A human lower third molar from the Acheulean site of Cueva del Ángel (Lucena, Córdoba, Spain)

Abstract

Objectives: To present a new dental specimen that will provide additional evidence for a better understanding of early European Upper Pleistocene hominin morphological variability. Materials and Methods: We described the morphology of this human right lower third molar at both the outer enamel surface and the enamel–dentine junction by means of micro-computed tomography. In order to better understand hominin diversity, our morphological and metrical results were compared with those of other hominins obtained from published research. We provide a direct aspartic acid racemization dating of the molar. Results: The direct dating (104.3 ka) situates the molar within the Marine isotopic stage 5d. The crown dimensions are comparable to those of the Sima de los Huesos sample and modern humans. The combination of a continuous middle trigonid crest and a well-developed anterior fovea lies within the range of morphological variation reported for Neanderthal lower molars. The distal portion of the molar has a prominent protostylid. Discussion: Crown and root morphology of this molar fits within the Neanderthal morphological pattern. However, both its dimensions and the absence of a hypoconulid tend to position this specimen away from contemporaneous Neanderthals and rather relate it more closely to some Middle Pleistocene populations. Conclusions: A new dental specimen is added to the Iberian Peninsula fossil record from the Marine isotopic stage 5, attesting to some degree of dental variability in the early Upper Pleistocene.