نبذة مختصرة : The phenomenon of evolutionary convergence is a fascinating process in which distantly related species independently acquire similar characteristics in response to similar selective pressures. Ant- and termite-eating mammals are among the most famous examples of morphological convergence. Indeed, this particular lifestyle evolved in five distinct lineages of mammals: the aardvark (Tubulidentata), the aardwolf (Carnivora), the anteaters (Pilosa), the giant armadillo (Cingulata), and the pangolins (Pholidota). To better undestand the evolution of these organisms, several approaches were developed in this thesis. First, I present an original strategy to characterize the precise diet of myrmecophagous mammals taking advantage of metagenomic sequencing data generated from fecal samples and a reference mitogenomic database of termites and ants. Second, with the final objective of detecting molecular convergence at the genomic scale in ant-eating mammals, we generated nine high quality mammlian genomes using Oxford Nanopore technologies. The different strategies developed from the set-up of MinION qesuencing to annotation of the resulting assemblies are presented together with a first case study illustrating the use of two of these new reference genomes for species delineation. Finally, I present comparative transcriptomic analyses of salivary glands and other organs in ant-eating mammals suggesting that historical contingency and molecular evolutionary tinkering of chitinase genes played a major role in the convergent evolution of myrmecophagy. ; Le phénomène de convergence évolutive est un processus fascinant dans lequel des espèces phylogénétiquement éloignées acquièrent indépendamment des caractéristiques similaires en réponse à des pressions de sélection similaires. Les mammifères myrmécophages figurent parmi les exemples les plus célèbres de convergence morphologique. En effet, ce mode de vie particulier a évolué chez cinq lignées distinctes de placentaires : l'oryctérope (Tubulidentata), le protèle (Carnivora), ...
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