Full title: Macroevolutionary pattern of belemnites (Mollusca, Cephalopoda) from the Lower Jurassic: a multidisciplinary approach.
Abstract
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It is now widely assumed that the current erosion of biodiversity is a significant phenomenon in Earth’s history. Understanding the dynamics of past extinctions seems crucial if we are to put the attrition of biodiversity into perspective. Since the pioneering work of Raup & Sepkoski, many palaeontological studies examined the role of extinction selectivity on macroevolutionary patterns in relation to the geographical range, life-span, morphology and ecology of taxa. Palaeontology tends to adopt an approach of methodological uniformitarianism by appealing to causes observable at the present time, before seeking extraordinary explanations for observed evolutionary patterns.
The present project basically aims to contribute to this topic, using paleontological data as palaeobiodiversity model. Its main interest is to explore biodiversity through time, which is obviously not possible for present taxa based studies. The present project focuses on belemnites (Mollusca, Cephalopoda), which have surprisingly never been studied in this context, and will focus on the Pliensbachian–Toarcian period (~190–175 Ma), which encompassed one of the most important marine crises of the Mesozoic, affecting groups such as ostracods, foraminifers and ammonites.
The present project will investigate the following questions:
- What are the main macroevolutionary patterns of belemnites during this period?
- Are there any biogeographical pattern changes during the studied period?
- What are the palaeoenvironmental and biological triggers of macroevolutionary and biogeographical changes?
- Are the patterns different from those observed for other taxa, and specially ammonites?
However, reaching these main objectives imply to get a good knowledge of belemnites species for the studied period. Recent results based on taxonomic revision or quantification of intra- and interspecific variations call for a reappraisal of species, particularly taking into account shape variation for their recognition. For this reason, the present project explicitly includes a first step of basic studies of belemnites in order to get a homogeneous database, based on a reappraisal of species. This is the first objective to reach before addressing macroevolutionary questions.
Finally, these nektonic cephalopods, are widely used to constrain palaeoenvironments using the isotopic signal of their rostrum. A reappraisal of species definition, and a better knowledge of their ecology will obviously conduct to have a fresh view on geochemistry interpretation.
Status of PhD
Supervisor at university: Prof. Dr. Pascal Neige, Laboratory Biogeosciences (UMR CNRS/uB 5561), University of Burgundy, Dijon.
Supervisor in Luxembourg: Robert Weis, Paleontological Department, National Museum for Natural History, Luxembourg.
PhD granted by Fonds national de la recherche Luxembourg. Duration: 3 years (01.03.2012 – 28.02.2015).
Host institution: Fondation faune-flore @ Centre de recherche scientifique, Musée national d’histoire naturelle.
Contact
Jean-Daniel Pinard
Musée national d’histoire naturelle
Centre de recherche scientifique
Laboratoire/Section de Paléontologie
24, rue Münster
L-2160 Luxembourg
phone: (+352) 462240-203
fax: (+352) 463848
jeandaniel.pinard@mnhn.lu
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Publications and not published works
- Pinard, J.D., 2010. Biometric and morphometric study of a population of Youngibelus (Belemnitida) from early Toarcian (Lower Jurassic). 1st year Master-thesis, University of Burgundy (Dijon).
- Pinard, J.D., 2011. Morphological quantification and isotopic analysis of a belemnites assemblage from Toarcian (Lower Jurassic). Master-thesis, University of Burgundy (Dijon).
- Pinard, J.D. & Neige, P., 2011. Morphological quantification of belemnites rostra, Toarcian (Lower Jurassic). Abstract volume of the 4th International Symposium Coleoid Cephalopods Through Time.
Talks and poster presentations
- Pinard, J.D. & Neige, P. (2011). Morphological quantification of belemnites rostra, Toarcian (Lower Jurassic). Poster presentation during the 4th International Symposium Coleoid Cephalopods Through Time, Stuttgart, sept. 2011