References of "Bardet, Nathalie"
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See detailMary Anning’s legacy to French vertebrate palaeontology
Vincent, Peggy; Taquet, Philippe; Fischer, Valentin ULg et al

in Geological Magazine (2014), 151(1), 7-20

The real nature of marine reptile fossils found in England in between the 1700s to the beginning of the 1900s remained enigmatic, until Mary Anning's incredible fossil discoveries and their subsequent ... [more ▼]

The real nature of marine reptile fossils found in England in between the 1700s to the beginning of the 1900s remained enigmatic, until Mary Anning's incredible fossil discoveries and their subsequent study by eminent English and French scientists. In 1820, Georges Cuvier acquired several ichthyosaur specimens found by Mary Anning, now kept or displayed in the Palaeontology Gallery of the MNHN in Paris. Four years later, Cuvier obtained a plesiosaur specimen from Mary Anning, only the second ever discovered. Cuvier was fascinated by these fossils and their study allowed him to apply his comparative anatomical method and to support his catastrophist theory. We re-examined these important specimens from an historical point of view and herein describe them taxonomically for the first time since Cuvier’s works. The Paris specimens belong to two different ichthyosaur genera (Ichthyosaurus and Leptonectes) and one plesiosaur genus (Plesiosaurus). [less ▲]

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See detailHigh Diversity in Cretaceous Ichthyosaurs from Europe Prior to Their Extinction
Fischer, Valentin ULg; Bardet, Nathalie; Guiomar, Myette et al

in PLoS ONE (2014), 9(1), 84709

Background: Ichthyosaurs are reptiles that inhabited the marine realm during most of the Mesozoic. Their Cretaceous representatives have traditionally been considered as the last survivors of a group ... [more ▼]

Background: Ichthyosaurs are reptiles that inhabited the marine realm during most of the Mesozoic. Their Cretaceous representatives have traditionally been considered as the last survivors of a group declining since the Jurassic. Recently, however, an unexpected diversity has been described in Upper Jurassic–Lower Cretaceous deposits, but is widely spread across time and space, giving small clues on the adaptive potential and ecosystem control of the last ichthyosaurs. The famous but little studied English Gault Formation and ‘greensands’ deposits (the Upper Greensand Formation and the Cambridge Greensand Member of the Lower Chalk Formation) offer an unprecedented opportunity to investigate this topic, containing thousands of ichthyosaur remains spanning the Early–Late Cretaceous boundary. Methodology/Principal findings: To assess the diversity of the ichthyosaur assemblage from these sedimentary bodies, we recognized morphotypes within each type of bones. We grouped these morphotypes together, when possible, by using articulated specimens from the same formations and from new localities in the Vocontian Basin (France); a revised taxonomic scheme is proposed. We recognize the following taxa in the ‘greensands’: the platypterygiines ‘Platypterygius’ sp. and Sisteronia seeleyi gen. et sp. nov., indeterminate ophthalmosaurines and the rare incertae sedis Cetarthrosaurus walkeri. The taxonomic diversity of late Albian ichthyosaurs now matches that of older, well-known intervals such as the Toarcian or the Tithonian. Contrasting tooth shapes and wear patterns suggest that these ichthyosaurs colonized three distinct feeding guilds, despite the presence of numerous plesiosaur taxa. Conclusion/Significance: Western Europe was a diversity hot-spot for ichthyosaurs a few million years prior to their final extinction. By contrast, the low diversity in Australia and U.S.A. suggests strong geographical disparities in the diversity pattern of Albian–early Cenomanian ichthyosaurs. This provides a whole new context to investigate the extinction of these successful marine reptiles, at the end of the Cenomanian. [less ▲]

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See detailMesozoic marine reptile palaeobiogeography in response to drifting plates
Bardet, Nathalie; Fischer, Valentin ULg; Houssaye, Alexandra et al

Conference (2012, September)

Mesosaurus Broom, 1913, from the Early Permian, is the first aquatic reptile known in the fossil record. Its co-occurrence in both South Africa (South Africa) and South America (Brazil, Uruguay) made it ... [more ▼]

Mesosaurus Broom, 1913, from the Early Permian, is the first aquatic reptile known in the fossil record. Its co-occurrence in both South Africa (South Africa) and South America (Brazil, Uruguay) made it one of the key-fossils - with the pteridospermatophyta plant Glossopteris - used by the German meteorologist / geophysician Alfred Wegener to support his theory of the Continental Drift (Kontinentalverschiebung), first published in 1912. But Mesosaurus was only the “tip of the iceberg” as, during the Mesozoic, various clades of reptiles massively invaded the aquatic, and more especially, the marine realm. They were highly diversified both systematically and ecologically, and some of them were large top-predators of the marine ecosystems. The main groups were, in order of appearance in the fossil record, Ichthyosauria (earliest Triassic – early Late Cretaceous), Sauropterygia (nothosaurs, pachypleurosaurs, placodonts, plesiosaurs; Early Triassic – latest Cretaceous), Thalattosauria (Middle-Late Triassic), Pleurosauria (Early Jurassic–Early Cretaceous), as well as, among others, several lineages of Chelonians (e.g. chelonioids, bothremydids, “thalassemyds”), Crocodyliformes (thalattosuchians, dyrosaurids, pholidosaurids, gavialoids) and Squamates (mosasauroids, “dolichosaurs”, marine snakes). During the Mesozoic, the palaeobiogeographical distributions and the dispersion events of these marine reptiles closely followed the break-off of the Pangea induced by plate tectonic movements. Although marine reptiles can help in determining the possible date of opening of marine corridors, the information they provide are less precise than that delivered by terrestrial faunas, as the marine realm is a more open system and various migration ways are always possible. Generally, the Triassic taxa were animals with a restricted palaeobiogeographical distribution living near the coastlines of the Pangea. From the end of the Triassic and during the Jurassic, the break-off of the Pangea resulted in the formation of large marine corridors, allowing open-sea marine reptiles such as ichthyosaurs, plesiosaurs and crocodyliformes to spread out over large distances. As an example, similar marine reptile faunas are known from the Jurassic of Europe and southern South America, as a result of dispersion events via the Hispanic Corridor that connected the Tethys / North Atlantic and Pacific realms at this time. During the Cretaceous, and notably with the expansion of the Atlantic Ocean, most of these reptiles were cosmopolite and open-sea forms (plesiosaurs, mosasaurid squamates, chelonioid turtles). However, even if large faunal interchanges were possible, some provinces such as the Northern and Southern margins of the Tethys were characterized by a peculiar faunal identity, notably concerning mosasaurids, despite the apparent absence of barriers. So, if Continental Drift enabled circulation and faunal interchanges, other parameters such as ecological constraints probably also played a role in the distribution of these marine reptile faunas. [less ▲]

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See detailExtinctions et renouvellements fauniques chez les reptiles marins du Crétacé
Bardet, Nathalie; Fischer, Valentin ULg; Jouve, Stéphane et al

Conference (2011, December)

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