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We present the Sr isotopic composition of enamel of the most ancient deciduous tooth ever discovered in Italy to assess human mobility in Middle Pleistocene. Reconstructing ancient mobility is crucial for understanding human strategy at exploiting temporally and spatially patchy resources, with most studies focusing on indirect evidences, ultimately affecting our interpretation on hominin territoriality and energetic costs invested by hominin groups. Here, we use the high spatial resolution and micro-destructivity options offered by the Laser Ablation Multi-Collector Inductively Coupled Plasma Mass Spectrometry technique, to determine the 87 Sr/ 86 Sr intra-tooth variability of a human deciduous incisor from the Middle Pleistocene layers of the Isernia La Pineta site (Italy). We compared these data with the Sr isotopic signature of local micro-mammals, the broadest home-range of the macro-mammals and with modern plant samples. Our study reveals that while macro-mammals have possibly migrated through the landscape for up to 50 km, the pregnant woman from Isernia was probably local, given that the isotopic ratio of the enamel falls within the local range and is comparable with the signature of the local plants in a radius of 10 km. This is the first case study of Sr isotopic composition determination in such ancient deciduous tooth.

The presence of Neandertals in Europe and Western Eurasia before the arrival of anatomically modern humans is well supported by archaeological and paleontological data. In contrast, fossil evidence for Denisovans, a sister group of Neandertals recently identified on the basis of DNA sequences, is limited to three specimens, all of which originate from Denisova Cave in the Altai Mountains (Siberia, Russia). We report the retrieval of DNA from a deciduous lower second molar ( Denisova 2 ), discovered in a deep stratigraphic layer in Denisova Cave, and show that this tooth comes from a female Denisovan individual. On the basis of the number of "missing substitutions" in the mitochondrial DNA determined from the specimen, we find that Denisova 2 is substantially older than two of the other Denisovans, reinforcing the view that Denisovans were likely to have been present in the vicinity of Denisova Cave over an extended time period. We show that the level of nuclear DNA sequence diversity found among Denisovans is within the lower range of that of present-day human populations.

The dispersal of the genus Homo out of Africa approximately 1.8 million years ago (Ma) has been understood within the context of changes in diet, behavior, and bipedal locomotor efficiency. While various morphological characteristics of the knee and ankle joints are considered part of a suite of traits indicative of, and functionally related to, habitual bipedal walking, the timing and phylogenetic details of these morphological changes remain unclear. To evaluate the timing of knee and ankle joint evolution, we apply geometric morphometric methods to three-dimensional digital models of the proximal and distal tibiae of fossil hominins, Holocene Homo sapiens, and extant great apes. Two sets of landmarks and curve semilandmarks were defined on each specimen. Because some fossils were incomplete, digital reconstructions were carried out independently to estimate missing landmarks and semilandmarks. Group shape variation was evaluated through shape-and form-space principal component analysis and fossil specimens were projected to assess variation in the morphological space computed from the extant comparative sample. We show that a derived proximal tibia (knee) similar to that seen in living H. sapiens evolved with early Homo at ∼2 Ma. In contrast, derived characteristics in the distal tibia appear later, probably with the arrival of Homo erectus. These results suggest a dissociation of the morphologies of the proximal and distal tibia, perhaps indicative of divergent functional demands and, consequently, selective pressures at these joints. It appears that longer distance dispersals that delivered the Dmanisi hominins to Georgia by 1.8 Ma and H. erectus to east-southeast Asia by 1.6 Ma were facilitated by the evolution of a morphologically derived knee complex comparable to that of recent humans and an ankle that was morphologically primitive. This research sets the foundation for additional paleontological, developmental, and functional research to better understand the mechanisms underlying the evolution of bipedalism., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objectives: Early evidence for the treatment of dental pathology is found primarily among food-producing societies associated with high levels of oral pathology. However, some Late Pleistocene hunter-gatherers show extensive oral pathology, suggesting that experimentation with therapeutic dental interventions may have greater antiquity. Here, we report the second earliest probable evidence for dentistry in a Late Upper Paleolithic hunter-gatherer recovered from Riparo Fredian (Tuscany, Italy)., Materials and Methods: The Fredian 5 human consists of an associated maxillary anterior dentition with antemortem exposure of both upper first incisor (I 1 ) pulp chambers. The pulp chambers present probable antemortem modifications that warrant in-depth analyses and direct dating. Scanning electron microscopy, microCT and residue analyses were used to investigate the purported modifications of external and internal surfaces of each I 1 ., Results: The direct date places Fredian 5 between 13,000 and 12,740 calendar years ago. Both pulp chambers were circumferentially enlarged prior to the death of this individual. Occlusal dentine flaking on the margin of the cavities and striations on their internal aspects suggest anthropic manipulation. Residue analyses revealed a conglomerate of bitumen, vegetal fibers, and probable hairs adherent to the internal walls of the cavities., Discussion: The results are consistent with tool-assisted manipulation to remove necrotic or infected pulp in vivo and the subsequent use of a composite, organic filling. Fredian 5 confirms the practice of dentistry-specifically, a pathology-induced intervention-among Late Pleistocene hunter-gatherers. As such, it appears that fundamental perceptions of biomedical knowledge and practice were in place long before the socioeconomic changes associated with the transition to food production in the Neolithic., (© 2017 Wiley Periodicals, Inc.)

Fossil evidence points to an African origin of Homo sapiens from a group called either H. heidelbergensis or H. rhodesiensis. However, the exact place and time of emergence of H. sapiens remain obscure because the fossil record is scarce and the chronological age of many key specimens remains uncertain. In particular, it is unclear whether the present day 'modern' morphology rapidly emerged approximately 200 thousand years ago (ka) among earlier representatives of H. sapiens or evolved gradually over the last 400 thousand years. Here we report newly discovered human fossils from Jebel Irhoud, Morocco, and interpret the affinities of the hominins from this site with other archaic and recent human groups. We identified a mosaic of features including facial, mandibular and dental morphology that aligns the Jebel Irhoud material with early or recent anatomically modern humans and more primitive neurocranial and endocranial morphology. In combination with an age of 315 ± 34 thousand years (as determined by thermoluminescence dating), this evidence makes Jebel Irhoud the oldest and richest African Middle Stone Age hominin site that documents early stages of the H. sapiens clade in which key features of modern morphology were established. Furthermore, it shows that the evolutionary processes behind the emergence of H. sapiens involved the whole African continent.

The late Middle Palaeolithic (MP) settlement patterns in the Levant included the repeated use of caves and open landscape sites. The fossil record shows that two types of hominins occupied the region during this period-Neandertals and Homo sapiens. Until recently, diagnostic fossil remains were found only at cave sites. Because the two populations in this region left similar material cultural remains, it was impossible to attribute any open-air site to either species. In this study, we present newly discovered fossil remains from intact archaeological layers of the open-air site 'Ein Qashish, in northern Israel. The hominin remains represent three individuals: EQH1, a nondiagnostic skull fragment; EQH2, an upper right third molar (RM 3 ); and EQH3, lower limb bones of a young Neandertal male. EQH2 and EQH3 constitute the first diagnostic anatomical remains of Neandertals at an open-air site in the Levant. The optically stimulated luminescence ages suggest that Neandertals repeatedly visited 'Ein Qashish between 70 and 60 ka. The discovery of Neandertals at open-air sites during the late MP reinforces the view that Neandertals were a resilient population in the Levant shortly before Upper Palaeolithic Homo sapiens populated the region.

Objectives: The aim of the study is the assessment of Nadale 1, a Neanderthal deciduous tooth recently discovered in Northeastern Italy in the De Nadale cave (Middle Palaeolithic). Together with the clear archaeological context of the site, this study brings new insight on Neanderthal behavior and dental morphological variability., Materials and Methods: We used microCT data to provide a morphological description and morphometric analysis (diameter measurements and dental tissue volumes) of the Nadale 1 human tooth. Microwear analysis, taphonomical investigation and caries identification were performed using a stereomicroscope and Scanning Electron Microscope., Results: In terms of morphology (i.e., incipient tuberculum molare, marked mesial marginal ridge and well-developed mid-trigonid crest connecting the protoconid and the metaconid, deep anterior fovea) and size, Nadale 1 presents features frequently observed in Neanderthal lower first deciduous molars. Microscope investigations reveal the presence of a small pit which could be correlated to an incipient caries., Conclusion: Nadale 1 expands the Italian Middle Palaeolithic fossil record and provides further information on Neanderthal dm1s in terms of dimensional and morphological variability. Furthermore, the presence of an incipient caries brings further data on Neanderthal diet., (© 2016 Wiley Periodicals, Inc.)

Australopiths exhibit a number of derived facial features that are thought to strengthen the face against high and/or repetitive loads associated with a diet that included mechanically challenging foods. Here, we use finite element analysis (FEA) to test hypotheses related to the purported strengthening role of the zygomatic root and "anterior pillar" in australopiths. We modified our previously constructed models of Sts 5 (Australopithecus africanus) and MH1 (A. sediba) to differ in the morphology of the zygomatic root, including changes to both the shape and positioning of the zygomatic root complex, in addition to creating variants of Sts 5 lacking anterior pillars. We found that both an expanded zygomatic root and the presence of "anterior pillars" reinforce the face against feeding loads. We also found that strain orientations are most compatible with the hypothesis that the pillar evolved to resist loads associated with premolar loading, and that this morphology has an ancillary effect of strengthening the face during all loading regimes. These results provide support for the functional hypotheses. However, we found that an anteriorly positioned zygomatic root increases strain magnitudes even in models with an inflated/reinforced root complex. These results suggest that an anteriorly placed zygomatic root complex evolved to enhance the efficiency of bite force production while facial reinforcement features, such as the anterior pillar and the expanded zygomatic root, may have been selected for in part to compensate for the weakening effect of this facial configuration. Anat Rec, 300:171-195, 2017. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Objectives: In this contribution, we present a morphological description and comparative morphometric analysis of Cavallo D, a human tooth unearthed from the Mousterian FIII sublayer of Grotta del Cavallo (Apulia, Italy)., Materials and Methods: We used microCT data to provide a detailed morphological description and morphometric analysis of the Cavallo D human tooth based on traditional diameter measurements and 3D enamel thickness. Moreover, new AMS radiocarbon dating of charcoals from layers FII was carried out., Results: Morphological features observed in Cavallo D align the tooth to Neandertals. Similarly, the large size of the tooth (e.g., BL diameter) and the relatively thinner enamel thickness are typical Neandertal traits. 14 C datings of layer FII attribute the tooth to a time range of 45,600-42,900 cal BP (at 68% level of probability)., Discussion: Up to now, the Rdi 1 Cavallo D represents the most recent Neandertal human remain in southern Italy related to a radiocarbon dated stratigraphy. Moreover, since deciduous teeth have been less investigated than the permanent ones, this contribution brings new data to increase our knowledge on the variability of the Neandertal deciduous dentition., (© 2016 Wiley Periodicals, Inc.)

Modern humans arrived in Europe ~45,000 years ago, but little is known about their genetic composition before the start of farming ~8,500 years ago. Here we analyse genome-wide data from 51 Eurasians from ~45,000-7,000 years ago. Over this time, the proportion of Neanderthal DNA decreased from 3-6% to around 2%, consistent with natural selection against Neanderthal variants in modern humans. Whereas there is no evidence of the earliest modern humans in Europe contributing to the genetic composition of present-day Europeans, all individuals between ~37,000 and ~14,000 years ago descended from a single founder population which forms part of the ancestry of present-day Europeans. An ~35,000-year-old individual from northwest Europe represents an early branch of this founder population which was then displaced across a broad region, before reappearing in southwest Europe at the height of the last Ice Age ~19,000 years ago. During the major warming period after ~14,000 years ago, a genetic component related to present-day Near Easterners became widespread in Europe. These results document how population turnover and migration have been recurring themes of European prehistory.

Background: Dental biomechanics based on finite element (FE) analysis is attracting enormous interest in dentistry, biology, anthropology and palaeontology. Nonetheless, several shortcomings in FE modeling exist, mainly due to unrealistic loading conditions. In this contribution we used kinematics information recorded in a virtual environment derived from occlusal contact detection between high resolution models of an upper and lower human first molar pair (M1 and M1, respectively) to run a non-linear dynamic FE crash colliding test., Methodology: MicroCT image data of a modern human skull were segmented to reconstruct digital models of the antagonistic right M1 and M1 and the dental supporting structures. We used the Occlusal Fingerprint Analyser software to reconstruct the individual occlusal pathway trajectory during the power stroke of the chewing cycle, which was applied in a FE simulation to guide the M1 3D-path for the crash colliding test., Results: FE analysis results showed that the stress pattern changes considerably during the power stroke, demonstrating that knowledge about chewing kinematics in conjunction with a morphologically detailed FE model is crucial for understanding tooth form and function under physiological conditions., Conclusions/significance: Results from such advanced dynamic approaches will be applicable to evaluate and avoid mechanical failure in prosthodontics/endodontic treatments, and to test material behavior for modern tooth restoration in dentistry. This approach will also allow us to improve our knowledge in chewing-related biomechanics for functional diagnosis and therapy, and it will help paleoanthropologists to illuminate dental adaptive processes and morphological modifications in human evolution.

Australopithecus sediba has been hypothesized to be a close relative of the genus Homo. Here we show that MH1, the type specimen of A. sediba, was not optimized to produce high molar bite force and appears to have been limited in its ability to consume foods that were mechanically challenging to eat. Dental microwear data have previously been interpreted as indicating that A. sediba consumed hard foods, so our findings illustrate that mechanical data are essential if one aims to reconstruct a relatively complete picture of feeding adaptations in extinct hominins. An implication of our study is that the key to understanding the origin of Homo lies in understanding how environmental changes disrupted gracile australopith niches. Resulting selection pressures led to changes in diet and dietary adaption that set the stage for the emergence of our genus.

A variety of geometric morphometric methods have recently been used to describe dental shape variation in human evolutionary studies. However, the applicability of these methods is limited when teeth are worn or are difficult to orient accurately. Here we show that elliptical best fits on outlines of dental tissues below the crown provide basic size- and orientation-free shape descriptors. Using the dm(2) and M(3) as examples, we demonstrate that these descriptors can be used for taxonomic purposes, such as distinguishing between Neanderthal and recent modern human teeth. We propose that this approach can be a useful alternative to existing methodology., (© 2015 Wiley Periodicals, Inc.)

Objectives: This study investigates the effect of allometry on the shape of lower dm2 (dm2) and lower M1 (M1) crown outlines and examines whether the trajectory and magnitude of allometric scaling are shared between Neandertals and Homo sapiens., Methods: Our sample included 164 specimens: 57 recent H. sapiens, 44 Upper Paleolithic H. sapiens, 17 early H. sapiens, and 46 Neandertals. Of these, 59 represent dm2/M1 pairs from the same individuals. Occlusal photographs were used to obtain crown shapes of dm2s and M1s. Principal components analysis (PCA) of the matrix of shape coordinates was used to explore the pattern of morphological variation across the dm2 and M1 samples. Allometry was investigated by means of the Pearson product-moment correlation coefficient. Two-block partial least squares (2B-PLS) analysis was used to explore patterns of covariation between dm2 and M1 crown outlines of matched individual pairs., Results: The PCA confirmed significant differences between Neandertal and H. sapiens dm2 and M1 shapes. Allometry accounted for a small but statistically significant proportion of the total morphological variance. The magnitude of the allometric contribution to crown shape was stronger among Neandertals than among H. sapiens. However, we could not reject the null hypothesis that the two species share the same allometric trajectory. The 2B-PLS analysis of the pooled sample of paired individuals revealed a significant correlation in crown shape between dm2 and M1. While Procrustes distances differed significantly between dm2 and M1 in Neandertals, it did not among H. sapiens groups., Conclusions: Our results confirm several of the results obtained by a similar study of upper dm2/M1 (dm(2)/M(1)), but there are differences as well. Neandertal dm2/M1 shapes are less derived than those of the dm(2)/M(1). Such differences may support previous studies, which have suggested that different developmental and/or epigenetic factors affect the upper and lower dentitions., (© 2015 Wiley Periodicals, Inc.)

Prehistoric dental treatments were extremely rare, and the few documented cases are known from the Neolithic, when the adoption of early farming culture caused an increase of carious lesions. Here we report the earliest evidence of dental caries intervention on a Late Upper Palaeolithic modern human specimen (Villabruna) from a burial in Northern Italy. Using Scanning Electron Microscopy we show the presence of striations deriving from the manipulation of a large occlusal carious cavity of the lower right third molar. The striations have a "V"-shaped transverse section and several parallel micro-scratches at their base, as typically displayed by cutmarks on teeth. Based on in vitro experimental replication and a complete functional reconstruction of the Villabruna dental arches, we confirm that the identified striations and the associated extensive enamel chipping on the mesial wall of the cavity were produced ante-mortem by pointed flint tools during scratching and levering activities. The Villabruna specimen is therefore the oldest known evidence of dental caries intervention, suggesting at least some knowledge of disease treatment well before the Neolithic. This study suggests that primitive forms of carious treatment in human evolution entail an adaptation of the well-known toothpicking for levering and scratching rather than drilling practices.

Most hominin cranial fossils are incomplete and require reconstruction prior to subsequent analyses. Missing data can be estimated by geometric morphometrics using information from complete specimens, for example, by using thin-plate splines. In this study, we estimate missing data in several virtually fragmented models of hominoid crania (Homo, Pan, Pongo) and fossil hominins (e.g., Australopithecus africanus, Homo heidelbergensis). The aim is to investigate in which way different references influence estimations of cranial shape and how this information can be employed in the reconstruction of fossils. We used a sample of 64 three-dimensional digital models of complete human, chimpanzee, and orangutan crania and a set of 758 landmarks and semilandmarks. The virtually knocked out neurocranial and facial areas that were reconstructed corresponded to those of a real case found in A.L. 444-2 (A. afarensis) cranium. Accuracy of multiple intraspecies and interspecies reconstructions was computed as the maximum square root of the mean squared difference between the original and the reconstruction (root mean square). The results show that the uncertainty in reconstructions is a function of both the geometry of the knockout area and the dissimilarity between the reference sample and the specimen(s) undergoing reconstruction. We suggest that it is possible to estimate large missing cranial areas if the shape of the reference is similar enough to the shape of the specimen reconstructed, though caution must be exercised when employing these reconstructions in subsequent analyses. We provide a potential guide for the choice of the reference by means of bending energy., (© 2015 Wiley Periodicals, Inc.)

Taurodontism (i.e. enlarged pulp chamber with concomitant apical displacement of the root bi/trifurcation) is considered a dental anomaly with relatively low incidence in contemporary societies, but it represents a typical trait frequently found in Neandertal teeth. Four hypotheses can be envisioned to explain the high frequency in Neandertals: adaptation to a specific occlusal loading regime (biomechanical advantage), adaptation to a high attrition diet, pleiotropic or genetic drift effects. In this contribution we used finite element analysis (FEA) and advanced loading concepts based on macrowear information to evaluate whether taurodontism supplies some dental biomechanical advantages. Loads were applied to the digital model of the lower right first molar (RM1 ) of the Neandertal specimen Le Moustier 1, as well as to the digital models of both a shortened and a hyper-taurodontic version of Le Moustier RM1 . Moreover, we simulated a scenario where an object is held between teeth and pulled in different directions to investigate whether taurodontism might be useful for para-masticatory activities. Our results do not show any meaningful difference among all the simulations, pointing out that taurodontism does not improve the functional biomechanics of the tooth and does not favour para-masticatory pulling activities. Therefore, taurodontism should be considered either an adaptation to a high attrition diet or most likely the result of pleiotropic or genetic drift effects. Finally, our results have important implications for modern dentistry during endodontic treatments, as we observed that filling the pulp chamber with dentine-like material increases tooth stiffness, and ultimately tensile stresses in the crown, thus favouring tooth failure., (© 2014 Anatomical Society.)

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 stable isotope studies: methods that tend to underestimate plant consumption and overestimate the intake of animal 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 dangerous to pregnant women and newborns. Consequently, to avoid food poisoning from meat-based diets, Neanderthals must have incorporated alternative food sources in their daily diets, including plant materials as well., (© 2014 American Association of Physical Anthropologists.)

In a broad range of evolutionary studies, an understanding of intraspecific variation is needed in order to contextualize and interpret the meaning of variation between species. However, mechanical analyses of primate crania using experimental or modeling methods typically encounter logistical constraints that force them to rely on data gathered from only one or a few individuals. This results in a lack of knowledge concerning the mechanical significance of intraspecific shape variation that limits our ability to infer the significance of interspecific differences. This study uses geometric morphometric methods (GM) and finite element analysis (FEA) to examine the biomechanical implications of shape variation in chimpanzee crania, thereby providing a comparative context in which to interpret shape-related mechanical variation between hominin species. Six finite element models (FEMs) of chimpanzee crania were constructed from CT scans following shape-space Principal Component Analysis (PCA) of a matrix of 709 Procrustes coordinates (digitized onto 21 specimens) to identify the individuals at the extremes of the first three principal components. The FEMs were assigned the material properties of bone and were loaded and constrained to simulate maximal bites on the P(3) and M(2) . Resulting strains indicate that intraspecific cranial variation in morphology is associated with quantitatively high levels of variation in strain magnitudes, but qualitatively little variation in the distribution of strain concentrations. Thus, interspecific comparisons should include considerations of the spatial patterning of strains rather than focus only on their magnitudes., (© 2014 Wiley Periodicals, Inc.)

The African Plio-Pleistocene hominins known as australopiths evolved derived craniodental features frequently interpreted as adaptations for feeding on either hard, or compliant/tough foods. Among australopiths, Paranthropus boisei is the most robust form, exhibiting traits traditionally hypothesized to produce high bite forces efficiently and strengthen the face against feeding stresses. However, recent mechanical analyses imply that P. boisei may not have been an efficient producer of bite force and that robust morphology in primates is not necessarily strong. Here we use an engineering method, finite element analysis, to show that the facial skeleton of P. boisei is structurally strong, exhibits a strain pattern different from that in chimpanzees (Pan troglodytes) and Australopithecus africanus, and efficiently produces high bite force. It has been suggested that P. boisei consumed a diet of compliant/tough foods like grass blades and sedge pith. However, the blunt occlusal topography of this and other species suggests that australopiths are adapted to consume hard foods, perhaps including grass and sedge seeds. A consideration of evolutionary trends in morphology relating to feeding mechanics suggests that food processing behaviors in gracile australopiths evidently were disrupted by environmental change, perhaps contributing to the eventual evolution of Homo and Paranthropus., (© 2014 Wiley Periodicals, Inc.)

Enamel thickness and dental tissue proportions have been recognized as effective taxonomic discriminators between Neanderthal and modern humans teeth. However, most of the research on this topic focused on permanent teeth, and little information is available for the deciduous dentition. Moreover, although worn teeth are more frequently found than unworn teeth, published data for worn teeth are scarce and methods for the assessment of their enamel thickness need to be developed. Here, we addressed this issue by studying the 2D average enamel thickness (AET) and 2D relative enamel thickness (RET) of Neanderthal and modern humans unworn to moderately worn upper first deciduous molars (dm(1)s) and upper second deciduous molars (dm(2)s). In particular, we used 3D μCT data to investigate the mesial section for dm(1)s and both mesial and buccal sections for dm(2)s. Our results confirmed previous findings of an Neanderthal derived condition of thin enamel, and thinner enamel in dm(1)s than dm(2)s in both Neanderthal and modern humans. We demonstrated that the Neanderthal 2D RET indices are significantly lower than those of modern humans at similar wear stages in both dm(1)s and dm(2)s (p < 0.05). The discriminant analysis showed that using 2D RET from dm(1) and dm(2) sections at different wear stages up to 93% of the individuals are correctly classified. Moreover, we showed that the dm(2) buccal sections, although non-conventionally used, might have an advantage on mesial sections since they distinguish as well as mesial sections but tend to be less worn. Therefore, the 2D analysis of enamel thickness is suggested as a means for taxonomic discrimination between modern humans and Neanderthal unworn to moderately worn upper deciduous molars., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

A significant number of Middle to Late Pleistocene sites contain primarily (and sometimes only) deciduous teeth (e.g., Grotta del Cavallo, Mezmaiskaya, Blombos). Not surprisingly, there has been a recent renewed interest in deciduous dental variation, especially in the context of distinguishing Homo neanderthalensis and Homo sapiens. Most studies of the deciduous dentition of fossil hominins have focused on standard metrical variation but morphological (non-metric and morphometric) variation also promises to shed light on long standing taxonomic questions. This study examines the taxonomic significance of the crown outline of the deciduous upper second molar through principal components analysis and linear discriminant analysis. We examine whether or not the crown shape of the upper deciduous second molar separates H. neanderthalensis from H. sapiens and explore whether it can be used to correctly assign individuals to taxa. It builds on previous studies by focusing on crown rather than cervical outline and by including a large sample of geographically diverse recent human populations. Our samples include 17 H. neanderthalensis, five early H. sapiens, and 12 Upper Paleolithic H. sapiens. In addition, we include two Homo erectus specimens in order to evaluate the polarity of crown shape differences observed between H. neanderthalensis and H. sapiens. Our results show that crown outline shape discriminates H. sapiens and H. neanderthalensis quite well, but does not do well at distinguishing H. erectus from H. sapiens. We conclude that the crown outline shape observed in H. sapiens is a primitive retention and that the skewed shape observed in H. neanderthalensis is a derived condition. Finally, we explore the phylogenetic implications of the results for the H. erectus molars., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The site of Fumane Cave (western Lessini Mountains, Italy) contains a stratigraphic sequence spanning the Middle to early Upper Paleolithic. During excavations from 1989 to 2011, four human teeth were unearthed from the Mousterian (Fumane 1, 4, 5) and Uluzzian (Fumane 6) levels of the cave. In this contribution, we provide the first morphological description and morphometric analysis of the dental remains. All of the human remains, except for Fumane 6, are deciduous teeth. Based on metric data (crown and cervical outline analysis, and lateral enamel thickness) and non-metric dental traits (e.g., mid-trigonid crest), Fumane 1 (lower left second deciduous molar) clearly belongs to a Neandertal. For Fumane 4 (upper right central deciduous incisor), the taxonomic attribution is difficult due to heavy incisal wear. Some morphological features observed in Fumane 5 (lower right lateral deciduous incisor), coupled with the large size of the tooth, support Neandertal affinity. Fumane 6, a fragment of a permanent molar, does not show any morphological features useful for taxonomic discrimination. The human teeth from Fumane Cave increase the sample of Italian fossil remains, and emphasize the need to develop new methods to extract meaningful taxonomic information from deciduous and worn teeth., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The aims of this study were to investigate the effect of allometry on the shape of dm(2) and M(1) crown outlines and to examine whether the trajectory and magnitude of scaling are shared between species. The sample included 160 recent Homo sapiens, 28 Upper Paleolithic H. sapiens, 10 early H. sapiens, and 33 H. neanderthalensis (Neandertal) individuals. Of these, 97 were dm(2) /M(1) pairs from the same individuals. A two-block partial least squares analysis of paired individuals revealed a significant correlation in crown shape between dm(2) and M(1) . A principal component analysis confirmed that Neandertal and H. sapiens dm(2) and M(1) shapes differ significantly and that this difference is primarily related to hypocone size and projection. Allometry accounted for a small but significant proportion of the total morphological variance. We found the magnitude of the allometric effect to be significantly stronger in Neandertals than in H. sapiens. Procrustes distances were significantly different between the two tooth classes in Neandertals, but not among H. sapiens groups. Nevertheless, we could not reject the null hypothesis that the two species share the same allometric trajectory. Although size clearly contributes to the unique shape of the Neandertal dm(2) and M(1) , the largest H. sapiens teeth do not exhibit the most Neandertal-like morphology. Hence, additional factors must contribute to the differences in dm(2) and M(1) crown shape between these two species. We suggest an investigation of the role of timing and rate of development on the shapes of the dm(2) and M(1) may provide further answers., (Copyright © 2014 Wiley Periodicals, Inc.)

The study of enamel thickness has received considerable attention in regard to the taxonomic, phylogenetic and dietary assessment of human and non-human primates. Recent developments based on two-dimensional (2D) and three-dimensional (3D) digital techniques have facilitated accurate analyses, preserving the original object from invasive procedures. Various digital protocols have been proposed. These include several procedures based on manual handling of the virtual models and technical shortcomings, which prevent other scholars from confidently reproducing the entire digital protocol. There is a compelling need for standard, reproducible, and well-tailored protocols for the digital analysis of 2D and 3D dental enamel thickness. In this contribution we provide essential guidelines for the digital computation of 2D and 3D enamel thickness in hominoid molars, premolars, canines and incisors. We modify previous techniques suggested for 2D analysis and we develop a new approach for 3D analysis that can also be applied to premolars and anterior teeth. For each tooth class, the cervical line should be considered as the fundamental morphological feature both to isolate the crown from the root (for 3D analysis) and to define the direction of the cross-sections (for 2D analysis)., (Copyright © 2013 Wiley Periodicals, Inc.)

It has been hypothesized that the extensively overlapping temporal and parietal bones of the squamosal sutures in Paranthropus boisei are adaptations for withstanding loads associated with feeding. Finite element analysis (FEA) was used to investigate the biomechanical effects of suture size (i.e., the area of overlap between the temporal and parietal bones) on stress, strain energy, and strain ratio in the squamosal sutures of Pan troglodytes and P. boisei (specimen OH 5) during biting. Finite element models (FEMs) of OH 5 and a P. troglodytes cranium were constructed from CT scans. These models contain sutures that approximate the actual suture sizes preserved in both crania. The FEM of Pan was then modified to create two additional FEMs with squamosal sutures that are 50% smaller and 25% larger than those in the original model. Comparisons among the models test the effect of suture size on the structural integrity of the squamosal suture as the temporal squama and parietal bone move relative to each other during simulated premolar biting. Results indicate that with increasing suture size there is a decreased risk of suture failure, and that maximum stress values in the OH 5 suture were favorable compared to values in the Pan model with the normal suture size. Strain ratios suggest that shear is an important strain regime in the squamosal suture. This study is consistent with the hypothesis that larger sutures help reduce the likelihood of suture failure under high biting loads., (Copyright © 2013 Wiley Periodicals, Inc.)

In 1986-1987, three human remains were unearthed from macro-unit II of San Bernardino Cave (Berici Hills, Veneto, Italy), a deposit containing a late Mousterian lithic assemblage. The human remains (a distal phalanx, a lower right third molar and a lower right second deciduous incisor) do not show diagnostic morphological features that could be used to determine whether they were from Homo neanderthalensis or Homo sapiens. Despite being of small size, and thus more similar to recent H. sapiens, the specimens were attributed to Neandertals, primarily because they were found in Mousterian layers. We carried out a taxonomic reassessment of the lower right third molar (LRM3; San Bernardino 4) using digital morphometric analysis of the root, ancient DNA analysis, carbon and nitrogen isotope analyses, and direct accelerator mass spectrometry (AMS) radiocarbon dating of dentine collagen. Mitochondrial DNA analysis and root morphology show that the molar belongs to a modern human and not to a Neandertal. Carbon 14 ((14)C) dating of the molar attributes it to the end of the Middle Ages (1420-1480 cal AD, 2 sigma). Carbon and nitrogen isotope analyses suggest that the individual in question had a diet similar to that of Medieval Italians. These results show that the molar, as well as the other two human remains, belong to recent H. sapiens and were introduced in the Mousterian levels post-depositionally., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

A very limiting factor for paleoanthropological studies is the poor state of preservation of the human fossil record, where fragmentation and deformation are considered normal. Although anatomical information can still be gathered from a distorted fossil, such specimens must typically be excluded from advanced morphological and morphometric analyses, thus reducing the fossil sample size and, ultimately, our knowledge of human evolution. In this contribution we provide the first digital reconstruction of the KNM-ER 1813 Homo habilis cranium. Based on state of-the-art three-dimensional digital modeling and geometric morphometric (GM) methods, the facial portion was aligned to the neurocranium, the overall distortion was removed, and the missing regions were restored. The reconstructed KNM-ER 1813 allows for an adjustment of the anthropometric measurements gathered on the original fossil. It is suitable for further quantitative studies, such as GM analyses focused on skull morphology or for finite element analysis to explore the mechanics of early Homo feeding behavior and diet., (Copyright © 2013 Wiley Periodicals, Inc.)

Objectives: This study aimed to compare the patterns of stress distribution in a lower second premolar using three conventional occlusal loadings and two more realistic loading scenarios based on occlusal contact areas., Materials and Methods: The teeth of a dried modern human skull were micro-CT scanned in maximum intercuspation contact with a Viscom X8060 NDT X-ray system. A kinematic analysis of the surface contacts between antagonistic right upper and lower teeth during the power stroke was carried out in the Occlusal Fingerprint Analyser (OFA) software. Stress distribution in the lower right second premolar was analysed using three-dimensional finite element (FE) methods, considering occlusal information taken from OFA results (cases 4-5). The output was compared to that obtained by loading the tooth with a single point force (cases 1-3)., Results: Results for cases 1-3 differ considerable from those of cases 4-5. The latter show that tensile stresses might be concentrated in grooves and fissures of the occlusal surface, in the marginal ridges, in the disto-lingual and in the distal side of the root. Moreover, the premolar experiences high tensile stresses in the buccal aspect of the crown, supporting the idea that abfraction might be a dominant factor in the aetiology of non-carious cervical lesions., Conclusions: The application of FE methods in dental biomechanics can be advanced considering individual wear patterns., Clinical Relevance: More realistic occlusal loadings are of importance for both new developments in prosthetic dentistry and improvements of materials for tooth restoration, as well to address open questions about the worldwide spread problem of dental failure.

The scarcity of Neandertal remains from Southern Europe hampers our understanding of Neandertal variability, and can bias interpretations about Neandertal geographic variation. To address this issue, it is often important to reassess human remains that, while discovered decades ago, remain relatively unknown to the scientific community. In this contribution, we provide a complete state-of-the-art comparative morphometric analysis of Leuca I, an unworn left second upper molar (LM(2) ) discovered in 1958 in Bambino's Cave (near Santa Maria di Leuca, Apulia, Italy) and attributed to Homo neanderthalensis. Our study includes comparisons of standard metric and nonmetric data, a 2D image analysis of the occlusal surface and measurements of both 2D and 3D enamel thickness and dental tissue proportions. Although Leuca I follows the Neandertal M(2) s trend in some morphometric aspects (i.e., small relative occlusal polygon area), in other cases it falls to the higher end (for 3D average enamel thickness) or even outside (for 3D-relative enamel thickness) the Neandertal M(2) variability, thus increasing the known Neandertal range of variation., (Copyright © 2013 Wiley Periodicals, Inc.)

Most of the morphological features recognized in hominin teeth, particularly the topography of the occlusal surface, are generally interpreted as an evolutionary functional adaptation for mechanical food processing. In this respect, we can also expect that the general architecture of a tooth reflects a response to withstand the high stresses produced during masticatory loadings. Here we use an engineering approach, finite element analysis (FEA), with an advanced loading concept derived from individual occlusal wear information to evaluate whether some dental traits usually found in hominin and extant great ape molars, such as the trigonid crest, the entoconid-hypoconulid crest and the protostylid have important biomechanical implications. For this purpose, FEA was applied to 3D digital models of three Gorillagorilla lower second molars (M2) differing in wear stages. Our results show that in unworn and slightly worn M2s tensile stresses concentrate in the grooves of the occlusal surface. In such condition, the trigonid and the entoconid-hypoconulid crests act to reinforce the crown locally against stresses produced along the mesiodistal groove. Similarly, the protostylid is shaped like a buttress to suffer the high tensile stresses concentrated in the deep buccal groove. These dental traits are less functional in the worn M2, because tensile stresses decrease physiologically in the crown with progressing wear due to the enlargement of antagonistic contact areas and changes in loading direction from oblique to nearly parallel direction to the dental axis. This suggests that the wear process might have a crucial influence in the evolution and structural adaptation of molars enabling to endure bite stresses and reduce tooth failure throughout the lifetime of an individual.

Recent biomechanical analyses examining the feeding adaptations of early hominins have yielded results consistent with the hypothesis that hard foods exerted a selection pressure that influenced the evolution of australopith morphology. However, this hypothesis appears inconsistent with recent reconstructions of early hominin diet based on dental microwear and stable isotopes. Thus, it is likely that either the diets of some australopiths included a high proportion of foods these taxa were poorly adapted to consume (i.e., foods that they would not have processed efficiently), or that aspects of what we thought we knew about the functional morphology of teeth must be wrong. Evaluation of these possibilities requires a recognition that analyses based on microwear, isotopes, finite element modeling, and enamel chips and cracks each test different types of hypotheses and allow different types of inferences. Microwear and isotopic analyses are best suited to reconstructing broad dietary patterns, but are limited in their ability to falsify specific hypotheses about morphological adaptation. Conversely, finite element analysis is a tool for evaluating the mechanical basis of form-function relationships, but says little about the frequency with which specific behaviors were performed or the particular types of food that were consumed. Enamel chip and crack analyses are means of both reconstructing diet and examining biomechanics. We suggest that current evidence is consistent with the hypothesis that certain derived australopith traits are adaptations for consuming hard foods, but that australopiths had generalized diets that could include high proportions of foods that were both compliant and tough., (Copyright © 2013 Wiley Periodicals, Inc.)

Despite the development of computer-based methods, cranial reconstruction of very large skull defects remains a challenge particularly if the damage affects the midsagittal region hampering the usage of mirror imaging techniques. This pilot study aims to deliver a new method that goes beyond mirror imaging, giving the possibility to reconstruct crania characterized by large missing areas, which might be useful in the fields of paleoanthropology, bioarcheology, and forensics. We test the accuracy of digital reconstructions in cases where two-thirds or more of a human cranium were missing. A three-dimensional (3D) virtual model of a human cranium was virtually damaged twice to compare two destruction-reconstruction scenarios. In the first case, a small fraction of the midsagittal region was still preserved, allowing the application of mirror imaging techniques. In the second case, the damage affected the complete midsagittal region, which demands a new approach to estimate the position of the midsagittal plane. Reconstructions were carried out using CT scans from a sample of modern humans (12 males and 13 females), to which 3D digital modeling techniques and geometric morphometric methods were applied. As expected, the second simulation showed a larger variability than the first one, which underlines the fact that the individual midsagittal plane is of course preferable in order to minimize the reconstruction error. However, in both simulations the Procrustes mean shape was an effective reference for the reconstruction of the entire cranium, producing models that showed a remarkably low error of about 3 mm, given the extent of missing data., (Copyright © 2013 Wiley Periodicals, Inc.)

Dental arch reconstructions present as much of a challenge in paleoanthropology as in orthodontics and maxillo-facial surgery. Dentists and dental technicians know that it is very difficult to find the precise physiological crown positions that will yield individually correct occlusal kinematics in living individuals, and this difficulty is compounded by damage and deformation in fossil specimens. Typically, dental arch reconstructions of fossils are not validated, although a functionally correct reconstruction is of undoubted importance for accurate morphological descriptions and comparative studies of fossil dentitions. Here we describe a new method for functional dental arch reconstruction derived from detailed wear facet mapping (Occlusal Fingerprint Analysis, OFA) and dental-technical approaches. OFA was used to restore the entire dental arches of the most complete late Miocene fossil great ape dentition, that of Rudapithecus hungaricus, from Rudabánya in Hungary. Dental stone casts of the maxillary and mandibular dentition were repositioned in a dental articulator. The correct alignment of the tooth crowns was monitored by physically and virtually testing the tooth contacts during occlusal movements. The characteristic distribution pattern of the individual macrowear facets strongly constrains the antagonistic crown relationships in the Rudabánya specimen. We propose that the method used to reconstruct the functional dental arches of R. hungaricus, derived from kinematic evidence encoded in macrowear patterns, can be used as a reliable foundation for dental and facial restorations in fossils, and for individual occlusal crown morphology and dental arch reconstructions in modern dentistry and prosthetics., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The ontogenetic development of the mental region still poses a number of unresolved questions in human growth, development and phylogeny. In our study we examine the hypotheses of DuBrul & Sicher (1954) (The Adaptive Chin. Springfield, IL: Charles) and Enlow (1990) (Facial Growth, 3rd edn. Philadelphia, PA: Saunders) to explain the presence of a prominent mental region in anatomically modern humans. In particular, we test whether the prominence of the mental region and the positioning of the teeth are both correlated with the developmental relocation of the tongue and the suprahyoid muscles inserting at the lingual side of the symphysis. Furthermore, we test whether the development of the mental region is associated with the development of the back of the vocal tract. Using geometric morphometric methods, we measured the 3D mandibular and tooth surfaces in a cross-sectional sample of 36 CT-scanned living humans, incorporating the positions of the tongue and the geniohyoid and digastric muscle insertions. The specimens' ages range from birth to the complete emergence of the deciduous dentition. We used multivariate regression and two-block partial least squares (PLS) analysis to study the covariation among the mental region, the muscle insertions, and the teeth both across and within age stages. In order to confirm our results from the 3D cross-sectional sample, and to relate them to facial growth and the position of the cervical column and the hyoid bone, we used 46 lateral radiographs of eight children from the longitudinal Denver Growth Study. The 3D analysis demonstrates that the lingual side of the lower border of the symphysis develops downwards and forwards. These shape changes are significantly correlated with the relocation of muscle insertion sites and also with the vertical reorientation of the anterior teeth prior to emergence. The 2D analysis confirms the idea that as the mental region prominence develops, the space of the laryngopharynx becomes restricted due to upper mid-face retraction and the acquisition of upright body posture. In agreement with the hypotheses of DuBrul & Sicher (1954) and Enlow (1990), our results suggest that the presence of a prominent mental region responds to the space restriction at the back of the vocal tract, and to the packaging of the tongue and suprahyoid muscles in order to preserve the functionality of the laryngopharynx during respiration, feeding and speech., (© 2012 The Authors Journal of Anatomy © 2012 Anatomical Society.)

The functional restoration of the occlusal relationship between maxillary and mandibular tooth rows is a major challenge in modern dentistry and maxillofacial surgery. Similar technical challenges are present in paleoanthropology when considering fragmented and deformed mandibular and maxillary fossils. Sts 52, an Australopithecus africanus specimen from Sterkfontein Member 4, represents a typical case where the original shape of the dental arches is no longer preserved. It includes a partial lower face (Sts 52a) and a fragmented mandible (Sts 52b), both incomplete and damaged to such an extent to thwart attempts at matching upper and lower dentitions. We show how the preserved macro wear pattern of the tooth crowns can be used to functionally reconstruct Sts 52's dental arches. High-resolution dental stone casts of Sts 52 maxillary and mandibular dentition were mounted and repositioned in a dental articulator. The occlusal relationship between antagonists was restored based on the analysis of the occlusal wear pattern of each preserved tooth, considering all dental contact movements represented in the occlusal compass. The reconstructed dental arches were three-dimensional surface scanned and their occlusal kinematics tested in a simulation. The outcome of this contribution is the first functional restoration of A. africanus dental arches providing new morphometric data for specimen Sts 52. It is noteworthy that the method described in this case study might be applied to several other fossil specimens., (Copyright © 2013 Wiley Periodicals, Inc.)

Despite the general increase in digital techniques for dental morphometric analyses, only a few methods are available to study worn teeth. Moreover, permanent dentitions are studied much more frequently than deciduous teeth. In this study, we address both issues by providing a taxonomic classification of Neanderthal and modern human (MH) lower second deciduous molars (dm(2) s) through the analysis of crown and cervical outlines. Crown and cervical outlines were obtained from a three-dimensional (3D) digital sample of uniformly oriented dm(2) s. Both outlines were centered on the centroid of their area and represented by 16 pseudolandmarks obtained by equiangularly spaced radial vectors out of the centroid. We removed size information from the oriented and centered outlines with a uniform scaling of the pseudolandmark configurations to unit Centroid Size. Group shape variation was evaluated separately for the dm(2) crown and cervical outlines through a shape-space principal component (PC) analysis. Finally, quadratic discriminant analysis of a subset of PCs was used to classify the specimens. Our results demonstrate that both outlines successfully separate the two groups. Neanderthals showed a buccodistal expansion and convex lingual outline shape, whilst MHs have buccodistal reduction and straight lingual outline shape. Therefore, we confirmed that the cervical outline represents an effective parameter for distinguishing between the two taxa when dealing with worn or damaged dm(2) s., (Copyright © 2012 Wiley Periodicals, Inc.)

The position of dental wear facets depends on crown morphology, antagonistic relation, and occlusal movements. The correspondence between specific directions of movements and the position of wear facets cannot be easily evaluated in vivo and has never been tested experimentally. An experimental analysis was carried out to provide evidence that explicit occlusal movements are responsible for the spatial position of wears facets. Unworn dental stone replicas of modern human prosthetic molar were mounted in a physical dental articulator, and the upper dental arch was ground against the lowers to create a wear facet pattern. The relief guided movements were constrained sequentially by means of three different condyle box setups: (1) experienced-based mean values for sagittal condyle inclination, lateroretrusion, Benett angle, and transversal condyle inclination were used; (2) pure retrusion and immediate side shift movements were added; (3) retrusion and immediate side shift were increased. Finally, the upper and lower first molars were surface scanned and macrowear facets were quantified in four wear stages. The results show that a wear facet pattern was created similar to what is seen on human molars in vivo occlusion. Some facets only developed if specific directions of movement were carried out. Therefore, we posit that an analysis of wear facet patterns is useful in recreating the individual occlusal movements. This information can be used not only to guide reproducible functional reconstructions of crown relief and dental arches but also to deduce jaw movements when, for example, isolated primate teeth are discovered in paleontological contexts., (Copyright © 2012 Wiley Periodicals, Inc.)

The important question of whether the Australopithecus africanus hypodigm is taxonomically heterogeneous revolves largely around the interpretation of the morphological variation exhibited by the fossils from Sterkfontein. The sex assignment of these specimens is a critical component in the evaluation of their morphological variability. The Sts 5 cranium is pivotal in this regard because it is the most complete and undistorted specimen attributed to A. africanus. Although it has traditionally been regarded as an adult female, this view has been challenged. In particular, it has been argued recently that Sts 5 is a juvenile and that this, together with alveolar bone loss that has supposedly reduced the size of the canine socket, has led to its misinterpretation as a female. Virtual reconstruction of the M(3) roots (and/or alveoli) contradicts arguments that these teeth were erupting at the time of death. Regardless, canine emergence and root completion are well ahead of M(3) development in juvenile australopiths from Sterkfontein. Thus, even if the M(3) root of Sts 5 was incomplete, its canine root would have been fully formed. Measurements of palate depth indicate that the alveolar margins of Sts 5 have not suffered from much (if any) bone loss in the region of the C/P(3); any additional bone would result in a palate of truly exceptional depth. Therefore, the dimensions of the canine alveolus of Sts 5 can be regarded as proxies for those of the canine root. The canine root of Sts 5 is among the smallest recorded for any Sterkfontein australopith, which provides strong support for Robert Broom's initial attribution of sex to this specimen. There is no evidence to contradict the assertion that 'Mrs. Ples' is an adult female., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Finite element analysis (FEA) is a widespread technique to evaluate the stress/strain distributions in teeth or dental supporting tissues. However, in most studies occlusal forces are usually simplified using a single vector (i.e., point load) either parallel to the long tooth axis or oblique to this axis. In this pilot study we show how lower first molar occlusal information can be used to investigate the stress distribution with 3D FEA in the supporting bone structure. The LM(1) and the LP(2) -LM(1) of a dried modern human skull were scanned by μCT in maximum intercuspation contact. A kinematic analysis of the surface contacts between LM(1) and LP(2) -LM(1) during the power stroke was carried out in the occlusal fingerprint analyzer (OFA) software to visualize contact areas during maximum intercuspation contact. This information was used for setting the occlusal molar loading to evaluate the stress distribution in the supporting bone structure using FEA. The output was compared to that obtained when a point force parallel to the long axis of the tooth was loaded in the occlusal basin. For the point load case, our results indicate that the buccal and lingual cortical plates do not experience notable stresses. However, when the occlusal contact areas are considered, the disto-lingual superior third of the mandible experiences high tensile stresses, while the medio-lingual cortical bone is subjected to high compressive stresses. Developing a more realistic loading scenario leads to better models to understand the relationship between masticatory function and mandibular shape and structures. Am J Phys Anthropol, 2012. © 2011 Wiley Periodicals, Inc., (Copyright © 2011 Wiley Periodicals, Inc.)

The discovery of new human fossil remains is one of the most obvious ways to improve our understanding of the dynamics of human evolution. The reanalysis of existing fossils using newer methods is also crucial, and may lead to a reconsideration of the biological and taxonomical status of some specimens, and improve our understanding of highly debated periods in human prehistory. This is particularly true for those remains that have previously been studied using traditional approaches, with only morphological descriptions and standard calliper measurements available. My own interest in the Uluzzian, and its associated human remains grew from my interest in applying recently developed analytical techniques to quantify morphological variation. Discovered more than 40 years ago, the two deciduous molars from Grotta del Cavallo (Apulia, Italy) are the only human remains associated with the Uluzzian culture (one of the main three European "transitional" cultures). These teeth were previously attributed to Neanderthals. This attribution contributed to a consensus view that the Uluzzian, with its associated ornament and tool complexes, was produced by Neanderthals. A reassessment of these deciduous teeth by means of digital morphometric analysis revealed that these remains belong to anatomically modern humans (AMHs). This finding contradicts previous assumptions and suggests that modern humans, and not Neanderthals, created the Uluzzian culture. Of equal importance, new chronometric analyses date these dental remains to 43,000-45,000 cal BP. Thus, the teeth from Grotta del Cavallo represent the oldest European AMH currently known.

The appearance of anatomically modern humans in Europe and the nature of the transition from the Middle to Upper Palaeolithic are matters of intense debate. Most researchers accept that before the arrival of anatomically modern humans, Neanderthals had adopted several 'transitional' technocomplexes. Two of these, the Uluzzian of southern Europe and the Châtelperronian of western Europe, are key to current interpretations regarding the timing of arrival of anatomically modern humans in the region and their potential interaction with Neanderthal populations. They are also central to current debates regarding the cognitive abilities of Neanderthals and the reasons behind their extinction. However, the actual fossil evidence associated with these assemblages is scant and fragmentary, and recent work has questioned the attribution of the Châtelperronian to Neanderthals on the basis of taphonomic mixing and lithic analysis. Here we reanalyse the deciduous molars from the Grotta del Cavallo (southern Italy), associated with the Uluzzian and originally classified as Neanderthal. Using two independent morphometric methods based on microtomographic data, we show that the Cavallo specimens can be attributed to anatomically modern humans. The secure context of the teeth provides crucial evidence that the makers of the Uluzzian technocomplex were therefore not Neanderthals. In addition, new chronometric data for the Uluzzian layers of Grotta del Cavallo obtained from associated shell beads and included within a Bayesian age model show that the teeth must date to ~45,000-43,000 calendar years before present. The Cavallo human remains are therefore the oldest known European anatomically modern humans, confirming a rapid dispersal of modern humans across the continent before the Aurignacian and the disappearance of Neanderthals., (©2011 Macmillan Publishers Limited. All rights reserved)

The Middle Paleolithic fossil human teeth from Taddeo cave in southwestern Italy were discovered in 1967, but to date only scanty and partially incorrect information has been published about them. The teeth were recovered in a reddish sandy layer from the cave's floor, which is attributed either to an early phase of Würm I (OIS 5c or 5d) or a transition phase between Würm I and Würm II (OIS 5a). In this paper, we present a revised morphological description and morphometric comparisons of the four dental remains discovered. Apart from a classic morphometric comparison, we also provide a qualitative and quantitative assessment of the internal morphology with the aid of micro-CT imaging. In addition, virtual restoration and matching of adjacent teeth were performed with 3D digital modeling and Computer-Aided Design techniques. Occlusal Fingerprint Analysis was also employed to help correctly identify each tooth. While in the previous studies, Taddeo 1 was considered either an upper right canine or a lower right canine, in the present work it has been definitely identified as lower left canine. Taddeo 2 has been reclassified as a right P(4) instead of a right P(3). Based on the occlusal and interproximal wear, we have also shown that Taddeo 2 and Taddeo 3 (right M(1)) belong to the same individual. All of the teeth show characteristic Neanderthal features in crown morphology and fissure pattern. However, although Taddeo 4 shows morphological features typical of Neanderthal M(1)s, some morphometric results (large enamel thickness, low dentine volume) recall more modern humans than Neanderthals. This result might suggest that, at least for lower first molars, the Neanderthal range of variation is large and still not clearly understood., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Simulations based on finite element analysis (FEA) have attracted increasing interest in dentistry and dental anthropology for evaluating the stress and strain distribution in teeth under occlusal loading conditions. Nonetheless, FEA is usually applied without considering changes in contacts between antagonistic teeth during the occlusal power stroke. In this contribution we show how occlusal information can be used to investigate the stress distribution with 3D FEA in lower first molars (M(1)). The antagonistic crowns M(1) and P(2)-M(1) of two dried modern human skulls were scanned by μCT in maximum intercuspation (centric occlusion) contact. A virtual analysis of the occlusal power stroke between M(1) and P(2)-M(1) was carried out in the Occlusal Fingerprint Analyser (OFA) software, and the occlusal trajectory path was recorded, while contact areas per time-step were visualized and quantified. Stress distribution of the M(1) in selected occlusal stages were analyzed in strand7, considering occlusal information taken from OFA results for individual loading direction and loading area. Our FEA results show that the stress pattern changes considerably during the power stroke, suggesting that wear facets have a crucial influence on the distribution of stress on the whole tooth. Grooves and fissures on the occlusal surface are seen as critical locations, as tensile stresses are concentrated at these features. Properly accounting for the power stroke kinematics of occluding teeth results in quite different results (less tensile stresses in the crown) than usual loading scenarios based on parallel forces to the long axis of the tooth. This leads to the conclusion that functional studies considering kinematics of teeth are important to understand biomechanics and interpret morphological adaptation of teeth., (© 2011 The Authors. Journal of Anatomy © 2011 Anatomical Society of Great Britain and Ireland.)

Traditional morphometric approaches for taxonomic assignment of Neanderthal and modern human dental remains are mainly characterized by caliper measurements of tooth crowns. Several studies have recently described differences in dental tissue proportions and enamel thickness between Neanderthal and modern human teeth. At least for the lower second deciduous molar (dm(2)), a three-dimensional lateral relative enamel thickness index has been proposed for separating the two taxa. This index has the advantage over other measurements of being applicable to worn teeth because it ignores the occlusal aspect of the crown. Nevertheless, a comparative evaluation of traditional crown dimensions and lateral dental tissue proportion measurements for taxonomic assignment of Neanderthal and modern human dm(2)s has not yet been performed. In this study, we compare various parameters gathered from the lateral aspects of the crown. These parameters include crown diameters, height of the lateral wall of the crown (lateral crown height = LCH), lateral enamel thickness, and dentine volume of the lateral wall, including the volume of the coronal pulp chamber (lateral dentine plus pulp volume = LDPV), in a 3D digital sample of Neanderthal and modern human dm(2)s to evaluate their utility in separating the two taxa. The LDPV and the LCH allow us to discriminate between Neanderthals and modern humans with 88.5% and 92.3% accuracy, respectively. Though our results confirm that Neanderthal dm(2)s have lower relative enamel thickness (RET) index compared with modern humans (p = 0.005), only 70% of the specimens were correctly classified on the basis of the RET index. We also emphasize that results of the lateral enamel thickness method depend on the magnitude of the interproximal wear. Accordingly, we suggest using the LCH or the LDPV to discriminate between Neanderthal and modern human dm(2)s. These parameters are more independent of interproximal wear and loss of lateral enamel., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The OH5 cranium, holotype of Paranthropus boisei consists of two main portions that do not fit together: the extensively reconstructed face and a portion of the neurocranium. A physical reconstruction of the cranium was carried out by Tobias in 1967, who did not discuss problems related to deformation, although he noted a slight functional asymmetry. Nevertheless, the reconstructed cranium shows some anomalies, mainly due to the right skewed position of the upper calvariofacial fragment and uncertainty of the relative position of the neurocranium to the face, which hamper further quantitative analysis of OH5's cranial geometry. Here, we present a complete virtual reconstruction of OH5, using three-dimensional (3D) digital data, geometric morphometric (GM) methods and computer-aided design (CAD) techniques. Starting from a CT scan of Tobias's reconstruction, a semi-automatic segmentation method was used to remove Tobias's plaster. The upper calvariofacial fragment was separated from the lower facial fragment and re-aligned using superposition of their independent midsagittal planes in a range of feasible positions. The missing parts of the right hemiface were reconstructed using non-uniform rational basis-spline (NURBS) surface and subsequently mirrored using the midsagittal plane to arrive at a symmetrical facial reconstruction. A symmetric neurocranium was obtained as the average of the original shape and its mirrored version. The alignment between the two symmetric shapes (face and neurocranium) used their independent midsagittal plane and a reference shape (KNM-ER 406) to highly reduce their degrees of freedom. From the series of alternative reconstructions, we selected the middle of this rather small feasible range. When reconstructed as a range in this way, the whole cranial form of this unique specimen can be further quantified by comparative coordinate-based methods such as GM or can be used for finite element modeling (FEM) explorations of hypotheses about the mechanics of early hominin feeding and diets., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Reconstruction of fractured, distorted, or missing parts in human skeleton presents an equal challenge in the fields of paleoanthropology, bioarcheology, forensics, and medicine. This is particularly important within the disciplines such as orthodontics and surgery, when dealing with mandibular defects due to tumors, developmental abnormalities, or trauma. In such cases, proper restorations of both form (for esthetic purposes) and function (restoration of articulation, occlusion, and mastication) are required. Several digital approaches based on three-dimensional (3D) digital modeling, computer-aided design (CAD)/computer-aided manufacturing techniques, and more recently geometric morphometric methods have been used to solve this problem. Nevertheless, comparisons among their outcomes are rarely provided. In this contribution, three methods for hemimandibular body reconstruction have been tested. Two bone defects were virtually simulated in a 3D digital model of a human hemimandible. Accordingly, 3D digital scaffolds were obtained using the mirror copy of the unaffected hemimandible (Method 1), the thin plate spline (TPS) interpolation (Method 2), and the combination between TPS and CAD techniques (Method 3). The mirror copy of the unaffected hemimandible does not provide a suitable solution for bone restoration. The combination between TPS interpolation and CAD techniques (Method 3) produces an almost perfect-fitting 3D digital model that can be used for biocompatible custom-made scaffolds generated by rapid prototyping technologies., (Copyright © 2011 Wiley-Liss, Inc.)