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| Reconstruction of Homotherium latidens based on the fossil specimen MNHN.F.PET 2000 a & b from Perrier |
Highlights:
• Previous interpretations have shown sabre-toothed felids with exposed upper canines.
• Our study combining fossils and extant specimens reveals a different life appearance.
• In Homotherium the upper canines had been covered in life when the mouth was closed.
• Smilodon would show visible upper canines when the mouth was closed.
Abstract
Homotherium is one of the sabre-toothed felid genera with a more extensive overlap in space and time with species of our own genus Homo, who must have been familiar with the animal, but now we only have its fossil remains to infer its life appearance. A revised reconstruction of the soft tissue and life appearance of Homotherium latidens is proposed here on the basis of new observations on the anatomy of extant carnivorans and a re-evaluation of the fairly preserved skull and mandible from the classical Late Pliocene site of Perrier (France). This fossil specimen provides some of the best information available about the morphology of the skull and mandible. Like other large early specimens of Homotherium, it has enormous upper canines relative to skull size and high-crowned enough to protrude beyond the lips in the living animal. On the other hand, observations of facial expressions in living big cats and dissected specimens show that, contrary to previous conclusions, the soft tissue around the mouth and the lower lip in particular can cover the upper canines of large felids, even when those are considerably high-crowned. Such observations lead us to propose a revised hypothesis about the life appearance of Homotherium and other sabre-toothed carnivorans, where the upper canines may have been covered in life when the mouth was completely closed.
Keywords: Plio-Pleistocene transition, Paleoclimatology, Global, Data analysis, Paleobiology, Anatomy, Felidae
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| Reconstruction of Homotherium latidens based on the fossil specimen MNHN.F.PET 2000 a & b from Perrier: (A), lateral view of skull and mandible with slight restoration of the ventral outline of the mental crest, and cervical column (this latter a schematic outline based on fossils from Senèze and Incarcal); (B), outline of cranio-cervical skeleton, showing the attachment areas of selected muscles including the temporalis (t), masseter (m), digastric (d) and levator nasolabialis (ln); (C), reconstruction of selected elements of soft-tissue anatomy including the muscles temporalis (t), masseter (m) and digastric (d), as well as the bisected nasal cartilage (nc) and the bisected mass of connective tissue rostroventral to the mental region of the mandible (ctm); (D), reconstruction of the superficial craniocervical musculature, showing fibres of the levator nasolabialis muscle (lnf) and of the orbicularis oris (oof); (E), reconstructed external appearance of the head and neck. (Artwork by M. Antón) |
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| Reconstruction of Homotherium latidens based on the fossil specimen MNHN.F.PET 2000 a & b from Perrier: (A) and (B), perspective view of skull from CT scan, and reconstructed head; (C) and (D), frontal view of idealized virtually sculpted skull and reconstructed head (Artwork by M. Antón). (E) and (F), perspective view with a relaxed expression comparable to that observed in modern tiger (Panthera tigris) shown in Fig. 2J; (G), lateral view of a yawning animal comparable to that observed in modern male lion (Panthera leo) shown in Fig. 2A; (H), lateral view of animal with slightly open jaws and lips contracted in a growling gesture comparable to that observed in modern lioness (Panthera leo) shown in Fig. 2D. (Artwork by M. Antón) |
Mauricio Antón, Gema Siliceo, Juan F. Pastor and Manuel J. Salesa. 2022. Concealed Weapons: A Revised Reconstruction of the Facial Anatomy and Life Appearance of the Sabre-toothed Cat Homotherium latidens (Felidae, Machairodontinae). Quaternary Science Reviews. 284, 107471. DOI: 10.1016/j.quascirev.2022.107471
