of limited extent close to permanent water, surrounded by more extensive areas of drier, open savanna, regularly exploited and patrolled by small groups. Movement from one core area to another was rapid and made together as a group, to minimize danger from large predators and competition from other hominid groups. 相似文献
2.
V. Formicola 《Human Evolution》1986,1(6):557-563
Late Epigravettian postcranial human remains from the Arene Candide cave (Finale Ligure, Savona, Italy) were compared with
the Neolithic sample found in the upper levels of the same site. Data on length, diaphyseal circumference and diameter of
clavicle, humerus, radius, femur and tibia were collected from male specimens having all these bones. The Epigravettian sample
is characterized by significantly greater tibial length, robustness and platycnemia, significantly lower circumferences in
the upper limb bones and the clavicle, and a high degree of asymmetry. Variations observed in lower limb bones are those expected
on the basis of the different functional requirements of a hunting and gathering economy compared to a more sedentary, food
producing economy. Differences in the upper limb bones and the clavicle are less explicable. However, considering that in
spite of a more slender structure, the Epigravettian bones show evidence of vigorous use, variation in upper limb could result
from qualitatively different involvements. 相似文献
3.
4.
C. Brombacher 《Vegetation History and Archaeobotany》1997,6(3):167-186
This paper describes the results of the archaeobotanical examination of four Late Neolithic lakeshore settlements on Lake
Biel in Switzerland. Due to the excellent preservation conditions in lakeshore settlements, non-carbonized as well as carbonized
seeds and fruits were recovered in large numbers. In addition to the diaspore analyses, some samples of charcoal and moss
were identified. The spectrum of cultivated plants was markedly different between the sites. In the transition from the 34th
to 33rd century B.C. (sites Nidau, Lüscherz and Lattrigen ‘VI’) naked wheat and barley were predominant, while in the 32nd
century B.C. (Lattrigen'VII') emmer (a glume wheat) was most abundant. Flax and opium poppy were of great importance during
the whole late Neolithic period. In addition to cereals, a large number of cereal weeds were detected. The wild flora included
a high percentage of aquatic and lake-shore plants which results from the strong influence of water on the cultural layers.
Taxa of flood-plain forest are also common. The proportion of potential grassland plants was low (in total only 13 taxa) which
suggests that in addition to the cultivated fields only few pastures and grassland areas existed close to the settlements. 相似文献
5.
C. A. Burga 《Plant Ecology》1982,49(3):173-186
In the first part, an overview of the history of palynological researeh in Switzerland and particularly in the Grisons is given, with a map showing all investigated areas in the Grisons. The second part deals with the significance of the pollenanalytical research in the Grisons, namely, the history of vegetation during the Late and Post Glacial, climatic fluctuations and applications in geomorphology, archaeology and forestry research. Finally, some results concerning the history of vegetation during the Late and Post Glacial are discussed.I would like to thank my colleague H. Holzhauser for his help with the drawing of the figures. 相似文献
6.
Hydrological conditions prevailing before, during and after the Messinian salinity crisis in Sicily have been approached using dinoflagellate cyst records. The synthetic sequence considered is based on five classical sections from the Caltanissetta Basin. Our interpretations are based on the recognition of autochthonous, allochthonous and reworked population among the dinocyst assemblages. For the first time, sea-surface temperatures and seasonal salinity contrasts were tentatively reconstructed using a “Mutual Climatic Range Method”. Sicilian late Tortonian deposits correspond to marine environment with significant terrestrial inputs favourable to eutrophic dinocyst species. Immediately after the beginning of the Messinian Stage, euryhaline assemblages took place, followed by meso-hyperhaline taxa, within a general trend to shallowing. At the end of the Tripoli diatomitic Formation, environment appears confined, with regular oceanic inflows. Such marine inflows remain persistent during the deposition of the salt Member, witnessing the probable persistence of nearby normal marine sea-surface water conditions in the Mediterranean Sea but with possible reduced hydrological circulation and/or low nutrient component. Such inflows are slightly decreasing up to the top of the Sicilian Upper Evaporites. At the same time, river inputs appear weak during the salt deposition, as the consequence of a rather dry climatic context. As shown by reworking activity, terrestrial inputs increase progressively from the base of the Upper Evaporites. During the Lago Mare period, while climate remains rather dry (absence of freshwater algae inputs, very low amount in trees requiring humid conditions), local deposition environment is confined with mesohaline to hypohaline sea-surface waters, in a context with relatively high seasonal sea-surface salinity contrast (up to 6‰). The very high reworking observed in the Arenazzolo silts, in addition to slightly increasing water depth, led us to consider the presence of a discontinuity between the Lago Mare and the Arenazzolo Fms. We consider the Arenazzolo Formation as a transgressive facies following a deep downcutting period. The Arenazzolo Formation presents a two-step development. The first one, correlative with the presence of a G. etrusca (a species with Paratethyan affinities), corresponds to a relative high-stand sea-level with oceanic influxes, low seasonal sea-surface salinity contrast and probable more humid context, as revealed by the important freshwater algal inputs. During the second step, salinity becomes much more variable, with a clear increase of seasonal sea-surface salinity contrast, a possible slight mean sea-surface temperature increase (only few degrees) and a clear weakening of the river inputs. Taking the proposed Zanclean position of the Arenazzolo Fm. into consideration, we state that mean sea-surface temperature did not change significantly from the base of the Messinian to the earliest Zanclean. At 5.33 Ma, the suddenly achieved flooding restored a fair, deep oceanic environment characterized, at the beginning, by a clear mean sea-surface temperature cooling (up to 6-7 °C) and a nutrient depletion, associated with the basins starvation. Sea-surface salinities were normal, with very low seasonal contrast. Hydrodynamics then nutrient supply became then quite normal from c.a. 5.08 Ma. The status of the Sicilian Caltanissetta Basin as a marginal basin although fastly deepening and the stratigraphical location of the Messinian discontinuity at the base of the Arenazzolo is the scenario that best matches our dinocyst record. 相似文献
7.
河南淅川盆地的恐龙蛋 总被引:4,自引:2,他引:4
记述了河南淅川盆地10个地点发现的恐龙蛋化石计6种,分属于4个科6个属.其中新属1个、新种2个。新属、新种滔河扁圆蛋(Placoolithustaohensis)以其特有的壳单元分枝特征成为树枝蛋科的新型分子;另一新种渐川树枝蛋(Dendroolithusxichuanensis)与湖北安陆王店树枝蛋(D.wandianensis)性质相似,两者时代应彼此相当;含滔河扁圆蛋的马家村组下部应与其下含淅川树枝蛋的高沟组划归同一时段为宜,即晚白垩世早期;含副圆形蛋、椭圆形蛋、长形蛋、南雄蛋的马家村组中、上部和其上的寺沟组,时代应属晚白垩世中、晚期。 相似文献
8.
Excavations at Liang Bua, a limestone cave on the island of Flores, East Indonesia, have yielded a well-dated archaeological and faunal sequence spanning the last 95 k.yr., major climatic fluctuations, and two human species - H. floresiensis from 95 to 17 k.yr.1, and modern humans from 11 k.yr. to the present. The faunal assemblage comprises well-preserved mammal, bird, reptile and mollusc remains, including examples of island gigantism in small mammals and the dwarfing of large taxa. Together with evidence from Early-Middle Pleistocene sites in the Soa Basin, it confirms the long-term isolation, impoverishment, and phylogenetic continuity of the Flores faunal community. The accumulation of Stegodon and Komodo dragon remains at the site in the Pleistocene is attributed to Homo floresiensis, while predatory birds, including an extinct species of owl, were largely responsible for the accumulation of the small vertebrates. The disappearance from the sequence of the two large-bodied, endemic mammals, Stegodon florensis insularis and Homo floresiensis, was associated with a volcanic eruption at 17 ka and precedes the earliest evidence for modern humans, who initiated use of mollusc and shell working, and began to introduce a range of exotic animals to the island. Faunal introductions during the Holocene included the Sulawesi warty pig (Sus celebensis) at about 7 ka, followed by the Eurasian pig (Sus scrofa), Long-tailed macaque, Javanese porcupine, and Masked palm civet at about 4 ka, and cattle, deer, and horse - possibly by the Portuguese within historic times. The Holocene sequence at the site also documents local faunal extinctions - a result of accelerating human population growth, habitat loss, and over-exploitation. 相似文献
9.
10.