Senescence in European Middle Pleistocene hominids: The Atapuerca evidence

The mandibular specimens AT-250 and AT-793 (individual IV) and AT-888 (individual XXI) from the Atapuerca Middle Pleistocene sample show a combination of traits interpreted as evidence of senescence. In order to explore age-related mandibular changes relevant to the interpretation of the Atapuerca hominids, the sample of known age and sex from Spitalfields (London) and the Neolithic sample from Abu Hureyra (Syria) were used as a baseline. Results obtained indicate that the occurrence of an enlarged and posteriorly located mental foramen, in association with high alveolar resorption in AT-250 and AT-888, support the hypothesis of senescence in individuals IV and XXI from the Atapuerca sample. The findings suggest that European Middle Pleistocene populations lived long enough to reach senescence. The age at death for Middle Pleistocene hominids and Neanderthals has previously been estimated at around 40–45 years in the oldest specimens. The appearance of senescence processes before this age is indicative of higher rates of morphological aging in the clade which gave rise to Neanderthals. The anatomical significance of ageing features when considered in the context of craniofacial remodelling can help in the understanding of the taxonomic status of these morphological traits.