La poix utilisée pour l’étanchéité du bateau. L’apport de l’étude du contenu en pollen et en spores de champignons coprophiles des matériaux d’étanchéité du chaland d’Arles-Rhône 3

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Pollens et charbons de bois de la Grotte Mandrin. Quelques données sur la végétation de la moyenne vallée du Rhône au cours de l’OIS 3

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Pollens et charbons de bois de la Grotte Mandrin - Quelques données sur la végétation de la moyenne vallée du Rhône au cours de l’OIS 3

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Pollen analysis of present-day striped hyaena (Hyaena hyaena) scats from central Iran: Implications for dryland paleoecology and animal paleoethology

International audienceThe striped hyena is the largest living omnivorous scavenger in SW Asia. It generally lives in semi-arid desert steppe regions, often denning in small caves, rock shelters, and burrows close to human settlements. Bone fragments of wild and domestic animals and desiccated scats are frequently found in the hyena dens. In this study, eight striped hyena desiccated scats were subjected to pollen analysis. All scats were rich in pollen and the exine was well-preserved with no visible sign of corrosion. Pollen spectra revealed interesting information on the regional and local vegetation, as well as the foraging behavior and diet of the animal. They reflected an array of different landscapes ranging from natural/semi-natural xerophytic desert steppes, agricultural fields, and grazing pastures. Some scats contained certain pollen taxa very rarely observed in wetland sediments, indicating the high potential of hyena "copropalynology"in providing detailed information on the past floristic composition of the landscape. When comparing with archeobotanical data from the area, the hyena scat assemblages show that the general physiognomy of the landscape has remained almost unchanged since the 6th millennium B.C., with only minor changes in the composition or density of the woody components of the desert steppe. As most of the Holocene fossil coprolites in archeological and paleontological sites of SW Asia would have been left by striped hyena, the study of the modern analogs of such accumulations in extant hyena dens is helpful to correctly interpret the fossil faunal assemblages to reconstruct the paleolandscapes, land-use change, and animal paleoethology

Multiproxy palaeoenvironmental reconstruction of the Bathonian Castelbouc sauropod tracksite (Causses Basin, southern France): insight into a Middle Jurassic insular ecosystem

International audienceWe report lignitic fossil rich-beds from the Bathonian Castelbouc sauropod tracksite (Castelbouc Cave N°4, Causses Basin, southern France). Showing the co-occurrence of amber with plant, vertebrate and invertebrate remains, they are a precious tool to reconstruct Middle Jurassic dinosaur ecosystems. A multiproxy approach combining sedimentology, petrology, mineralogy and palaeontology led to determine that these fossil rich-beds were deposited in a range of insular coastal palaeoenvironments. They include protected backshore areas such as freshwater/brackish ponds and brackish bay/lagoon showing co-occurrence of terrestrial and marine inputs. The backshore environments were particularly rich in ostracods (Darwinula sp., Fabanella bathonica) and gyrogonites of charophytes (Porochara douzensis). The abundance of conifer remains including leafy axes (Brachyphyllum), cones (cf. Classostrobus), wood (Brachyoxylon) and pollen grains (Classopollis) shows that ponds and bay/lagoon were bordered by conifer-dominated forests in which Cheirolepidiaceae were the main component. Such a rich and relatively diverse flora was probably an attractive source of food for megaherbivorous dinosaurs. Vertebrate microremains mostly consist of fish scales (Ginglymodi indet.) and crocodylomorph teeth (Atoposauridae indet.), two groups that are common components of Middle Jurassic paralic faunas. The palaeobotanical assemblage suggests a warm subtropical climate probably tropophilous with marked alternation between a wet and a dry season