Sandrine LADEVEZE

As a paleontologist and biologist, I am particularly interested in all topics dealing with evolutionary morphology and paleobiology of mammals. More peculiarly, my research focuses on marsupials as a model for studying the evolution and development of complex anatomical structures in mammals.

Evolutionary biologists have a unique approach of the living that allows them, through the reconstruction of evolutionary histories, to address a major question: what are the mechanisms of the biological evolution? However, they only dispose of lacunary data, since 99% of the biodiversity is extinct. That is the reason why fossils are crucial. They bring an historical framework, they document morphological diversity through evolutionary sequences, and they can reveal a spectacular range in size, shape, and adaptations.

The paleogeographic context is also crucial because the reconstruction of evolutionary histories within this framework will permit a better comprehension of the morphological evolution submitted to geographic and environmental constraints, and finally developmental constraints.

Only a few of the biological groups have fossil records that chronicle their evolutionary past. One of these few is Metatheria (marsupial mammals), the fossil record of which is particularly abundant.

Once set a comprehensive phylogenetic and paleogeographic framework, fundamental questions on evolutionary biology can be addressed; for instance:

• Is the opossum a good model as ancestral condition of therian mammals?
• What are the mechanisms of the morphological diversity in the mammalian skull and teeth?