Les industries lithiques préoldowayennes du début du Pléistocène inférieur du site de Dmanissi en Géorgie

The lithic industry discovered at the Dmanissi site, in Georgia is dated to between 1.81 and 1.7 Myrs and is in association with a rich faunal assemblage composed of large Quaternary vertebrates, as well as several hominid fossils attributed to Homo georgicus, and attests to the human presence on the border of Europe at the beginning of the Lower Pleistocene. The material taken into account in this study was excavated from 1991 to 1999 and comprises 4446 lithic pieces coming from Beds I through VI of the site. The assemblage is very homogenous from the base to the top of the deposits and shows no significative evolutionary tendencies. The lithic material includes a high proportion of whole pebbles (33.8% of the assemblage) coming from two nearby rivers, the Mashavera and the Pinezaouri. They are essentially of fine and coarse grained volcanic tuff, basalt, but also of rhyolite, granite, quartz, as well as other volcanic and metamorphic rocks. Pebbles used for percussion, shaping or debitage were chosen according to their petrographic nature, their morphology and their size. Whole pebbles with percussion marks situated on their extremities or with isolated removals showing convexe edges, are abundant (1.3% of the assemblage). Other pebbles showing percussion marks on a flat face, were used as anvils. Broken pebbles and pebble fragments are very numerous (30.4% of the assemblage). These often show percussion marks on their cortical surfaces. Fractures are generally related to violent percussion as the pebbles were used for striking instruments, or as they were intentionally broken. Some fractures may have been caused accidentally during flaking. Pebble tools represent 4.8% of the lithic assemblage and 10% of the industry, excluding whole and fractured pebbles. These include essentially the primary choppers (pebbles with isolated concave removal negatives) (6% of the industry and 60.1% of the pebble tools), choppers showing continuous cutting edges without a point (2.1% of the industry and 21.2% of the pebble tools). Chopping-tools are very rare (0.8% of the industry and 8.7% of the pebble tools). Although choppers without pointed cutting edges were made using very few removals (3.3 on average), they usually present a regular cutting edge and seem relatively standardised. Cores are well represented (5% of the industry, excluding whole and broken pebbles). They are characterized by a low degree of exploitation and by a frequence of cortical striking platforms. Cored knapped on a single face are most frequent, representing nearly half of the pieces (42.3%), while bifacial cores are present in smaller proportions (34.2%) and multifacial cores are rare (6.3%). Non-modified flakes are very numerous and usually of small size and intentional retouch is absent. On the other hand, the cuttingedges of many the pieces; broken pebbles, pebble tools, cores and flakes, show irregular micro-retouch and irregular retouch such as isolated notches or with continuous or overlapping configuration, sometimes associated with localised crush marks which appear to have been caused by intensive use and heavy working of the pieces. A total of 31.3% of the non-modified flakes show irregular retouch on their cutting edges. One of the main characteristics of the Dmanissi industry appears therefore to be the obtaining of flakes, most often of small size, to be used without modification. The technological and typological characteristics of the lithic industry from Dmanissi allow to attribute the assemblage to a "Pre-Oldowayen" cultural horizon (Lumley de et al., 2004), characterized by the absence of small retouched tools, which appears in East Africa from 2.55 Myrs ago. This cultural horizon is present at the border of Europe, at Dmanissi, around 1.81 Myrs ago and in Western Europe, on the shores of the Mediterranean, at Barranco León about 1.3 Myrs ago and at Fuente Nueva 3 about 1.2 Myrs ago. The lithic industry from the Dmanissi site seems anterior to the Oldowan cultural horizon, characterized by the presence of standardized small retouched tools, which appears in East Africa around 1.8 Myrs ago and emerges in Mediterranean Europe around 800?000 years ago.     

Ostracodes et stratigraphie du néogène et du quaternaire méditerranéens

A stratigraphical chart of marine ostracoda from Lower Miocene to Recent is established. Selected species (approximatively 220) are those morphologicaly well characterized and known from different parts of the Mediterranean area. It appears that: • lower Miocene ostracodes are still poorly known; • specific diversity is high during the Tortonian and the Lower Messinian before the complete disappearance of marine Mediterranean species during the Upper Messinian évaporitic episodes; • during the early Pliocene, about half of the Upper Miocene marine species are reintroduced with the Atlantic waters; other species migrate for the first time in the Mediterranean Sea by the same way; • at the end of the Pliocene or at the beginning of the Pleistocene several species known in Mediterranean since the Middle Miocene or before, such as Cytherella sp. gr. transversa and Ruggieria tetraptera, as well some “nordic guests” such as Hemicythere villosa and Cythere lutea, appear. This work is an opportunity to confirme a Late Miocene age for the Neogene of Skyros (Aegean Sea), to assign the “Upper Pliocene” of Terquem to the Lower Pleistocene and to refute the existence of a pliocene psychrosphere.     

Diverses proprietes de l'absorption du citrate du malate et du succinate par les lutoides du latex d'Hevea brasiliensis

Lutoïds from Hevea latex are microvacuoles with lysosomal character. In vitro in a medium free of energetic substrate citrate, malate and succinate are absorbed. The properties of this absorption and the action of some modifiers are discussed.     

Utilisation des isotopes stables pour l’identification de l’origine du carbone dans la datation du charbon de bois du Paléolithique

Recent years have brought many results of radiocarbon dating the earliest periods of the Upper Palaeolithic that can bring light on the origins of figurative art by Sapiens or Neanderthals. These dates are often close to the limit of the field of radiocarbon dating; because they require measurements of the lowest amounts of radiocarbon, controls are particularly essential. Here we examine the case of the dating of charcoal, whose identification after decontamination is difficult. We suggest a method that does not require additional manipulation to determine whether carbon comes exclusively from charcoal: using the proportion of stable carbon isotopes 13C/12C which is often regarded as a signature (δ13C).     

Baume Flandin et Abri du Maras : deux exemples de débitage laminaire du début du Pléistocène supérieur dans la Vallée du Rhône (sud-est, France)

Assemblages with blades are rare in the south of Europe and most of them are dated from the isotopic stages 4 and 3. The blades are, otherwise, often produced on Levallois cores with unipolar and bipolar methods. According to the sites, the blades are more or less retouched as different kinds of tools. However, there are no specific links between this blank and the tools, and never between the artefacts and the fauna remains (activities). The hypothesis of traditions or needs among time and space are asked without answer, while the blades are present in the north of Europe and the Near East in far older periods. Several sites can be considered to describe the variability of the technical behaviour and the archaeological context of the blades in south-east France, extending to north Italy. The two sites, Abri du Maras and Baume Flandin, located in the middle Rhône valley, yield evidence of a laminar debitage linked to a Levallois method and a “direct” method. The technical choices used in the two sites are accorded to the specificity of the laminar assemblages in the southern Europe.     

Ostracodes du Dévonien moyen et supérieur du Tafilalt (Maroc)

Forty-four ostracod species are recognised from the upper part of the Eifelian to the base of the Famennian of the Djebel Mech Irdane, Bou Tchrafine and El Atrous sections, in the Tafilalt. The majority are in open nomenclature, and one is new: Tubulibairdia tafilaltensis nov. sp. Ostracods belong principally to the Eifelian Mega-Assemblage and they are generally indicative of poorly oxygenated relatively deep marine environments below storm wave base. However, in the base of the Famennian of the Bou Tchrafine section, ostracods belong to the Myodocopid Mega-Assemblage indicative of strong hypoxic water conditions. They confirm that the hypoxic water conditions linked to the “Upper Kellwasser Horizon”, subsisted in North Africa, in the extreme base of the Famennian. Twenty-four ostracod species are recognized in the Djebel Mech Irdane Eifelian/Givetian stratotype, where the most important change in the ostracod fauna is related to the 40 cm-thick level of grey silty-marl located 10 cm below the boundary. However, this change is not indicative of an extinction event at this level. Three zones established on ostracods are recognized in the Frasnian and in the base of the Famennian of the Tafilalt.     

Les ammonites du Bathonien-Callovien du Boulonnais : biodiversité, biostratigraphie et biogéographie

The ammonite fauna of the outcropping Bathonian-Callovian of the Boulonnais (Northern France) is described in detail for the first time. In the middle and Late Bathonian, the fauna is very restricted, reduced to some Perisphinctidae (Procerites) and Clydoniceratidae (Clydoniceras, Delecticeras). The abundance and the biodiversity of assemblages increase during the Callovian. These faunas are typically Subboreal, marked by Gowericeratinae (Kepplerites, Sigaloceras), Kosmoceratinae (Kosmoceras) and Proplanulitinae (Proplanulites), associated with Boreal taxa such as Cadoceratinae (Cadoceras) and Cardioceratidae (Quenstedtoceras), and Submediterranean taxa, Pseudoperisphinctinae (Homoeoplanulites, Poculisphinctes), Peltoceratinae (Pseudopeltoceras) and Macrocephalitinae (Macrocephalites). Representing the only Jurassic onshore outcrops, between the English and Normandy coasts, and the Ardennes area, the interest of these faunas for correlations between the Western and Eastern European (Russian) platforms is emphasized. Palaeobiogeographically, particularly concerning the southward migration/dispersion of the Boreal taxa, the role played by the transgressions/regressions and the resulting paleobathymetric and palaeoclimatic implications is discussed.     

Codes mythiques du Mézinien

Colonized by mammoths, the Eurasian steppe witnessed the birth of religious performances that are based on the reciprocation of life with the human populations moving apace. Plastic art codes attest to this balanced equilibrium with an up-to-present untamed environment, which is still in evidence among some Siberian peoples and the Saami (Lapps) in Europe. Such persistence can be seen as direct legacies and displays an environment that allows a range of attitudes towards animals incompatible with the notion of animal “domestication” as we commonly associate to the European Neolithic.