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1.
PLoS One ; 10(8): e0134231, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26287486

RESUMO

The Velaux-La Bastide Neuve fossil-bearing site (Bouches-du-Rhône, France) has yielded a diverse vertebrate assemblage dominated by dinosaurs, including the titanosaur Atsinganosaurus velauciensis. We here provide a complete inventory of vertebrate fossils collected during two large-scale field campaigns. Numerous crocodilian teeth occur together with complete skulls. Pterosaur, hybodont shark and fish elements are also represented but uncommon. Magnetostratigraphic analyses associated with biostratigraphic data from dinosaur eggshell and charophytes suggest a Late Campanian age for the locality. Lithologic and taphonomic studies, associated with microfacies and palynofacies analyses, indicate a fluvial setting of moderate energy with broad floodplain. Palynomorphs are quite rare; only three taxa of pollen grains occur: a bisaccate taxon, a second form probably belonging to the Normapolles complex, and another tricolporate taxon. Despite the good state of preservation, these taxa are generally difficult to identify, since they are scarce and have a very minute size. Most of the vertebrate remains are well preserved and suggest transport of the carcasses over short distances before accumulation in channel and overbank facies, together with reworked Aptian grains of glauconite, followed by a rapid burial. The bones accumulated in three thin layers that differ by their depositional modes and their taphonomic histories. Numerous calcareous and iron oxides-rich paleosols developed on the floodplain, suggesting an alternating dry and humid climate in the region during the Late Campanian.


Assuntos
Osso e Ossos , Fósseis , Vertebrados , Jacarés e Crocodilos/anatomia & histologia , Animais , Evolução Biológica , Osso e Ossos/anatomia & histologia , Dinossauros/anatomia & histologia , Meio Ambiente , Peixes/anatomia & histologia , Fósseis/anatomia & histologia , Paleontologia/métodos , Crânio/anatomia & histologia , Dente/anatomia & histologia , Vertebrados/anatomia & histologia
2.
Nature ; 418(6894): 145-51, 2002 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-12110880

RESUMO

The search for the earliest fossil evidence of the human lineage has been concentrated in East Africa. Here we report the discovery of six hominid specimens from Chad, central Africa, 2,500 km from the East African Rift Valley. The fossils include a nearly complete cranium and fragmentary lower jaws. The associated fauna suggest the fossils are between 6 and 7 million years old. The fossils display a unique mosaic of primitive and derived characters, and constitute a new genus and species of hominid. The distance from the Rift Valley, and the great antiquity of the fossils, suggest that the earliest members of the hominid clade were more widely distributed than has been thought, and that the divergence between the human and chimpanzee lineages was earlier than indicated by most molecular studies.


Assuntos
Evolução Biológica , Fósseis , Hominidae/anatomia & histologia , Hominidae/classificação , Animais , Chade , História Antiga , Humanos , Arcada Osseodentária/anatomia & histologia , Masculino , Pan troglodytes/anatomia & histologia , Crânio/anatomia & histologia , Especificidade da Espécie , Fatores de Tempo , Dente/anatomia & histologia
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