Modern Human Teeth Research Articles

IUP Technological Signatures or Mousterian Variability? The Case of Riparo l'Oscurusciuto (Southern Italy)

In the Italian peninsula, the Late Middle Paleolithic exhibits significant technological diversity, featuring blades, points, and bladelets. Assemblages displaying these distinctive characteristics have, in some cases, been labeled as Musteriano evoluto or Evolved Mousterian, and they are interpreted as contributing to the technological and typological variability within the Middle Paleolithic. In this study, we report the results of a detailed technological analysis of the lithics recovered from the latest layers preserved at Riparo l’Oscurusciuto (SU1 to SU3) in southern Italy. These layers were previously attributed to the Late Mousterian based on their chronological age and a preliminary techno/typological analysis of a small number of artifacts. Our comprehensive analysis of entire assemblages reveals the presence of original technological features, including blades, bladelets, and specific production of micro-points on flake cores. Some of these technological traits are comparable to those recently described at Grotte Mandrin in south-eastern France, which have been attributed to an early phase of the Initial Upper Paleolithic and associated with one modern human tooth. The study confirms the variability of the Late Middle Paleolithic in southern Italy and emphasizes the necessity to reassess it considering recent theories on the earlier arrival of Homo sapiens in Europe and their potential interaction with local populations.

The Distribution and Biogenic Origins of Zinc in the Mineralised Tooth Tissues of Modern and Fossil Hominoids: Implications for Life History, Diet and Taphonomy.

Zinc is incorporated into enamel, dentine and cementum during tooth growth. This work aimed to distinguish between the processes underlying Zn incorporation and Zn distribution. These include different mineralisation processes, the physiological events around birth, Zn ingestion with diet, exposure to the oral environment during life and diagenetic changes to fossil teeth post-mortem. Synchrotron X-ray Fluorescence (SXRF) was used to map zinc distribution across longitudinal polished ground sections of both deciduous and permanent modern human, great ape and fossil hominoid teeth. Higher resolution fluorescence intensity maps were used to image Zn in surface enamel, secondary dentine and cementum, and at the neonatal line (NNL) and enamel-dentine-junction (EDJ) in deciduous teeth. Secondary dentine was consistently Zn-rich, but the highest concentrations of Zn (range 197-1743 ppm) were found in cuspal, mid-lateral and cervical surface enamel and were similar in unerupted teeth never exposed to the oral environment. Zinc was identified at the NNL and EDJ in both modern and fossil deciduous teeth. In fossil specimens, diagenetic changes were identified in various trace element distributions but only demineralisation appeared to markedly alter Zn distribution. Zinc appears to be tenacious and stable in fossil tooth tissues, especially in enamel, over millions of years.

Magnesium isotopic composition of modern human teeth enamel and its implications for dietary reconstructions

Metal stable isotopic composition of dental enamel is a novel proxy for reconstructing human dietary structure. Magnesium is the second most prevalent element in teeth only after calcium. Significant isotopic fractionation of Mg isotopes during biological processes implies its great advantages in reconstructing human recipes. To evaluate the potential of the Mg isotopic composition of dental enamel in learning the human dietary structure, elemental and Mg isotopic analyses were performed on the modern human teeth from regions in northern and southern China with various dietary characteristics. Our findings reveal that southern Chinese teeth enamel has higher Mg contents and heavier Mg isotopic compositions (-0.69‰ for SN and -0.66‰ for Hangzhou) than those of their northern counterparts (−1.27‰ for Weinan and −1.33‰ for Puyang). Such discrepancy cannot be attributed to the provenance heterogeneity or individual metabolic processes. Instead, the correlations between cereal-based dietary patterns and the δ26Mg in dental enamel demonstrate that the structure of the staple diet is more responsible for the Mg isotopic signatures. Moreover, heavier Mg isotopic compositions have been observed in dental enamel of individuals with higher rice and lower wheat in the diet, indicating that Mg isotopes are a promising tracer for rebuilding individual or population plant-based dietary structures as well as distinguishing more specific species within C3 plants. These findings suggest that Mg isotopes in teeth enamel have the great potential to better identify the food composition and constrain the diet structure of ancient humans.

Foundation and Frontier – Centenary Path of Dental Anthropology in China

Dental anthropology has been developed for 100 years in China. In this paper, the author reviews the articles on dental anthropology related to Chinese materials in the past one hundred years and briefly introduces the issues involved such as human evolution, and the interaction of different populations in historical periods. Results and discussion. The work of foreign scholars has been the foundation of Chinese paleoanthropology and dental anthropology since the discovery of the Hetao human teeth and the Zhoukoudian site. Since then, dental anthropology in China has gone through a phase of material accumulation, a phase of introducing the American ASUDAS in the 1990s, and a phase of prosperity in the last 30 years. The numerous discoveries and the application of new techniques have brought Chinese dental anthropology to an international level. Until now, there are more than 70 human fossil sites in China, over 60 of which contain human dental remains. Less material has been found from the early Pleistocene, and there is some controversy on whether they belong to the genus Homo. While early Middle Pleistocene Homo erectus teeth show primitiveness and some special features, the late Middle Pleistocene human teeth show greater variability, and mosaic features, and there is some controversy on whether some fossils belong to early Homo sapiens or other taxa. The Late Pleistocene human dentition is related to the question of how and when early modern human appeared in China and the evolution of early modern humans. However, due to the incompleteness of the material, the question of human origins is a matter of multidisciplinary and comprehensive interpretation. About 10 sites were studied from Neolithic to modern human dentition using the American ASUDAS. These results show the consistency of non-metric traits in teeth and skulls, display differences between northern and southern Chinese populations, and reveal the exchange between northwestern Chinese and western populations. Some of these results have been confirmed by paleogenomics. Conclusion. Anthropologists began to pay more attention to the morphology of modern human teeth. In the future, the application of new methods and the collection of modern human materials will help us better understand the evolution of ancient humans, population interaction.

Modern human teeth unearthed from below the ∼128,000-year-old level at Punung, Java: A case highlighting the problem of recent intrusion in cave sediments

The emergence of modern humans in the eastern edge of the Eurasian Continent is debated between two major models: early (∼130−70 ka) and late (∼50 ka) dispersal models. The former view is grounded mainly on the claims that several cave sites in Southeast Asia and southern China yielded modern human fossils of those early ages, but such reports have been disputed for the lack of direct dating of the human remains and insufficient documentation of stratigraphy and taphonomy. By tracing possible burial process and conducting direct dating for an early Late Pleistocene paleontological site of Punung III, East Java, we here report a case that demonstrates how unexpected intrusion of recent human remains into older stratigraphic levels could occur in cave sediments. This further highlights the need of direct dating and taphonomic assessment before accepting either model. We also emphasize that the state of fossilization of bones and teeth is a useful guide for initial screening of recent intrusion and should be reported particularly when direct dating is unavailable. Additionally, we provide a revised stratigraphy and faunal list of Punung III, a key site that defines the tropical rainforest Punung Fauna during the early Late Pleistocene of the region.

A novel system for classifying tooth root phenotypes.

Human root and canal number and morphology are highly variable, and internal root canal form and count does not necessarily co-vary directly with external morphology. While several typologies and classifications have been developed to address individual components of teeth, there is a need for a comprehensive system, that captures internal and external root features across all teeth. Using CT scans, the external and internal root morphologies of a global sample of humans are analysed (n = 945). From this analysis a method of classification that captures external and internal root morphology in a way that is intuitive, reproducible, and defines the human phenotypic set is developed. Results provide a robust definition of modern human tooth root phenotypic diversity. The method is modular in nature, allowing for incorporation of past and future classification systems. Additionally, it provides a basis for analysing hominin root morphology in evolutionary, ecological, genetic, and developmental contexts.

Strontium isotope evidence for Neanderthal and modern human mobility at the upper and middle palaeolithic site of Fumane Cave (Italy)

To investigate the mobility patterns of Neanderthals and modern humans in Europe during the Middle-to-Upper Palaeolithic transition period, we applied strontium isotope analysis to Neanderthal (n = 3) and modern human (n = 2) teeth recovered from the site of Fumane Cave in the Monti Lessini region of Northern Italy. We also measured a large number of environmental samples from the region, to establish a strontium ‘baseline’, and also micromammals (vole teeth) from the levels associated with the hominin teeth. We found that the modern humans and Neanderthals had similar strontium isotope values, and these values match the local baseline values we obtained for the site and the surrounding region. We conclude that both groups were utilizing the local mountainous region where Fumane Cave is situated, and likely the nearby Lessini highlands and Adige plains, and therefore the strontium evidence does not show differening mobility patterns between Neanderthals and modern humans at the Fumane site.

Comparative study of B content and δ11 B in the enamel of isolated teeth from brothers in the same family.

The quantity of boron (B) and its isotopic ratios in tooth can provide information on dietary habits and oral health of individuals. These metrics are gradually being used in stomatology, environmental science and geochemistry. This study measured the B concentration and δ11 B in the enamel of isolated teeth from brothers in the same family living in high-B-exposure areas at different times using inductively coupled plasma mass spectrometry (ICP-MS) and multicollector ICP-MS. The results demonstrate that B content in tooth samples of two brothers is related to the time of shedding. The earlier the time of shedding, the lower is the B content in tooth. The B content increased from 20.5μg/g of the central incisor (6-7years old) of the younger brother to 50.4μg/g of the second molar (10-12 years old). And B content for the elder brother increased from 28.7 to 58.3μg/g at the same positions. In the same family, the diet and environmental input of B is basically similar, and the B exposure is basically the same every year. The annual growth rate of B for the younger brother in this experiment is about 4.98 μg/g per year and that for the elder brother is about 4.93 μg/g per year. The δ11 B of shed teeth at different times from the same person is basically similar, but different from person to person. The δ11 B of shed teeth from the elder brother varies from 15.5‰ to 17.9‰ and from the younger brother varies from 5.2‰ to 6.7‰. The δ11 B is quite different for the brothers in the same family who had the same food and environmental intake of B. The experimental data confirmed the relationship between the information of B (B content and δ11 B) in shed teeth and B exposure. They provided an experimental basis using modern human teeth to apply B-isotope paleo-environmental significance.

New discovery of Late Pleistocene modern human teeth from Chongzuo, Guangxi, southern China

An increasing number of multidisciplinary field and laboratory projects focused on paleoanthropological sites from different areas of Asia are resulting in the discovery of many important findings. One such key area is southern China, particularly in the karst limestone caves of Guangxi Zhuang Autonomous Region, as a number of important hominin fossils have been discovered in recent years. In order to more intensively investigate the vast karst deposits of southern Guangxi, beginning in 2016 we initiated a systematic survey and excavation research program in Chongzuo City, southwest Guangxi. To date, this new field research initiative resulted in the discovery of eight new vertebrate fossil localities. One of these sites is the Yanlidong (“YLD”) cave, which in addition to yielding a rich collection of vertebrate fossils, also included the discovery of three hominin fossil teeth. Based on morphological and metric comparisons, we tentatively assigned these three teeth to modern Homo sapiens. Optically stimulated luminescence (OSL) dating of fossiliferous sediment indicate that age of these human teeth can be constrained between 30 and 65 ka. The implications of this new evidence from YLD and other nearby caves for the origin of modern humans in eastern Asia debate are discussed.

Enamel mineralization and compositional time-resolution in human teeth evaluated via histologically-defined LA-ICPMS profiles

Abstract Mammalian dental enamel is a key archive for the reconstruction of past environments. Sequentially mineralizing enamel provides continuous, several year-long records, which spatially-resolved sampling can ‘read’ at seasonal or higher time resolution. Yet it remains underexplored how much an initially incorporated compositional signal is overprinted by the two-stage enamel mineralization process, which affects the finally achievable time-resolution. We report results of a systematic investigation into histologically-defined compositional profiles from human enamel obtained by laser-ablation inductively-coupled-plasma mass spectrometry (LA-ICPMS). Sr/Ca, Zn/Ca, Ba/Ca and Pb/Ca are investigated as commonly-utilized proxies of (palaeo)diet, mineralization and/or pollution in modern and archaeological samples. Our modern human teeth are from unequivocally breast-fed and formula-fed individuals, respectively. By focusing on two profiles that are time-equivalent yet topographically different, namely the enamel-dentine junction (EDJ) vs. enamel prisms (P), we evaluate the compositional effect of enamel secretion vs. maturation on elemental proxies throughout enamel thickness. These two broadly orthogonal orientations are compared with the connecting Neonatal/Retzius (NNL/R) profiles that represent nominal isogrowth events during enamel secretion, which – if later maturation had no effect – should show invariant compositional signals across enamel. However, we find that all NNL/R profiles record systematically varying compositions across enamel, with Sr/Ca always decreasing by 30–80% and Zn/Ca increasing near-exponentially 20–35 times towards outer enamel. As such they can be used to benchmark the extent of enamel maturation. Since all prism profiles reveal signals similar to NNL/R for Sr, Zn and in part Ba, this unequivocally demonstrates that P-orientations are equally overprinted by maturation, in all cases with increasing intensity towards outer enamel. EDJ and P profiles do not match one-another despite representing coeval secretion time, and we infer that the highest degree of initial signal variability can be retrieved along the EDJ (approx. ≤ 100 μm) where maturation had the least effect. Using a simple two-component mixing model we show that during maturation only a moderate increase (1.3–1.9×) in discrimination against Sr is required to explain the Sr/Ca patterns. The Zn/Ca increase on the other hand is interpreted to reflect the Zn-binding motifs of the enzymes MMP-20 (matrix metalloproteinase-20) and KLK-4 (kallikrein-4) active during enamel secretion and maturation, which may preferentially imprint a Zn compositional signal in maturing enamel. In the case of Ba/Ca we find no systematic patterns analogous to that of Sr and Zn in modern samples. Moreover, cryptic diagenesis affecting Ba in otherwise well-preserved fossil teeth argues for caution when using Ba/Ca to infer nutritional signals without additional elemental/isotopic corroboration. Unlike all other investigated elements, Pb/Ca shows broadly similar EDJ-P profiles, and nearly invariant R-signals across enamel, which may reflect the affinity of Pb to both organic molecules and inorganic apatite during enamel mineralization. Overall our results reveal the element-specific behaviour of Sr, Zn, Ba and Pb during enamel mineralization.

Root growth and dental eruption in modern human deciduous teeth with preliminary observations on great apes

Recent studies of dental development have indicated that root growth rates are linked to the eruption of some permanent tooth types in modern humans and Pan troglodytes. Little is known about the potential links between these aspects of dental development in deciduous teeth of any primate species. This histology study calculates the rate at which roots extend in length for human deciduous maxillary teeth and a small sample of deciduous canines and premolars from P. troglodytes and Pongo pygmaeus. Links are sought between root extension rates and previously published data for deciduous tooth emergence in each of these species. Results reported here provide the first evidence that the roots of human deciduous incisors, canines, and premolars extend in length at an accelerated rate as these teeth emerge. Accelerated extension rates in a deciduous canine from Pan coincided with the age that this tooth type emerged in captive chimpanzees. High extension rates in a canine from Pongo preceded emergence age. Preliminary observations indicate that deciduous canine and premolar roots of Pan and Pongo extend in length rapidly when compared to these tooth types from modern human children. This study provides a starting point from which to investigate new links between the incremental development of deciduous roots and tooth emergence in primates.

The Middle-Upper Paleolithic transition in Northwest Italy: new evidence from Riparo Bombrini (Balzi Rossi, Liguria, Italy)

We report here preliminary results from four seasons of excavation at the rockshelter of Riparo Bombrini (2002–2005). Three markedly separate horizons were uncovered: the deepest, comprising Levels M1-7, yielded abundant Mousterian lithics and faunal remains. A second macro-unit, corresponding to Levels MS1-2, is only a few decimeters thick and is characterized by the presence of large limestone blocks from partial collapse of the shelter's vault. The scarcity of material and presence of carnivore coprolites suggest sporadic human occupation. The third macro-unit, constituted by Levels A1-3 and following immediately above Levels MS1-2, contains a rich Proto-Aurignacian industry, including Dufour bladelets, bone tools, abundant ochre, numerous decorative objects (mainly perforated shells) and widespread use of exotic raw material. New AMS dates and stratigraphic and sedimentological evidence indicate that the appearance of the Proto-Aurignacian at Bombrini dates to around 41 ky cal BP, in a phase of climatic degradation, paralleling the conditions observed for the transition at other northern Italian sites. While preliminary faunal analysis suggests little change in site use over time, the composition of the lithic assemblages point to a marked technological discontinuity between the two time periods. Riparo Bombrini's stratigraphic sequence affords important details about the environmental and cultural dynamics that marked the expansion of modern humans into Europe and the disappearance of Neandertals in that region during OIS 3. The association of a rich Proto-Aurignacian complex with an anatomically modern deciduous human tooth enhances further its importance for understanding early Upper Paleolithic in Italy.

Trace elements in modern and archaeological human teeth: Implications for human metal exposure and enamel diagenetic changes

The chemical composition of human tooth enamel from individuals born at different times and/or different geographical places can provide a record of human metal exposure through time and space. However, in addition to “in-vivo” metal exposure, post-mortem diagenetic changes can also affect the trace element composition of enamel from archaeological contexts. Modern human enamel collected from individuals born during the 20th century exhibit elevated concentrations of metals used in the industry such as Cr, Ni, Cu, Zn, and Pb when compared to archaeological enamel from disparate localities. This is a result of overall higher human exposure to industrial metals at present compared to pre-industrial times. In contrast, archaeological enamel tends to exhibit lower trace metal concentrations, however, some archaeological samples show elevated concentrations of V, Mn, Fe, REE, Th, and U relative to modern enamel. The elevated concentrations of these metals indicate post-mortem addition of elements into the preserved enamel matrix. Assuming the highest “in-vivo” human exposure to industrial metals occurred at present, we calculated maximum threshold concentrations (MTC) based on data derived from modern human enamel. Archaeological enamel samples showing concentrations for one or more of the following elements, V, Mn, Fe, REE, Th, and/or U, higher than the MTC strongly indicate modification of their trace metal compositions during the post-mortem interval. Normalization of the archaeological enamel samples concentrations for V, Mn, Fe, La, Ce, Nd, Dy, Yb, Th, and U to the MTC for these metals provides a rapid method for screening samples for diagenetic alteration.Examples of MTC evaluation of samples from several diverse archaeological contexts show that even in locations with similar age and geological context the preservation state of archaeological enamel can range from pristine, likely preserving the “in-vivo” biogenic chemical signal, to slightly altered, as a result of adsorption of redox sensitive metals, to highly diagenetically altered, apparently accompanied with cation substitution in the apatite structure. Mass-balance considerations show that the slightly altered enamel samples should still preserve the original “in-vivo” Sr isotope signal, but the Pb isotope signal may be compromised. In contrast, in the highly altered enamel samples the “in-vivo” chemical signal for a number of elements, including Sr and Pb isotopes, may well be affected by the diagenetic signal. This work demonstrates how trace element analyses can enhance isotopic analysis on tooth enamel samples from all archaeological contexts in order to evaluate the alteration status of the sample(s) under study. Such trace element screening will allow researchers to select the best preserved human enamel samples for isotopic and concentration information to decipher nutritional status, metal exposure, and geographical place of origin in past populations.

Book Review: The Anthropology of Modern Human Teeth: Dental Morphology and its Variation in Recent Human Populations

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From Neandertals to modern humans: New data on the Uluzzian.

Having thrived in Eurasia for 350,000 years Neandertals disappeared from the record around 40,000–37,000 years ago, after modern humans entered Europe. It was a complex process of population interactions that included cultural exchanges and admixture between Neandertals and dispersing groups of modern humans. In Europe Neandertals are always associated with the Mousterian while the Aurignacian is associated with modern humans only. The onset of the Aurignacian is preceded by “transitional” industries which show some similarities with the Mousterian but also contain modern tool forms. Information on these industries is often incomplete or disputed and this is true of the Uluzzian. We present the results of taphonomic, typological and technological analyses of two Uluzzian sites, Grotta La Fabbrica (Tuscany) and the newly discovered site of Colle Rotondo (Latium). Comparisons with Castelcivita and Grotta del Cavallo show that the Uluzzian is a coherent cultural unit lasting about five millennia, replaced by the Protoaurignacian before the eruption of the Campanian Ignimbrite. The lack of skeletal remains at our two sites and the controversy surrounding the stratigraphic position of modern human teeth at Cavallo makes it difficult to reach agreement about authorship of the Uluzzian, for which alternative hypotheses have been proposed. Pending the discovery of DNA or further human remains, these hypotheses can only be evaluated by archaeological arguments, i.e. evidence of continuities and discontinuities between the Uluzzian and the preceding and succeeding culture units in Italy. However, in the context of “transitional” industries with disputed dates for the arrival of modern humans in Europe, and considering the case of the Châtelperronian, an Upper Paleolithic industry made by Neandertals, typo-technology used as an indicator of hominin authorship has limited predictive value. We corroborate previous suggestions that the Middle-to-Upper Paleolithic transition occurred as steps of rapid changes and geographically uneven rates of spread.

Assessing human weaning practices with calcium isotopes in tooth enamel

Weaning practices differ among great apes and likely diverged during the course of human evolution, but behavioral inference from the fossil record is hampered by a lack of unambiguous biomarkers. Here, we show that early-life dietary transitions are recorded in human deciduous tooth enamel as marked variations in Ca isotope ratios (δ44/42Ca). Using a sequential microsampling method along the enamel growth axis, we collected more than 150 enamel microsamples from 51 deciduous teeth of 12 different modern human individuals of known dietary histories, as well as nine enamel samples from permanent third molars. We measured and reconstructed the evolution of 44Ca/42Ca ratios in enamel from in utero development to first months of postnatal development. We show that the observed variations of δ44/42Ca record a transition from placental nutrition to an adult-like diet and that Ca isotopes reflect the duration of the breastfeeding period experienced by each infant. Typically, the δ44/42Ca values of individuals briefly or not breastfed show a systematic increase during the first 5-10 mo, whereas individuals with long breastfeeding histories display no measurable variation in δ44/42Ca of enamel formed during this time. The use of Ca isotope analysis in tooth enamel allows microsampling and offers an independent approach to tackle challenging questions related to past population dynamics and evolution of weaning practices in hominins.

Using Carbon, Oxygen, Strontium, and Lead Isotopes in Modern Human Teeth for Forensic Investigations: A Critical Overview Based on Data from Bulgaria.

Isotopic data obtained from human remains can provide information about an individual's origin, migration, and diet. We evaluate the usefulness of carbon, oxygen, strontium, and lead isotopes for forensic investigations by comparing data from Bulgarian teeth with data from other regions. Geo-referencing based on oxygen or strontium isotopes can be misleading due to overlap with other countries in Europe and other continents. Carbon and lead isotopes, in combination with oxygen and strontium isotopes, provide the most useful information for identification of local vs foreigner status. In particular, high-precision Pb isotopes show a distinct "Bulgarian" range; however, it is possible that individuals from other countries in Eastern Europe and/or central to western Asia could have overlapping isotopic values. Additional high-precision multi-isotope data from modern humans from different regions in the world are required to transition from speculative to more quantitative estimation of a geographical place of origin for unidentified human remains.

Bondi Cave and the Middle-Upper Palaeolithic transition in western Georgia (south Caucasus)

Abstract The late Pleistocene expansion of anatomically modern humans (AMHs) into Eurasia and the concurrent demise of the Neanderthals appears to be a complex and regionally variable process. The southern Caucasus region, with its rich cave-sites, has recently provided important results regarding this process. In this paper we report on the results of fieldwork in Bondi Cave, Western Georgia, providing a new radiocarbon chronology, stratigraphic observations, analyses of lithic technology and provenance, faunal and floral remains as well as paleoenvironmental data. The cave includes Middle Palaeolithic (ca, 45,000 ka cal. BP) cultural horizons and a long Upper Palaeolithic sequence (ca. 40,000–27,000 cal. BP from layer V to IV). A modern human tooth was found in layer Vb. We estimate its age at 39,000–35,800 Cal BP (95.4%), based on the Bayesian age model we built. If the context of the tooth is reliable, as we think it is, this would make it the oldest morphologically modern human in the Caucasus. Upper Palaeolithic hunting of tur and bison, as well as the collection of various plants including flax is attested. Mobile Upper Palaeolithic foragers inhabited the cave in generally cold and dry periods, but a mosaic of environments, including forests and meadows, was nonetheless available to them. The archaeological sequence of Bondi and adjacent sites indicates a substantial time gap between the Middle and Upper Palaeolithic occupations, thus disproving Neanderthal-AMH interaction in this area and lending support to a replacement scenario in the southern Caucasus, assuming of course that the Early Upper Palaeolithic (EUP) is related to the arrival of AMHs.

Palaeoanthropology: Homo sapiens in China 80,000 years ago.

A discovery in southern China of human teeth dated to more than 80,000 years old indicates that Homo sapiens was present in the region considerably earlier than had previously been suspected. See Letter p.696 A collection of 47 anatomically modern human teeth from the Fuyan Cave in Daoxian, southern China, shows that anatomically modern humans were in the region at least 80,000 years ago, and possibly as long as 120,000 years ago. That is 30,000–70,000 years earlier than in the Levant and Europe. These people were much more modern-looking than hominins in northern and central China. The discovery adds to the complexity of the human story and shows that much remains to be discovered.

Using elliptical best fits to characterize dental shapes.

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.