The Aubesier 4 I2 (13) is notable for its labial bi-convexity and pronounced shoveling. The crown exhibits strongly marked marginal ridges corresponding to grade 6 shoveling of the Arizona State University Dental Anthropology System (ASUDAS) scale (16). These ridges meet lingually at an ASUDAS grade 5 tuberculum dentale. Labially, the tooth is strongly convex mesiodistally and superoinferiorly. The mesiodistal convexity is ASUDAS grade 4. This combination of strong shovel shape with a lingual tubercle and labial bi-convexity is a characteristic of Neandertal incisors and those of their Middle Pleistocene predecessors (17, 18). Although each of these characters can be found to some degree in other Homo samples, their combined presence appears to be unique to the Neandertal lineage (18). The Aubesier 4 labiolingual diameter (Table 1) is large for a later archaic Homo, being matched only by a few Neandertals and the relatively megadont Krapina sample.
The Aubesier 10 M1 or M2 crown presents little of morphological note, and its buccolingual diameter is well within the ranges of variation of later Neandertal lineage samples (Table 1). Its roots, however, exhibit marked taurodontism; the three roots are almost completely bridged and fused, such that the distances between the cervix and the clefts between the adjacent roots are 72.7%, 75.3%, and 79.2% of the maximum height of the root. Taurodontism has long been noted for many, but not all, Neandertals and their predecessors (19, 20). The degree of development of this feature in Aubesier 10 is exceptional even compared with most Neandertal lineage teeth (17, 21), but it matches the degree of taurodontism found in high frequency especially in the terminal Middle Pleistocene Krapina sample (22).
The Aubesier 11 mandible presents a suite of characteristics that align it with late Middle Pleistocene members of the Neandertal lineage. Many of these features are associated with the emergence of midfacial prognathism, or the posterior movement of the lateral facial skeleton in the context of maintained anterior positioning of the midfacial (nasal and alveolar) region (23-25). Metric comparisons of the mandible are limited by its pathological alterations (see below), but the combination of characters preserved serves as a discrete trait reflection of overall mandibular proportions. Although many of these features have been considered to be Neandertal autapomorphies (26), they occur within other hominid samples and are variably present within the Neandertal lineage; it is their higher frequency in the later Neandertal lineage, rather than their presence, which appears to be distinctive (24, 25, 27, 28).
From anterior to posterior, Aubesier 11 exhibits a strongly retreating rounded anterior mandibular symphysis, the incipient presence of a mental trigone, a modest planum alveolare, an inferior lingual torus, the mental foramen at the level of the P4/M1 interdental septum extending to the M1, the anterior marginal tubercle at P4/M1, a distinctive retromolar space in norma lateralis, the absence of lingular (horizontal-oval) mandibular foramen bridging, a prominent superior medial pterygoid tubercle, and an intersection of the mandibular notch crest with the middle third of the mandibular condyle.
Two of these features, the anterior symphyseal profile and the lingual torus, are plesiomorphous features and largely serve to distinguish Aubesier 11 from the majority of the later Neandertals. The lateral corpus, as best as can be estimated from the pathological condition of the specimen, appears to be relatively short and broad, in contrast to the higher and thinner ones of last glacial Neandertals. The absence of a lingular bridging of the mandibular foramen is an ancestral configuration (29), but it is found in approximately half of the more recent Neandertal lineage specimens (Table 2). The moderately posterior positions of the mental foramen and the anterior marginal tubercle relative to the dentition and the presence of a retromolar space align Aubesier 11 with the majority of the Neandertal lineage remains and separate it from the more anterior relative positions of these features in earlier African specimens; all three reflect midfacial prognathism (24, 26, 27). The hypertrophy of the superior medial pterygoid insertion on the posterior medial ramus, as reflected in its prominent tubercle, and the intersection of the mandibular notch crest with the middle third of the condyle also align Aubesier 11 with the Neandertal lineage, although their biological implications are less apparent. Indeed, except for a difference in retromolar space presence, Aubesier 11 is remarkably similar to the OIS 6 La Niche (Montmaurin) 1 mandible (30, 31).
These considerations therefore indicate that the Aubesier 4, 10, and 11 later Middle Pleistocene human remains are all fully compatible with, and reinforce the existence of, the emergence of a Neandertal craniofacial morphological during the second half of the Middle Pleistocene in the northwestern Old World. The I2 crown, the M1-2 root, and the mandibular lateral corpus and ramus all exhibit features that are observed in their highest frequency in the late Middle and early Late Pleistocene archaic Homo of the northwestern Old World.
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