The Institute of Biology of the �cole Normale Sup�rieure (Paris, France) is offering a 3-years funded PhD position to explore the topic of molecular-morphological discordance in phylogenetic inference using fossil data. The PhD student will be supervised by Jo�lle Barido-Sottani. This project is funded as part of the MORPHOFBD ERC grant and will start in February 2026 at the earliest. Thesis subject: The fossil record provides crucial evidence to inform our study of evolution and past diversification processes. Recent methodological developments have allowed to integrate fossil species directly into the reconstruction of phylogenetic trees, providing more accurate estimates of the age of evolutionary events as well as speciation and extinction through time. However, the current methods fail to account for many of the specific characteristics of fossil samples compared to extant species. In particular, genetic sequences are usually unavailable for fossils, so phylogenetic inferences including fossils rely on morphological characters. Combining molecular and morphological information into one inference in this way presents a number of challenges. This doctoral project aims to explore one particular challenge: the presence of discordance between morphological and molecular information, a situation in which the two different sources of information support different phylogenetic trees. Discordance can happen due for instance to convergent evolution, where the same phenotype develops independently in different clades which then appears to be closer evolutionarily than they actually are. Expected skills: We are looking for a PhD student with a strong interest for evolutionary processes and good computational skills. Programming experience is a prerequisite, and experience using the programming languages R or Java will be appreciated. Previous experience with phylogenetics will be an advantage but is not required. The candidate must have good communication skills (oral and written) in English, and be able to work in a team on multi-disciplinary projects. To find further details and to apply, please go to https://emploi.cnrs.fr/Offres/Doctorant/UMR8197-VALHER-202/Default.aspx?lang=EN Questions can be addressed to : Jo�lle Barido-Sottani Permanent researcher Institute of Biology, ENS-PSL joelle.barido-sottani@bio.ens.psl.eu Jo�lle Barido-Sottani (to subscribe/unsubscribe the EvolDir send mail to golding@mcmaster.ca)