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Objectives Carabelli is a nonmetric dental trait variably expressed as a small pit to a prominent cusp in the maxillary molars of modern humans. Investigations on the occurrence and expression rates of this trait have been conducted extensively, tracing its origin to genetic sources. However, there remains a lack of understanding about its potential role in chewing. In this study, we examine molar macrowear with the aim of reconstructing Carabelli trait occlusal dynamics occurring during chewing. Methods We have examined 96 deciduous and permanent maxillary molars of children and young adults from Yuendumu, an Australian Aboriginal population that was at an early stage of transition from a nomadic and hunter-gatherer way of life to a more settled existence. We apply a well-established method, called Occlusal Fingerprint Analysis, which is a digital approach for analyzing dental macrowear allowing the reconstruction of jaw movements required to produce wear pattern specific to each tooth. Results Carabelli trait slightly enlarges the surface functional area, especially in those molars where this feature is expressed in its cuspal form and it is closer to the occlusal plane. Moreover, the highly steep contact planes would also indicate that Carabelli wear areas contribute to increasing the shearing abilities of the occluded teeth, which are particularly important when processing fibrous and tough foods. Conclusions The macrowear analysis suggests that Carabelli trait in the Aboriginal people from Yuendumu slightly enhanced occlusion and probably played some functional role during mastication. Future biomechanical and microwear analyses could provide additional information on the mechanical adaptation of Carabelli trait in modern human dentition.

Objectives The analysis of prehistoric human dietary habits is key for understanding the effects of paleoenvironmental changes on the evolution of cultural and social human behaviors. In this study, we compare results from zooarchaeological, stable isotope and dental calculus analyses as well as lower second molar macrowear patterns to gain a broader understanding of the diet of three individuals who lived between the end of the Late Pleistocene and the Early Holocene (ca., 17–8 ky cal BP) in the Eastern Alpine region of Italy. Materials and methods We analyze individuals buried at the sites of Riparo Tagliente (Verona), Riparo Villabruna, and Mondeval de Sora (Belluno). The three burials provide a unique dataset for diachronically exploring the influence of climatic changes on human subsistence strategies. Results Isotopic results indicate that all individuals likely relied on both terrestrial and freshwater animal proteins. Even though dental calculus analysis was, in part, hindered by the amount of mineral deposit available on the teeth, tooth macrowear study suggests that the dietary habits of the individuals included plant foods. Moreover, differences in macrowear patterns of lower second molars have been documented between Neanderthals and modern humans in the present sample, due to a prevalence of Buccal wear among the former as opposed to higher values of Lingual wear in modern human teeth. Discussion Isotopic analyses have emphasized the contribution of animal proteins in the diet of the three foragers from the Eastern Alpine region. The possible intake of carbohydrate-rich plant foods, suggested by the retrieval of plant remains in dental calculus, is supported by the signal of macrowear analysis. Moreover, the latter method indicates that the distribution of macrowear in lower second molars (M2s) allows us to discriminate between Neanderthals and modern humans within the present reference sample. Overall, our results show these three prehistoric hunter-gatherers were well adapted to the environment in which they lived exploiting many natural resources.

Morphometrics of the molar crown is based traditionally on diameter measurements but is nowadays more often based on 2D image analysis of crown outlines. An alternative approach involves measurements at the level of the cervical line. We compare the information content of the two options in a three-dimensional (3D) digital sample of lower and upper first molars (M(1) and M(1) ) of modern human and Neanderthal teeth. The cervical outline for each tooth was created by digitizing the cervical line and then sectioning the tooth with a best fit plane. The crown outline was projected onto this same plane. The curves were analyzed by direct extraction of diameters, diagonals, and area and also by principal component analysis either of the residuals obtained by regressing out these measurements from the radii (shape information) or directly by the radii (size and shape information). For M(1) , the crown and cervical outline radii allow us to discriminate between Neanderthals and modern humans with 90% and 95% accuracy, respectively. Fairly good discrimination between the groups (80-82.5%) was also obtained using cervical measurements. With respect to M(1) , general overlap of the two groups was obtained by both crown and cervical measurements; however, the two taxa were differentiable by crown outline residuals (90-97%). Accordingly, while crown diameters or crown radii should be used for taxonomic analysis of unworn or slightly worn M(1) s, the crown outline, after regressing out size information, could be promising for taxonomic assignment of lower M1s.

Information about food ingestion and mastication behavior during the lifespan of an individual is encoded in the dental occlusal wear pattern. To decode this information, we describe a new method called occlusal fingerprint analysis (OFA). Structural parameters of wear facets on the occlusal surface of teeth are quantified from digitized casts for the interpretation of occlusal aspects. The OFA provides an individual three-dimensional dental occlusal compass that indicates the major pathways of interaction between antagonists, revealing information about development, spatial position, and enlargement of wear facets. Humans develop a very similar overall pattern of crown contacts, although specific characteristics of wear facets reflect an individual's occlusal relationships and masticatory behavior. We hypothesize that the wear pattern is a unique character and therefore valuable for individual identification. Furthermore we suggest that OFA, when further developed, may be useful for identification of behavioral, biological, and chemical factors affecting crown morphology.

Neanderthals have been commonly depicted as top predators who met their nutritional needs by focusing entirely on meat. This information mostly derives from faunal assemblage analyses and sta- ble isotope studies: methods that tend to underestimate plant consumption and overestimate the intake of ani- mal proteins. Several studies in fact demonstrate that there is a physiological limit to the amount of animal proteins that can be consumed: exceeding these values causes protein toxicity that can be particularly danger- ous to pregnant women and newborns. Consequently, to avoid food poisoning from meat-based diets, Neander- thals must have incorporated alternative food sources in their daily diets, including plant materials as well. Yrbk Phys Anthropol 156:43-71, 2015. V C 2014 American Association

Department of Palaeoanthropology and Messel Research, Senckenberg Research Institute, D-60325 Frankfurt amMain, GermanyKEY WORDS Neanderthals; anatomically modern humans; occlusal compass; Levant;para-facetsABSTRACT Neanderthals and anatomically modernhumans (AMHs) may have lived in close proximity inthe Near East region during Middle Paleolithic times.Although functional morphological analyses suggest amarked behavioral contrast between these two humangroups, new dental micro- and macro-wear studies,together with new archaeological data, have revealedsome similarities in ecology and dietary habits. In thisstudy, we analyze the tooth wear patterns of Neander-thals and AMH from Middle Paleolithic sites of Israeland Northern Iraq, using the Occlusal Fingerprint Anal-ysis (OFA) method to virtually reconstruct the jaw move-ments responsible for the creation of the occlusal wearareas. We particularly focus on para-facets, a distinctivetype of wear which has been previously described in thedentition of historic and modern hunter-gatherers. Theanalysis reveals a similarity in para-facet frequencybetween early Near Eastern Neanderthals and AMH,and a significant difference with other Pleistocenehuman groups. The absence of antagonist occlusal con-tacts in the lower teeth and the occlusal compass analy-sis suggest that para-facet formation is not related tonormal mastication but to nonmasticatory activities.Thus, the identification of these nonmasticatory wearareas on the molars of early Near Eastern Neanderthalsand AMH may indicate analogous tooth-tool uses fordaily task activities. These may have emerged independ-ently or could be interpreted as indirect evidence of cul-tural interactions between these two groups. Am J PhysAnthropol 152:107-117, 2013.

The determination of the minimum number of individuals can be very challenging, especially in an assemblage of fragmentary bones and isolated teeth. Similarities in tooth morphology, degree of wear, and interproximal wear facets (IPWF) are generally used to associate isolated teeth qualitatively. However, no quantitative method has yet been established for an objective identification and matching of isolated tooth crowns. In this study, we analyze the IPWF morphology of adjacent mandibular molars (17 M(1)/M(2) pairs), applying both qualitative and quantitative methods to test a reproducible approach for crown association. The surfaces of distal (for M(1)) and mesial (for M(2)) IPWF were surface-scanned and digitally selected. Three-dimensional (3D) and two-dimensional (2D) outlines of IPWF were analyzed using elliptic Fourier analysis (EFA) and geometric morphometrics methods (GMM). Additionally, teeth were qualitatively associated by visual evaluation of the IPWF outline and by physical matching. Unsatisfactory results with less than 50% of tooth pairs correctly associated were obtained by using both methods, shape analysis (digital approach) and the visual evaluation (qualitative assessment) of the IPWF outline. The physical matching of the crowns showed highly variable accuracy ranging between 53% and 77%. The quantitative form-space analysis of 2D IPWF outlines provided the best results (82% of correctly associated teeth), but no statistically significant differences were recorded when compared with the manual matching. Since three tooth pairs out of 17 could not be quantitatively associated, we suggest that the quantitative analysis of IPWF should be used only in addition with other approaches.

Neanderthals and anatomically modern humans (AMHs) may have lived in close proximity in the Near East region during Middle Paleolithic times. Although functional morphological analyses suggest a marked behavioral contrast between these two human groups, new dental micro- and macro-wear studies, together with new archaeological data, have revealed some similarities in ecology and dietary habits. In this study, we analyze the tooth wear patterns of Neanderthals and AMH from Middle Paleolithic sites of Israel and Northern Iraq, using the Occlusal Fingerprint Analysis (OFA) method to virtually reconstruct the jaw movements responsible for the creation of the occlusal wear areas. We particularly focus on para-facets, a distinctive type of wear which has been previously described in the dentition of historic and modern hunter-gatherers. The analysis reveals a similarity in para-facet frequency between early Near Eastern Neanderthals and AMH, and a significant difference with other Pleistocene human groups. The absence of antagonist occlusal contacts in the lower teeth and the occlusal compass analysis suggest that para-facet formation is not related to normal mastication but to nonmasticatory activities. Thus, the identification of these nonmasticatory wear areas on the molars of early Near Eastern Neanderthals and AMH may indicate analogous tooth-tool uses for daily task activities. These may have emerged independently or could be interpreted as indirect evidence of cultural interactions between these two groups.