UNDER PRESSURE? DENTAL ADAPTATIONS TO TERMITOPHAGY AND VERMIVORY AMONG MAMMALS

Authors

  • Cyril Charles,

    Corresponding author
    1. Team Evo-Devo of Vertebrate Dentition, Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, CNRS UMR 5242, UCBL 1, Ecole Normale Supérieure de Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France
    Search for more papers by this author
    • These authors contributed equally to the study.

  • Floréal Solé,

    1. Team Evo-Devo of Vertebrate Dentition, Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, CNRS UMR 5242, UCBL 1, Ecole Normale Supérieure de Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France
    Current affiliation:
    1. Royal Belgian Institute of Natural Sciences, Direction Earth and History of Life Vautierstraat 29, 1000 Brussels, Belgium
    Search for more papers by this author
    • These authors contributed equally to the study.

  • Helder Gomes Rodrigues,

    1. Team Evo-Devo of Vertebrate Dentition, Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, CNRS UMR 5242, UCBL 1, Ecole Normale Supérieure de Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France
    Search for more papers by this author
  • Laurent Viriot

    1. Team Evo-Devo of Vertebrate Dentition, Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, CNRS UMR 5242, UCBL 1, Ecole Normale Supérieure de Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France
    Search for more papers by this author

Abstract

The extant mammals have evolved highly diversified diets associated with many specialized morphologies. Two rare diets, termitophagy and vermivory, are characterized by unusual morphological and dental adaptations that have evolved independently in several clades. Termitophagy is known to be associated with increases in tooth number, crown simplification, enamel loss, and the appearance of intermolar diastemata. We observed similar modifications at the species level in vermivorous clades, although interestingly the vermivorous mammals lack secondarily derived tools that compensate for the dentition's reduced function. We argue that the parallel dental changes in these specialists are the result of relaxed selection on occlusal functions of the dentition, which allow a parallel cascade of changes to occur independently in each clade. Comparison of the phenotypes of Rhynchomys, a vermivorous rat, and strains of mice whose ectodysplasin (EDA) pathway has been mutated revealed several shared dental features. Our results point to the likely involvement of this genetic pathway in the rapid, parallel morphological specializations in termitophagous and vermivorous species. We show that diets or feeding mechanisms in other mammals that are linked to decreased reliance on complex can lead to similar cascades of change.

Ancillary