New evidence from the bony labyrinth and teeth of the Late Miocene ape Oreopithecus based on a partial cranium from Baccinello
Urciuoli, Alessandro (Institut Català de Paleontologia Miquel Crusafont)
Zanolli, Clément (Centre National de la Recherche Scientifique. Université de Bordeaux)
Bouchet, Florian (Institut Català de Paleontologia Miquel Crusafont)
Arias-Martorell, Julia (Institut Català de Paleontologia Miquel Crusafont)
Costeur, Loïc (Naturhistorisches Museum Basel)
Rook, Lorenzo (Università degli Studi di Firenze. Dipartimento di Scienze della Terra)
Alba, David M. (Institut Català de Paleontologia Miquel Crusafont)

Date:	2026
Abstract:	Oreopithecus bambolii, from the Tusco-Sardinian archipelago, is the latest-known European Miocene ape and a longstanding evolutionary enigma, owing to its mosaic morphology. Its systematic position has been intensely debated, resulting in a broad spectrum of hypotheses, ranging from a dryopithecine great ape to a nyanzapithecid stem hominoid, a giant hylobatid, or even a pliopithecoid. We reassess these competing hypotheses based on new data from the bony labyrinth and teeth of a partial cranium (Bac 62) from Baccinello (8. 3-7. 7 Ma). Diffeomorphic deformation analysis of the semicircular canals (SCs) and vestibule, dental tissue proportions, and enamel-dentine junction shape were used to compare Oreopithecus with a sample of extant and extinct anthropoids. Our results confirm that the SCs and vestibule of Oreopithecus combine some derived crown hominoid synapomorphies and crown hylobatid-like characters with the retention of anthropoid symplesiomorphies that preclude a straightforward classification. In turn, the enamel-dentine junction shape of the upper molars markedly differs from that of dryopithecines and extant hominoids but only shows some similarities with that of pliopithecoids, while the analysis of tooth tissue proportions reveals thick enamel. Our results, combined with previous evidence based on cranial morphology, strongly argue against a close phylogenetic relationship with Miocene apes from Europe and do not particularly support a close relationship with hylobatids. Instead, they are more consistent with Oreopithecus being a derived stem hominoid, although the scarce available data for nyanzapithecids precludes adequately testing this hypothesis and some similarities with pliopithecoids remain intriguing and deserve further investigation.
Grants:	Agencia Estatal de Investigación PID2024-159434NB-I00 Agencia Estatal de Investigación PID2020-116908GB-I00 Agencia Estatal de Investigación PID2020-117289GB-I00 Generalitat de Catalunya 2022/SGR-00620 Generalitat de Catalunya 2022/SGR-01188
Note:	Altres ajuts: CERCA Programme/Generalitat de Catalunya
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Enamel-dentine junction ; Evolution ; Geometric morphometrics ; Hominoidea ; Phylogeny ; Semicircular canals
Published in:	Journal of Mammalian Evolution, Vol. 33, Num. 1 (March 2026) , art. 6, ISSN 1573-7055

DOI: 10.1007/s10914-025-09793-0

24 p, 6.0 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Institut Català de Paleontologia Miquel Crusafont (ICP)
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