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The new analysis of the Middle Paleolithic industry from the cave Vindija (Croatia), showed a necessity of revision of the previous obtained data especially considering the use and origin of the raw materials (Kurtanjek and Marci, 1990). The results presented in this study pointed out some new aspects of interpretation. First, the significance of quartz in the Middle Paleolithic was underestimated. At the same time it is obvious that the major change in the use of the raw material was at the beginning of the Upper Paleolithic and of the Epigravettian, especially in the use of chert. The second change is registered in the use of chert between Middle and Upper Paleolithic: the chalky nodules of chert are more frequent in the Upper Paleolithic then the river pebbles used in the production of Middle Paleolithic artefacts. Still, the origin of this new raw material is at the moment unknown.  相似文献   

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The large mammals from travertine deposits in the Denizli basin include the following species: Archidiskodon meridionalis meridionalis, Equus cf. altidens s. l., E. cf. apolloniensis, Stephanorhinus cf. etruscus, Metacervoceros rhenanus, Cervalces (Libralces) ex gr. minor-gallicus, Palaeotragus sp., Bovinae gen. and sp. indet. This association resembles those from the late Villafranchian of Southern and Eastern Europe, and, to some extent, fromWestern Asia, and could be older than 1.2 Ma.  相似文献   

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During the first three hours of beet seed germination, sucrose α-galactosides briefly appear while sucrose and UDPGal contents decrease. The 14C-sucrose penetration into 12-hour-old embryos is followed by a partial eclipse of this compound and its replacement by sucrose α-galactosides. These two processes are more important in sugar than in forage beet. The significance of these results in sugar metabolism is discussed.  相似文献   

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Résumé Des élevages expérimentaux deCallosobruchus maculatus (F.) (Coleoptera, Bruchidae) sur les graines deVicia faba décortiquées ou non, ou sur des pastilles faites des mêmes graines, ont permis de mettre en évidence une barrière empêchant le développement de la bruche.Avec les graines entières, toutes les larves meurent au premier stade enfoncées dans le tégument; alors qu'elles se développent normalement dans les graines décortiquées.Avec des pastilles de broyats de graines non décortiquées, la majorité des larves meurt avant le terme de leur développement; la plus forte mortalité est observée au quatrième stade larvaire. Les larves, qui survivent, accusent une augmentation de leur durée de développement par rapport à celles qui se nourrissent aux dépens des pastilles faites de graines sans tégument.  相似文献   

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Variability is one of the most debated topics in lithic technology studies. For the Middle Pleistocene period, this debate has specifically focused on the significance of large cutting tools such as handaxes and cleavers. This paper presents the stone tool assemblage from Covacha de los Zarpazos site, included in the Galería complex at Sierra de Atapuerca (Burgos, Spain). We analyse the management of lithic raw materials, the reduction sequences identified, and the morphological variation in the shape of large cutting tools. The results show that raw materials play an important role in the final variability of tool shape, although they do not represent any real constraint. However, what determines the main variability of a whole lithic assemblage is the occupation strategy and the specific activities carried out in a given site.  相似文献   

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Many exposures assigned to the Miocene formation of “Marnes de Saubrigues” (southwestern Aquitaine Basin) have been studied. Their revised stratigraphical allocation has made it possible to recognize mainly Middle to Late Burdigalian age deposits which have been widely sampled. They have been correlated with planktonic zones N6 pars-N7 and NN3-NN4 and locally dated 17.7 Ma with Sr isotopes. It is noteworthy that this chronological interval is only known in the southern Basin. An inventory of the rather abundant microplankton is provided, including series crossed by drillings in the Gulf of Biscay. These deposits yield a large diversity of benthic foraminifera, nearly 400 taxa, which can be considered as a reference fauna for western Europe Burdigalian. From a geographic point of view, it has been possible to subdivise the exposures into groups according to their bathymetry. Let us point out the first discovery of Borelis in the Burdigalian of France and in the northeastern Atlantic Miocene as well. Very rare specimens of Cycloclypeus are also present in the Aquitaine Basin. Among smaller foraminifera, the occurrence of Rosalina aguayoi, Pavonitina styriaca, the last appearance of Falsocibicides aquitanicus and the persistance of the genus Almaena must be emphasized. Several assemblages supply diatoms, rare radiolaria and sometimes abundant sponge spicules; the presence of these organisms, seldom reported from the Aquitaine Tertiary, might be linked to upwelling-type currents. Bachmayerella (inc. sed.) is uncommon and cited for the first time in the Burdigalian. A few taxonomical remarks and short notes are given for some species of foraminifera, and palaeoecological details as well. Numerous taxa are represented and comparisons with the foraminifera faunas mainly from the Lower-Middle Miocene of Western Mediterranean and Paratethys are sketched.  相似文献   

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This paper presents for the first time the inventory of the Paleocene and Lower Eocene foraminifers located in the North Pyrenean trough, between the Atlantic Ocean and the neighbourhood of the town Pau. They have been studied from three outcrops. The Bidart Beach section shows the Lasseube Formation from the Cretaceous/Paleogene boundary to the base of the P 3a zone. The Loubieng Quarry section, near Orthez, represents the upper P 3a zone and the lower P 3b zone as well as the Lasseube Formation / Pont Labau Formation boundary. The interval between the upper part of the P 3b zone and the upperest part of the P 5 zone crops out along the Gan - Rébénacq road with a hiatus located at the Paleocene / Eocene boundary, the whole interval belonging to the Pont Labau Formation. 394 taxons of foraminifers are present in this formations: 349 benthic and 45 planktonic species. The Velasco type benthic foraminifers show a middle bathyal depositional environment, with a paleobathymetry included between 500-600 m and 1000 m: Nuttallides truempyi, Osangularia velascoensis, Bulimina trinitatensis. The Midway type species which were transported by the turbidite currents from the lower to middle neritic environments are frequent as well as the Cretaceous reworked species. The species number is low: 29 in the iridium layer of the Cretaceous/Paleogene boundary (P 0 zone). Fauna grows rich quickly in the Pα zone reaching 129 species. The diversity grows up progressively from P α to the P 4a zone (NP 8). The disappearances are rare until his horizon, but their number is bigger than the number of appearances from the P 4b zone. It reaches their maximum between the P 4c zone and the P 5 zone. It shows that the decline of the Paleocene fauna begins around 2 million years before the thermal event of the Paleocene / Eocene boundary in the Aquitaine sections. The disappearances stay important in the Lower Eocene - Ypresian, but the appearance of lots of Eocene species show that the fauna renewal is located in this stage. The Cretaceous taxa dominate in the Paleocene benthonic fauna. The appearance or the disappearance of some species has a stratigraphic value in the Aquitaine region: the disappearance of Coryphostoma incrassata in the P 1b zone, the appearances of Plectina dalmatina, Elongobula grata (P α); Bulimina tuxpamensis (P 2); Tritaxilina cubensis, Thalmannita madrugaensis (P 3a); Svenia bulbosa (P 3b); Discorbis perovalis (P 4a/NP 7); Elongobula pulchra, E. pupa, Asterigerina bartoniana, Neorotalia gr. tuberculata (P 4a/NP 8); Bigenerina pannonica, Pentellina pseudosaxorum (P 5/NP 9-10).  相似文献   

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Vallonnet cave (Alpes-Maritimes, France) provided archaic lithic tools together with a big amount of large mammals of the end of lower pleistocene. At the crossing of diverse ecological niches in time and space, three main levels and within them several smaller units were distinguished. The poorly mineralized bones witnessed a huge diagenetic fragmentation. The presence of the animals in the cave seems to be linked to the reasons of their death. The exhaustive and systematic observation of the bones, like the bears probably used to die inside the cave. Some other carnivores especially hyenas, used the cave as a nursery. Man also occupied the cave and had an activity mainly on large cervid bones and on some other species as well. The very progressive deposit gave a way for carnivores and porcupine to gnaw the bones on the ground before their burial. The succession of actions (man, carnivores and porcupine) on the same bones is characteristic on Vallonnet large mammals bones.  相似文献   

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A detailed investigation of the Bajocian-Bathonian protoglobigerinids and other globigerina-like foraminifera of the Southern Jura Mountains reveals an unsuspected diversity, with seven species of Conoglobigerinidae and two species of Oberhauserellidae. The discovery of two umbilical apertures in Oberhauserella as well as in some Conoglobigerina questions the generic taxonomy and raises the problem of comparisons with literature. For these reasons, five new species have been proposed: Oberhauserellaparocula and O. aff. parocula (with two apertures), “Conoglobigerina”trilocula and “C”.biapertura (with two apertures), C.solaperta and C.pupa. We demonstrate that Globuligerinabalakhmatovae (Morozova, 1961) (here emended) has a small globuligerine aperture as well as G. aff. dagestanica (Morozova, 1961). Despite the different taxonomic concepts, the Southern Jura Mountains associations, that are typical of the epicontinental platform, most closely match those of the Dagestan in the Caucasus. They clearly differ from those of the oceanic Tethys.  相似文献   

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With the emergence of Modern Humans in Africa a new post-Acheulean culture seems to take form: the Middle Stone Age. Although the geo-chronological limits of this period remain unclear, it may however be characterised by behavioural modifications, in particular an important change in the relationship between humans and their environment. Theses changes may partially result from the diversification of stone-tool production techniques, as well as socio-economical conditions. Sites dating of this period show that flake types are more abundant and result from exploitation methods that become gradually more sophisticated from about 300ka.In this context, study of the lithic assemblage from Porc-Epic Cave in Ethiopia contributes to the knowledge about operative methods used during the Middle Stone Age. The combined production of flakes, blades, bladelets and points using various methods, a differential economy towards raw materials and the diversity of tool types produced, underline the large extent of technological variability that the Porc-Epic tool-makers were capable of. We may conclude that, in spite of certain differences concerning raw material acquisition, a chronological homogeneity exists in the production modes and their variability. This apparent homogeneity throughout the stratigraphical sequence underlines the difficulty of attributing a cultural characteristic to stone assemblages of this period.  相似文献   

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Paleogene sedimentation in the Alpes Maritimes and Alpes de Haute Provence regions is composed of one complete sedimentary sequence. This sequence begins with the continental Formation from Microcodium and continues with the Cerithium layers, the Calcaires Nummulitiques and the Marnes Bleues, which are overlaid by the turbidites of the Grès d’Annot Formation. Sedimentation starts in the Nummulites perforatus zone close to the base of ‘the Truncorotaloides rohri zone (P 14) and ends in the Cassigerinella chipolensis-Pseudohastigerina micra zone (P 18) and the NP21 zone in the upper part of the Grès d’Annot. More biomarkers were used in order to define a more detailed local biozonation (biozones AMP 1 to AMP 7). Four local zones were also defined by the last occurrence of Nummulites millecaput and N. perforatus-N. ptukhiani and then by the first appearance of N. retiatus (AMGF 1-4). The evolution of benthic foraminiferal assemblages shows an increase in bathymetry from the internal platform in the Cerithium layers to the calcareous platform with large foraminifers, then to the external platform and the deep offshore environment of the Marnes Bleues and Grès d’Annot. Low faunal diversity in the Grès d’Annot together with the predominance of agglutinated species indicates a poorly oxygenated, organic rich and turbidite environment. Seven steps (SD 1 to SD 7) in the Eocene marine transgression are shown from East to West by detailed local biozonation and sequence analysis. Grès d’Annot sedimentation is also diachronous, beginning within the Truncorotaloides rohri zone (P 14, AMP 1) in the East and ending within the Pararotalia opima opima zone (P 20, middle Rupelian) in the West (Barrême). Small foraminifer Paleogene fauna from the Alpes Maritimes and Alpes de Haute Provence was studied from 400 samples. It is composed of 378 species. Two new taxa are proposed: Fissurina niceana n. sp. and Globocassidulina alpina n. sp. The species from the Escarène and Gorbio neighborhood described by M. von Hantken (1884) were re-examined.  相似文献   

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Das Fangverhalten der Larven von Agrion splendens wird hauptsächlich durch Schwingungen ausgelöst, die durch den Platzwechsel der Beute entstehen. Ein künstlicher mechanischer Stimulator ermöglichte es, nacheinander den Einfluß der Amplitude, der Dauer und der Frequenz der Reize und der Form der Schwingungen zu untersuchen. Die Latenzzeit des Fangschlages verkürzt sich mit zunehmender Frequenz und Amplitude und mit abnehmender Dauer der Reize. Gleichzeitig erhöht sich die Frequenz der Fangschläge, ohne daß der Köder vorher genau untersucht wird. Ein Köder, der mit einer abklingenden oscillatorischen Bewegung vibriert, ist wirksamer als einer mit halb sinusoidaler Bewegung. Künstliche Reizung mit der Ködermethode erlaubte, die sofortige oder verzögerte Wirkung der durch die Beute erzeugten Schwingungen auf das Auslösen des Fangschlages zu prüfen: Die Fangmaske wird während oder nach den Reizserien ausgeworfen. Beide Wirkungen scheinen abhängig von den unregelmäßig verlaufenden oder sinusoidalen Schwingungen, die der Köder erzeugt, und von den Veränderungen der Amplitude während der Reizung: Das Einstellen auf den Fang scheint durch eine wellenförmige Bewegung mit geringfügigen Amplitudenschwankungen erleichtert zu werden. Wenn eine Welle am Anfang oder während der Reizung besonders groß ist, dann führt dies zu einem sofortigen oder späteren Fangschlag.  相似文献   

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