Roles of dental development and adaptation in rodent evolution

Helder Gomes Rodrigues (1) , Sabrina Renaud (2) , Cyril Charles (3) , Yann Le Poul (4) , Floréal Solé (5) , Jean-Pierre Aguilar (6) , Jacques Michaux (6) , Paul Tafforeau (7) , Denis Headon (8) , Jukka Jernvall , Laurent Viriot (3)

1 CR2P - Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements
2 Ecologie et évolution des populations
3 IGFL - Institut de Génomique Fonctionnelle de Lyon
4 ISYEB - Institut de Systématique, Evolution, Biodiversité
5 RBINS - Royal Belgian Institute of Natural Sciences
6 UMR ISEM - Institut des Sciences de l'Evolution de Montpellier
7 ESRF - European Synchrotron Radiation Facility
8 The Roslin Institute and Royal School of Veterinary Studies

In paleontology, many changes affecting morphology, such as tooth shape in mammals, are interpreted as ecological adaptations that reflect important selective events. Despite continuing studies, the identification of the genetic bases and key ecological drivers of specific mammalian dental morphologies remains elusive. Here we focus on the genetic and functional bases of stephanodonty, a pattern characterized by longitudinal crests on molars that arose in parallel during the diversification of murine rodents. We find that overexpression of Eda or Edar is sufficient to produce the longitudinal crests defining stephanodonty in transgenic laboratory mice. Whereas our dental microwear analyses show that stephano-donty likely represents an adaptation to highly fibrous diet, the initial and parallel appearance of stephanodonty may have been facilitated by developmental processes, without being necessarily under positive selection. This study demonstrates how combining development and function can help to evaluate adaptive scenarios in the evolution of new morphologies.

Domaines: Evolution [q-bio.PE]

Helder Gomes Rodrigues, Sabrina Renaud, Cyril Charles, Yann Le Poul, Floréal Solé, et al.. Roles of dental development and adaptation in rodent evolution. Nature Communications, 2013, 4 (1), ⟨10.1038/ncomms3504⟩. ⟨hal-02337534⟩