One of the aims of palaeontology is to understand the mechanisms by which species evolved. In order the achieve this, it probes the diverse conditions of their adaptations, among which are the modalities of ontogenetic development, anatomical and functional characters, and more generally, their positions within past ecosystems. Thanks to the development of powerful new analytical techniques, this approach is increasingly becoming a major trend in the study of function and ecology in fossil organisms.
In this context, our team of researchers and lecturer-researchers ( Equipe 2F " Forms and Functions") undertakes palaeobiological studies within a broad framework which combines three axes of research focussed on the main clades of vertebrates over a vast time span (Silurian to Pliocene). The principal tools and methods employed are anatomy, phylogeny, biomechanics, histology, 3D imagery and morphometry.
Perception of environment and development of sense organs (Directors: Philippe Janvier, Stéphane Peigné)
The way in which organisms perceive their environment is an essential ingredient in their evolution and adaptations to the surrounding environment. Perception of the environment and locomotion in extant species are narrowly linked to the central nervous system and the sense organs (hearing, balance, vision, olfaction, etc.). Whereas these organs and their sensorial functions are well known to biologists who study the anatomical, neurological, physiological and functional aspects, palaeontologists are handicapped because the fossil record preserves only bony or calcified structures, which nevertheless sometimes yield indirect evidence or provide analogies with extant forms. As a result, few of these structures have been studied from the point of view of neuroanatomy, physiology, function and evolution. This project therefore aims to focus on these sense organs and on the structures related to perception and to orientation of the organism in space.
Terrestrialisation and return to aquatic life in the evolution of Vertebrates (Directors : Gaël Clément, Jean-Sébastien Steyer)
In the history of vertebrates, terrestrialisation (classically defined as the "emergence onto land") as well as the subsequent return of abundant taxa to an aquatic life, represent major evolutionary events affecting all aspects of the biology of the organisms concerned. These two processes need to be explored in depth, because the adaptations present in the two groups implicate the same basic functions (locomotion, reproduction, feeding, respiration, perception of the environment etc.) and for some of them, similar, but opposed, constraints can intervene. The project, aided by 2D and 3D technologies, and by a reference Palaeohistotheque (collection of thin sections showing fossil cell structures) intends to : 1) fully document the modifications that affected the anatomy, physiology and ecology of the taxa concerned during the course of their evolutionary history; 2) explore the biological mechanisms which could have intervened during the installation of these modifications; 3) determine their adaptive significance and their ecological consequences.
Locomotion (Directors: Christine Argot, Marc Godinot)
Locomotor adaptations are essential for the majority of animals in all environments. Whereas extreme and specialised adaptations are readily identified and are in general well understood, there remain many questions concerning the beginnings of adaptations, mixed adaptations, adaptations in poorly known groups, or ancient adaptations. Thus, in Palaeogene mammals of which the morphology was “generalised”, close to that of the ancestral morphotype, one can legitimately question what environment and life mode they were adapted to. Several issues need examination in order to yield evidence which is essential for understanding the evolution of various groups. The study of locomotor adaptations uses an approach combining comparative and functional anatomy. In this project the aim is to focus on problems linked to terrestrial, arboreal and marine locomotion among diverse groups of Palaeogene mammals.
Researchers and Lecturer-researchers
Christine Argot, Nathalie Bardet, Gaël Clément, Damien Germain, Marc Godinot, Sandrine Ladevèze, Stéphane Peigné, Alain Pradel, Jean-Sébastien Steyer, Peggy Vincent
Emeritus research scientist
Research post-graduates associates and Doctoral students
Remi Allemand, Thomas Arbez, Christine Bohmer, Margot Michaud, Rohan Mansuit, Martial Plasse, Charlène Selva, Séverine Toussaint
Publié le : 13/12/2017 à 17:51 - Mis à jour le : 13/12/2017 à 17:55