1. New Middle Eocene proboscidean from Togo illuminates the early evolution of the elephantiform-like dental pattern
- Author
-
Anne-Lise Charruault, Frédéric Quillévéré, Koffi Evenyon Kassegne, Guillaume Guinot, Ampah Kodjo C. Johnson, Rodolphe Tabuce, Lionel Hautier, Yawovi Zikpi Amoudji, Maeva J. Orliac, Mickaël Mourlam, Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS), Université de Lomé [Togo], Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UR226, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École pratique des hautes études (EPHE), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon
- Subjects
0106 biological sciences ,010506 paleontology ,[SDV]Life Sciences [q-bio] ,Hiatus ,010603 evolutionary biology ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,Tooth crown ,Proboscidea ,Genus ,[SDV.BA.ZV]Life Sciences [q-bio]/Animal biology/Vertebrate Zoology ,Phylogeny ,0105 earth and related environmental sciences ,General Environmental Science ,General Immunology and Microbiology ,biology ,Fossils ,[SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE] ,myr ,Elephantiformes ,General Medicine ,biology.organism_classification ,Biological Evolution ,Taxon ,Geography ,Palaeobiology ,Evolutionary biology ,Togo ,General Agricultural and Biological Sciences ,Tooth ,Lutetian - Abstract
Africa has played a pivotal role in the evolution of early proboscideans (elephants and their extinct relatives), yet vast temporal and geographical zones remain uncharted on the continent. A long hiatus encompassing most of the Eocene (Ypresian to the Early Priabonian, around 13 Myr timespan) considerably hampers our understanding of the early evolutionary history of the group. It is notably the case with the origin of its most successful members, the Elephantiformes, i.e. all elephant-like proboscideans most closely related to modern elephants. Here, we describe a proboscidean lower molar discovered in Lutetian phosphate deposits from Togo, and name a new genus and species, Dagbatitherium tassyi . We show that Dagbatitherium displays several elephantiform dental characteristics such as a three-layered Schmelzmuster, the presence of a mesoconid, transversely enlarged buccal cusps and the individualization of a third lophid closely appressed to a minute distal cingulid. Dagbatitherium represents a stem Elephantiformes, pushing back the origin of the group by about 10 Myr, i.e. a third of its currently known evolutionary history. More importantly, Dagbatitherium potentially unlocks the puzzle of the origin of the unique elephantiform tooth crown organization by bridging a critical temporal and morphological gap between early bunodont incipiently bilophodont proboscidean taxa and more derived elephantiforms.
- Published
- 2021
- Full Text
- View/download PDF