Search results for "Earth"
showing 10 items of 12204 documents
Raw material, gestures, artefacts. An approach to the work of bone and ivory in the Iron Age in the Iberian peninsula
2018
Abstract This work seeks to give visibility to the industry of hard animal materials that is documented during the Iron Age in the Iberian peninsula. We focus on the analysis of three common artefacts within the bone and ivory industry in the Iberian culture (between the 6th to the 1st Century BC): pins, perforated plates and combs. We have studied these objects from a technological point of view, thanks to a series of experimental work carried out in order to meet different operational chains, necessary to manufacture each one of these items and tools that could be used for this purpose. So, we searched the archaeological tool models to work bone and ivory, and whenever it has been possibl…
Seasonal and habitat effects on the nutritional properties of savanna vegetation: Potential implications for early hominin dietary ecology.
2019
The African savannas that many early hominins occupied likely experienced stark seasonality and contained mosaic habitats (i.e., combinations of woodlands, wetlands, grasslands, etc.). Most would agree that the bulk of dietary calories obtained by taxa such as Australopithecus and Paranthropus came from the consumption of vegetation growing across these landscapes. It is also likely that many early hominins were selective feeders that consumed particular plants/plant parts (e.g., leaves, fruit, storage organs) depending on the habitat and season within which they were foraging. Thus, improving our understanding of how the nutritional properties of potential hominin plant foods growing in mo…
A large temnospondyl humerus from the Rhaetian (Late Triassic) of Bonenburg (Westphalia, Germany) and its implications for temnospondyl extinction
2018
Temnospondyls are a group of basal tetrapods that existed from the Early Carboniferous to the Early Cretaceous. They were characteristic members of Permian and Triassic continental faunas around the globe. Only one clade, the Brachyopoidea (Brachyopidae and Chigutisauridae), is found as relics in the Jurassic of eastern Asia and the Cretaceous of Australia. The other Late Triassic clades, such as Plagiosauridae, Metoposauridae, and Cyclotsauridae, are generally believed to have gone extinct gradually before the end of the Triassic and putative Rhaetian records are stratigraphically poorly constrained. Temnospondyl humeri all show a similar morphological pattern, being stout, short, with wid…
Translating taxonomy into the evolution of conodont feeding ecology
2016
Conodont research has long been divided between utilitarian applications to solve geological problems versus analysis of their palaeobiology. However recent advances in conodont functional analysis allow these independent stands of research to be unified, decoding the functional implications of their morphological variation. We demonstrate this using synchrotron tomography and Finite Element Analysis, informed by occlusal and microwear analyses, to analyze functionally the classic evolutionary sequence of the genus Polygnathus. Our study shows that the evolution of the platform in Polygnathus occurred to accommodate and dissipate the stress accumulation derived from the tooth-like function …
REWORKING OF FUSULINIDS AND CALCIPHAERIDS IN THE LERCARA FORMATION (SICILY, ITALY); GEOLOGICAL IMPLICATIONS
2004
Different fusulinids have been identified in the Lercara Formation (Sicily). They are: Reichelina sp., Schubertella paramelonica, Toriyamaia (?) sp., Neofusulinella lantenoisi, Yangchienia compressa, Rauserella staffi, Darvasites contractus, Chalaroschwagerina (Taiyuanella?) aff. davalensis, Levenella aff. evoluta, Pamirina darvasica, and Neoschwagerina ex gr. craticulifera. Small Permian foraminifers, as well as the calcispherid Asterosphaera pulchra also exist. The microfossils indicate reworking of different Permian stages, at different periods of time, and possibly also of the Mississippian (Early Carboniferous). All these resediments have been deposited within the Lercara Formation, a …
Flore du Jurassique basal de la ville de Mende (Lozère) : synthèse des gisements historiques, nouvelles données sédimentologiques, paléontologiques e…
2019
Resume Au cours du XXe siecle, la majorite des sites a plantes fossiles (Hettangien–Sinemurien) de la ville de Mende ont disparu a cause d’une importante urbanisation ou bien sont tombes dans l’oubli. Cet article presente une synthese des gisements a vegetaux fossiles, depuis leur decouverte au XIXe siecle jusqu’aux campagnes de prospection recentes. De nouvelles donnees lithostratigraphiques et paleobotaniques sont apportees pour deux sites historiques (le Ravin del Pouset et le Petit Seminaire), ainsi que deux localites fossiliferes dernierement decouvertes (route du Causse-d’Auge et route de Gardes). Cette etude revele la diversite des lithofacies contenant les plantes (dolomudstone, mar…
La radiation des échinodermes au Paléozoïque inférieur, l'exemple des blastozoaires.
2009
10 pages; Le sous-phylum Blastozoa est un des groupes d'échinodermes les plus diversifiés (dix classes) au début du Paléozoïque. Après révision critique de leur squelette, leurs morphologies en apparence très variées sont en fait homogènes. Leur diversité montre deux pics (Drumien, Sandbien) liés par un événement de fortes apparitions génériques au Cambrien supérieur-Ordovicien inférieur. Les blastozoaires montrent un fort endémisme au Cambrien et un important provincialisme à l'Ordovicien inférieur et moyen. Ils deviennent cosmopolites à l'Ordovicien supérieur, par plusieurs événements migratoires. Ils sont restreints à la Laurentia et à Baltica au Silurien inférieur.
Rhinocerotid tooth enamel 18O/16O variability between 23 and 12 Ma in southwestern France.
2006
Abstract The relationship between the oxygen isotope ratio of mammal tooth enamel and that of drinking water was used to reconstruct changes in the Miocene oxygen isotope ratio of rainfall (meteoric water δ 18 O MW ). These, in turn, are related to climatic parameters (temperature, precipitation and evaporation rate). δ 18 O values of rhinocerotid teeth from the Aquitaine Basin (southwestern France) suggest a significant climatic change between 17 and 12 Ma, characterized by cooling together with precipitation increase, in agreement with other terrestrial and oceanic records. To cite this article: I. Bentaleb et al., C. R. Geoscience 338 (2006).
The Use of Medicinal Clay from Silesia “Terra sigillata Silesiaca”, Central Europe - A New Chance for Natural Medicine?
2019
Silesia is a region in Central Europe with beneficial conditions for the presence of clay, including those with potential therapeutic efficacies, due to its very diverse and mosaic geological landscape. The first use of clay deposits in medicine in Silesia, “terra sigillata Silesiaca”, has been dated to 1550 AD, and the oldest written information related to this use has been dated to 1586 AD. Medicinal clay is formed by the accumulation of a mixture of minerals such as smectite, bentonite, montmorillonite, kaolinite, illite, and metahaloisite, with impurities of other minerals and fractions, resulting from the chemical weathering of rocks and the sedimentation of detritus. The quantitative …
The Late Ordovician glacial sedimentary system of the North Gondwana platform.
2009
International audience; The Late Ordovician (Hirnantian) glaciation is examined through the North Gondwana record. This domain extended from southern high palaeo-latitudes (southeastern Mauritania, Niger) to northern lower palaeo-latitudes (Morocco, Turkey) and covered a more than 4000 km-wide section perpendicular to ice-flow lines. A major mid-Hirnantian deglaciation event subdividing the Hirnantian glaciation in two first-order cycles is recognised. As best illustrated by the glacial record in western Libya, each cycle comprises 2-3 glacial phases separated by ice-front retreats several hundreds kilometres to the south. From ice-proximal to ice-distal regions, the number of glacial surfa…