Taxonomy, phylogeny and biogeography of myrmicine ants : insight from Cenozoic fossils

• Main Author: Chény, Cédric
• Other Authors: Géosciences Rennes (GR), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Université Rennes 1, Vincent Perrichot, Bo Wang
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: HAL CCSD 2020
• Subjects: Formicidae; Myrmicinae; Taxonomy; Phylogeny; Biogeography; Cenozoic; Taxonomie; Phylogénie; Biogéographie; Cénozoïque; [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology; Greenland; Antarc*; Antarctica; Beringia
• Online Access: https://tel.archives-ouvertes.fr/tel-03228593; https://tel.archives-ouvertes.fr/tel-03228593/document; https://tel.archives-ouvertes.fr/tel-03228593/file/CHENY_Cedric.pdf

With more than 7000 species, the myrmicine ants constitutes one of the most successful ecological successes in history. Yet, their evolutionary history remains poorly understood. The present work attempts to trace their evolution through the taxonomic study of recent discoveries of fossil myrmicines (Eocene Oise amber, Miocene Zhangpu and Ethiopian amber), in order to use them as new calibration points.The approach combines the most recent data-processing tools that allow a better consideration of palaeontological data (diversification, sampling rate, etc.), and their integration into phylogenetic analysis (FBD model, CladeAge). The effect of various calibration modes (root node calibration, crown- or stem- calibration, distribution models, node-dating vs. tip-dating) on divergence dating estimates is also tested and discussed. Finally, the biogeographical history is reviewed in the light of new occurrences and phylogenetic results. The group would have appeared in the New World during Upper Cretaceous (85-95 Ma), but without clearly indicating a stronger affiliation to Nearctic or Neotropic. The major lineages would have quickly spread out across the globe, particularly during Eocene through Antarctica, Beringia and Greenland. The extension of tropical latitudes following hyperthermal events (ETM, MECO) would have led to successive dispersions between New World and Old World, and would explain the apparent disparity of actual distributions. The basal lineages are respectively restricted to the Nearctic-Palearctic and the New World, while the more derived lineages show wider but also more heterogeneous distributions. Avec plus de 7000 espèces, les fourmis Myrmicinae constituent l’un des plus grands succès écologiques de l’histoire. Pourtant, leur histoire évolutive reste mal comprise. Le présent travail tente de retracer l’évolution du groupe, par l’étude taxonomique des récentes découvertes de myrmicines fossiles (ambre éocène de l’Oise, ambre miocène de Zhangpu et d’Éthiopie), pour les utiliser comme ...