Incisor microwear textures of five bioarcheological groups

Dental microwear texture analysis has proven to be a valuable tool for inferring aspects of subsistence behaviour in human groups and diet in other mammals. Studies have to date been limited to molar teeth. Here we report on the first microwear texture analysis of incisors. Five bioarcheological groups were included in this analysis: Aleuts from various islands in the Bering Sea (n = 24), Arikara from the Mobridge site in South Dakota (n = 18), ethnic Chinese cannery workers from Kodiak Island (n = 16), a Late Woodland Bluff sample from Jersey County, Illinois (n = 18) and Puye Pueblo from Pajarito Plateau in New Mexico (n = 18). First, point clouds with 0.18 µm lateral spacing and 0.005 µm vertical resolution were obtained from maxillary central incisor labial surfaces using a white‐light confocal profiler. Four adjoining fields were sampled for a total area of 276 µm × 204 µm for each specimen. Surface data were then imported into scale‐sensitive fractal analysis software for texture characterisation. Results indicate significant variation among groups in anisotropy, fill volume and heterogeneity. These differences are likely related to differences in diet, degrees and types of non‐dietary incisor use, as well as exposure to abrasives. This study also suggests that texture variables most useful for characterising and comparing incisor microwear may differ from those most useful for distinguishing molar microwear patterns. Copyright © 2009 John Wiley & Sons, Ltd.     

Incisor labial surface wear striations in modern humans and their implications for handedness in Middle and Late Pleistocene hominids

Over the past four decades several workers have argued that the orientations of striations on the labial surfaces of the front teeth of Middle and Late Pleistocene fossils attributed to Neanderthals and antecedent archaic hominids can tell us something about handedness. These researchers have suggested that such scratches result from stone tools scraping across the incisors during ‘stuff‐and‐cut’ behaviours, and that they reflect directions of hand movements and handedness. In this study, we examine comparable wear features on the incisors of anatomically modern humans to determine whether striation angle may reflect handedness. The teeth from 66 individuals representing four groups with known differences in subsistence practices (Aleut, Arikara, Illinois Bluff, and Puye) were examined. Photomicrographs were made of the maxillary central incisor labial surfaces of all individuals at 56× magnification. These photomicrographs were scanned to image files, and orientations of all visible wear striations were measured using a semi‐automated image analysis procedure. Approximately three‐quarters of all labial surfaces showed a preferred striation orientation. Of those, most had preferred apico‐cervical or vertical striation orientations, independent of cultural affiliation. Few showed the tendency toward diagonally‐oriented scratches expected if handedness is related to scratch orientation. We found no evidence for ‘stuff‐and‐cut’ striations, despite the fact that at least one of the groups studied—the Aleut—are documented to have used this behaviour. In sum, there is evidently no relationship between striation orientation and handedness in the groups studied. It is, therefore, unlikely that labial scratch orientation in Middle and Late Pleistocene hominids reflects handedness if they used their front teeth in a manner comparable to that of any of the anatomically modern groups considered here. Copyright © 1999 John Wiley & Sons, Ltd.     

The Retromolar Space: A Morphological Curiosity Observed Amongst the Protohistoric Arikara and Mandan

The retromolar space (RMS), defined in palaeoanthropology as a space posterior to the third molar, between the distal edge of the tooth and the anterior margin of the ascending ramus when the mandible is held in lateral view, has been described as an autapomorphic trait unique to Neanderthals despite its presence in anatomically modern humans. This study examined RMS prevalence in a sample of protohistoric Arikara and Mandan Amerindians to determine what craniofacial morphology is correlated with the RMS. It was hypothesised that the feature would be present in the Amerindians studied and associated with a long cranial length, a large nasal height, midfacial prognathism, a broad mandible, and dental wear. The results indicated that RMSs were present in the Arikara and Mandan and significantly correlated with cranial length, cranial breadth, nasal height, bizygomatic breadth, basion‐nasion length, basion‐nasiospinale, mandible length, gonial angle, bigonial breadth, and dental wear. Thus, RMSs are associated with a dolichocephalic skull, wide cranial and facial breadth, a prognathic face, large nose and a corresponding wide and long mandible with a reduced gonial angle. This suggests that the RMS is the result of these features merging together in the craniofacial complex and should not be considered a Neanderthal autapomorphy. Copyright © 2015 John Wiley & Sons, Ltd.     

Patterns of social identity in relation to tooth ablation among prehistoric Jomon foragers from the Yoshigo site,Aichi prefecture,Japan

This study documents and interprets patterns of identity in relation to tooth ablation patterns at Yoshigo, a Late/Final Jomon period (3500–2500 yBP) site. Two patterns of tooth ablation are observed among the Yoshigo people: both (2) mandibular canines or four (4) mandibular incisors were extracted during life and formed a basis for identity differentiation. Three hypotheses are tested regarding these groups: (1) tooth ablation groups will be unrelated to postmarital residence; (2) tooth ablation groups will be associated with age‐based achievements; (3) tooth ablation groups will be associated with occupational specialisation. Biodistance, demographic and stable isotope analyses were performed on skeletal remains recovered from Yoshigo (3500–2300 BP) to test these hypotheses. Within‐group variation expressed by cranial and dental measurements was not significantly different between tooth ablation groups. This indicates that tooth ablation practices were not related to migration. Previous biodistance findings do, however, suggest that tooth ablation groups represent closely related individuals, possibly kin‐based networks. Demographic analysis of age‐at‐death and tooth ablation suggests that tooth ablation styles were achieved at different ages. Stable isotope analysis indicates that the tooth ablation groups consumed similar foods. Based on isotopic findings from other sites and archaeological evidence for food sharing among Jomon people, these results suggest that dietary variability between tooth ablation groups was homogenised by cooperative food sharing. The totality of these findings support the hypothesis that the identities associated with tooth ablation were unrelated to migratory patterns, and instead, possibly reflect kin‐based social units, where achievement or age acted as a determinant of membership. Copyright © 2010 John Wiley & Sons, Ltd.     

Occlusal molar microwear and the diets of the Ipiutak and Tigara populations (Point Hope) with comparisons to the Aleut and Arikara

Archaeological excavations at Point Hope, Alaska uncovered skeletal remains of two populations: the Ipiutak (100 B.C.–500 A.D.) and Tigara (1200–1700 A.D.). Archaeological evidence indicates that, although both groups relied on animal (largely marine) resources for their subsistence, the Ipiutak were mainly caribou hunters, whereas the Tigara were primarily whale hunters. To date, no study has attempted to ascertain whether the inferred dietary differences of these two groups could be substantiated using a more direct technique, e.g. microwear or stable isotope analysis. In this study, the occlusal molar microwear fabrics of the Ipiutak and Tigara were analyzed. Comparative data for two other modern human groups, the Aleut and Arikara, were also examined. Significant differences in microwear signatures were detected among the groups considered. The results of this study show that the Tigara have significantly more microwear features, more pits and narrower scratches compared to the Ipiutak. These results are concordant with interpretations that the two Point Hope populations had significantly different dietary habits. Differences in microwear signatures between the Aleut and the two Point Hope populations were also detected. Compared to the two Point Hope populations, the Aleut has significantly fewer features and wider scratches. The Aleut microwear signature further differs from that of the Tigara in having significantly lower pitting incidence. The microwear pattern of the Arikara, who had a mixed diet, differed from that of the mainly meat-eating Aleut and Point Hope peoples in that the Arikara has significantly fewer features, lower pitting incidence and narrower scratches.     

A Bioarchaeological and Biogeochemical Study of Warfare and Mobility in Andahuaylas,Peru (ca. ad 1160–1260)

Warfare impacts how people and populations can move about the landscape. Ethnographers have posited that internal warfare, conflict that takes place within a single society, is strongly associated with female abduction. In contrast, external warfare, combat between different societies, is often accompanied by the in‐migration of men for purposes of defence. To test this assertion, we evaluate human remains from one of the most violent eras in Andean prehistory, the Late Intermediate Period (ad 1000–1400). In the south‐central highlands of Andahuaylas, Peru, this era witnessed the coalescence of two formidable polities, the Chanka and the Quichua. Ethnohistoric accounts describe internal warfare among the Chanka and external warfare between the Quichua and their neighbours. In this study, bioarchaeological and biogeochemical methods are marshalled to elucidate ancient patterns of violence and mobility with greater nuance. We employ strontium isotope analysis of tooth enamel apatite to inform on residential origin, and we reconstruct patterns of violent conflict through analysis of cranial trauma. In all, 265 crania were excavated from 17 cave ossuaries at two Chanka sites and one Quichua site. Data were collected on age, sex and cranial modification—an indicator of social identity and cranial trauma. A representative subsample of molars from 34 individuals subjected to strontium isotope analysis demonstrates that among the Chanka, violence was significantly directed towards social groups within society, marked by modified crania. The presence of two nonlocal women with signs of increased morbidity and mistreatment points to possible mobility‐by‐abduction. In contrast, among the Quichua, men have significantly more trauma, and wounds are concentrated on the anterior. Trauma on women is lower, nonlethal, and concentrated on the posterior. This divergent pattern is commonly observed in external warfare (raids and community defence), where men face attackers and women escape them. The presence of two nonlocal men supports a mobility model of strategic in‐migration. In sum, osteological and isotopic data sets are shown to reveal divergent life‐course experiences not captured by the archaeological data or historic records alone. Copyright © 2014 John Wiley & Sons, Ltd.     

Masticatory and non‐masticatory dental modifications in the epipalaeolithic necropolis of Taforalt (Morocco)

In this study, we used standardized methods to investigate masticatory and non‐masticatory dental alterations (chipping, notches, interproximal grooves) in teeth from the epipalaeolithic necropolis of Taforalt (Morocco, about 12,000–11,000 BP). The particular distribution of some of the alterations could be related to avulsion of the upper central incisors, a systematic ritual characterizing all adult individuals of the necropolis. Because of this practice, the functions of the anterior teeth (cutting and tearing portions of food while eating, holding objects, etc.) likely shifted to the posterior teeth. Copyright © 2004 John Wiley & Sons, Ltd.     

Interpreting Oral Pathology at Machu Picchu,Peru

This study analyzes oral pathological conditions—caries, antemortem tooth loss, and occlusal macrowear—among adults (N = 70) interred at Machu Picchu, Peru. Previous isotopic diet reconstructions at Machu Picchu suggest substantial early‐life variation that may have narrowed somewhat by the last decade of life. This study seeks to further elucidate the intersection of diet, sex, and health at Machu Picchu by analyzing oral pathological conditions with existing carbon and nitrogen isotopic data. Observed caries prevalence is corrected to control for age and tooth loss, and is described for both anterior and posterior teeth; wear data are scored and reported for individual tooth types. Results indicate caries prevalence consistent with carbohydrate‐rich diets and no significant difference between males and females. However, no significant isotopic parameters are associated with caries prevalence in young adult males, while caries prevalence is significantly associated only with enamel carbonate δ¹³C in older adult males. Dietary protein sources, but not C₄ resources, are associated with caries prevalence in young adult females, and to a lesser degree in older adult females. Significant associations between occlusal wear and caries exist among young adult males and young adult females, but involving different tooth types. These findings suggest differential protein consumption at Machu Picchu between males and females, and separate masticatory and physiological processes shaping caries prevalence between the sexes at the site. This study therefore underscores the role that gender roles may have played in diet variation among this population and the need to account for sex in analyzing oral pathology. Copyright © 2013 John Wiley & Sons, Ltd.     

Tooth Evulsion in the Maghreb: Chronological and Geographical Patterns

The practice of tooth evulsion was widespread in the Maghreb from the Iberomaurusian through to the Neolithic. We present an updated summary of the geographical and chronological distribution of different patterns of tooth evulsion during this period based on a site-by-site review. Tooth evulsion was almost universal during the Iberomaurusian but typically restricted to the upper central incisors. During the Transitional Epipalaeolithic, the practice was extended to include removal of a minimum of four central incisors in both males and females. During the Capsian the custom became less prevalent and more variable, suggesting regional difference and a possible change or diversification of social meaning. A markedly higher prevalence of tooth evulsion among females during the Capsian period supports this interpretation. The prevalence of tooth evulsion was further reduced in the Neolithic.     

Age at death estimates for the protohistoric Arikara using molar attrition rates: A new quantification method

Dental attrition is positively related to ageing and has often been used to determine age at death of animals and prehistoric/historic humans. A newly designed molar-attrition-scoring standard was applied to a protohistoric skeletal sample, the Arikara (N = 143) from the North American Plains. Several criteria are used in producing a molar tooth crown wear (MTCW) score. These include: (i) the size of enamel wear facets, (ii) the amount of dentine and secondary dentine exposure, (iii) the height of the tooth, (iv) the enamel rim thickness, and (v) the amount of pulp-cavity exposure in the advanced stages. Age-at-death estimates were generated from ordinary least-squares (OLS) analysis, with estimated age regressed independently on the total molar attrition score (TMAS), mean molar-1 tooth crown wear (ȲM1TCW), mean molar-2 tooth crown wear (ȲM2TCW), and mean molar-3 tooth crown wear (ȲM3TCW). In all analyses (with the exception of the third molar), the coefficient of determination (r²) revealed a strong relationship between molar attrition and age. Multiple-regression analysis revealed a significant sex difference in molar-attrition rates. Besides intercept and slope differences, the female scatter showed greater molar attrition variation than the male scatter. There was no statistical difference between mean upper molar attrition score (UMAS) and lower molar attrition score (LMAS). There was no significant difference in molar attrition rates by side, and side by molar tooth.     

Pits and pitfalls: taxonomic variability and patterning in tooth mark dimensions

Archaeologists use experimentally derived tooth mark frequencies, locations, and size data to infer (a) the extent of carnivore involvement in the formation and modification of faunal assemblages, (b) the size classes of predators marking those assemblages, and (c) whether hominins accessed fleshy or defleshed carcasses (Blumenschine and Pobiner, 2007; Dominguez-Rodrigo et al., 2007). These inferences are often debated in part because frequency counts can vary widely among observers and because the carnivore taxa for which tooth mark dimensional data are available are limited. This study contributes to the body of actualistic/experimental tooth mark data and presents a methodology for collecting these data. We offer a greatly simplified method that may encourage others to collect and quantify tooth mark dimensions. We present dimensional data from feeding experiments with 16 omnivore and carnivore species of known age and mass, ranging in size from skunks to tigers, significantly expanding the taxonomic and size range of carnivores for which we have tooth pit data. Our results demonstrate considerable, but not complete, overlap in tooth pit dimensions among size, class, and taxon. Tooth mark dimensions on epiphyses and metaphyses were relatively strongly correlated with body mass, whereas diaphyseal tooth marks exhibited the weakest correlation. Human consumption of animal tissue produced tooth marks comparable in size to medium felids and small canids, suggesting the possibility that some tooth marks on Early Stone Age (ESA) faunal assemblages could, as suggested by Oliver (1994), result from small carnivore and/or hominin consumption.     

Health Consequences of European Contact in the Great Plains: A Comparison of Systemic Stress Levels in Pre‐ and Post‐Contact Arikara Populations

The biocultural effects of European contact varied considerably throughout the Americas. Some populations were decimated by colonialism, while others benefited from trade relationships and access to new technologies. It has been suggested that initial contact with European fur traders and explorers was economically favourable for Plains village populations, thereby facilitating a period of cultural florescence. In this study, we evaluate the hypothesis that Plains groups were better off than their predecessors during the initial contact period by comparing frequencies of enamel hypoplasia, cribra orbitalia, and porotic hyperostosis in pre‐ and post‐contact Arikara skeletal assemblages. We included both juveniles and adults in our sample to capture variation in the stress experience of different segments of the population. Our analysis revealed similarly low frequencies of cribra orbitalia in the pre‐ and post‐contact groups and no observed cases of porotic hyperostosis. Enamel hypoplasia, however, was significantly more prevalent among post‐contact Arikara villagers when compared to their pre‐contact counterparts, which suggests that stress levels were higher after European contact. Additionally, enamel hypoplasia was most common among post‐contact juveniles. The elevated frequency of enamel hypoplasia in the post‐contact sample combined with the low frequencies of cribra orbitalia and porotic hyperostosis suggests that disease stress, rather than nutritional deficiencies, was likely responsible for the decline in overall health following European contact. These results also suggest that juveniles are sensitive indicators of systemic stress within a population and should be included in bioarchaeological analyses of prehistoric health when available. Copyright © 2015 John Wiley & Sons, Ltd.     

Periapical lesions and dental wear in the early Maori

Dental wear and intrabony lesions were evaluated in a sample of 225 skulls (136 male) of pre‐contact New Zealand Maoris. The degree and direction of surface wear was scored according to the method of Molnar ( Molnar 1971 . Human tooth wear, tooth function and cultural variability. American Journal of Physical Anthropology34: 175–190) and revealed severe surface loss in both males and females with horizontal wear being the dominant pattern (62.4% male, 57.5% female). The width of coronal tissue above the pulp chamber, as well as the maximum depth and width of periapical lesions, was measured from both standard radiographs and digital images. The high prevalence of periapical pathology in the Maori underlined the extreme nature of dental wear in these people. It is postulated that this degree of tooth loss may be attributable to a change in diet from large birds to marine‐dependence, the introduction of the kumara to New Zealand, dental erosion and finally, to the excessive masticatory forces exerted by a robust facial complex on normally sized teeth. Fenestrated lesions were highly prevalent (83% of skulls) and were centered mostly on the maxilla, with an even distribution among tooth classes. The finding of periapical lesions in teeth with minimal observable wear was attributed to traumatic occlusion. Copyright © 2001 John Wiley & Sons, Ltd.     

A taphonomic study of bone modification and of tooth‐mark patterns on long limb bone portions by suids

This work presents new taphonomic data on bone modification by suids, including domestic pig, wild and hybrid boars. The intense modification undergone by bones from animals smaller than 100 kg is shown, together with a more moderate modification on bones from larger animals. Both the ravaging pattern (with preferential deletion of cancellous tissue) and the tooth‐marking frequencies are similar to those documented among hyenas and dogs when having primary access to complete bones. A dual‐patterned experimental model consisting of the interaction of humans and suids was also considered. Here it is shown how suid modification of hammerstone‐broken bone assemblages is different from that documented among canids and hyaenids, as experimentally replicated. These results increase the number of non‐anthropogenic bone‐modifying agents and posit new issues on equifinality processes. Copyright © 2008 John Wiley & Sons, Ltd.     

Temporal changes in Arikara humeral and femoral cross-sectional geometry associated with horticultural intensification

Humeral and femoral cross-sectional properties from three archaeological variants of the Arikara, an American Great Plains Indian tribe, were analyzed for temporal (16th to 19th centuries) changes in long bone architecture, asymmetry, and sexual dimorphism associated with intensification of horticulture during the late protohistoric and early historic periods. There were a number of significant changes in long bone, especially femoral, cross-sectional morphology and asymmetry among females through time that probably reflect increases in the workload necessary to produce surplus crops. Changes in long bone architecture among males are restricted to the humerus and may reflect a greater reliance on firearms. The pattern of sexual dimorphism also changes through time among the Arikara due to a combination of environmental (nutrition and disease) and mechanical factors.     

Dental chipping: Contrasting patterns of microtrauma in inuit and European populations

While the study of dental wear has enjoyed wide popularity for over 100 years, dental chipping, or microfractures of the tooth crown, has received little attention. Observations on dental chipping in populations from the Arctic (St. Lawrence Island, Alaska) and Europe (medieval Norway and Spain) reveal patterns of microtrauma that provide insights into the dietary and tooth‐tool use behaviour of earlier populations. St. Lawrence Island Inuit, with an emphasis on consuming tough and frozen foods, in combination with extensive tooth‐tool use, exhibit a pattern of chipping that is characterised as ‘molar dominant’. The two European samples exhibit an ‘incisor‐dominant’ pattern but contrast markedly in frequencies, with medieval Norwegians showing significantly more chipping than medieval and post‐medieval Spanish. The systematic study of chipping promises to provide a new perspective on how populations used and/or abused their dentitions in earlier times. Copyright © 2010 John Wiley & Sons, Ltd.     

A Study of the Potential of Deciduous Incisor Wear as an Indicator of Weaning Using a Human Skeletal Population

The aim of this work is to investigate the potential of wear on the earliest erupting teeth, the deciduous central incisors, for studying weaning in human skeletal populations. The study group is from mediaeval Wharram Percy, where existing δ¹⁵N data indicate cessation of breastfeeding occurred by about 24 months post‐partum. The hypothesis tested is that there should be an increase in dental wear as breast milk is replaced with solid foods during weaning. Incisor wear is monitored using crown heights, measured from photographs using image analysis. Results provide little evidence for alteration in incisor wear rates with the attenuation of breastfeeding, perhaps because abrasive foods were used as supplements well before breastfeeding declined. Copyright © 2015 John Wiley & Sons, Ltd.     

Rickets and child abuse: the case of a two year old girl from the 4th century in Lisieux (Normandy)

The burial of a child of two years of age from the 4^th century site of Lisieux‐Michelet (Calvados, France) was examined for bone hyperplasia and a variety of mechanical deformations recognized in association with skeletal trauma. Results of DNA analysis of bone using the PCR method identified this child as female. Microscopic features of the teeth (interglobular dentine) and a sample taken from the tibia conclusively determined that this child suffered from vitamin D‐resistant rickets and possibly X‐linked hypophosphataemic rickets as its most common form of occurrence. In addition, evidence for child abuse is suspected based on the presence of cranial and tooth fractures and the appearance of successive plaque‐like endocranial (meningeal) appositions. This is the first palaeopathological report of child abuse in antiquity. Copyright © 2002 John Wiley & Sons, Ltd.     

A possible massacre at Early Bronze Age Titriş Höyük,Anatolia

Trauma is among the most important sources of data providing information related to systematic violence, battles and massacres among ancient populations. In this study, a mass grave from Titriş Höyük in the Southeast Anatolia was examined in terms of cranial traumas. Skeletal remains of minimum 19 individuals were placed on a plaster basin as a secondary interment. The frequency of cranial trauma was 81.3% among 16 available adult crania. The fact that the perimortem traumas were observed on both sex groups and the presence of two children and an infant on the basin suggest the possibility of these individuals being subjected to an attack or a massacre. It has been determined that the frequency of traumas in the common burials increased more than twofold from Early‐Mid EBA (6.7%) to Late EBA (14.3%). While all of the injuries observed in Early‐Mid EBA were in the form of healed depressed trauma, penetrated traumas were also encountered in Late EBA. The increased frequency of cranial trauma with unusual interment on a plaster basin indicated that a social stress might have taken place in Titriş Höyük. It is concluded that the collapse of the Akkadian Empire, the deterioration of the trade‐based economy and resource stress might have been possible factors that played a role in the excessive violence, or a massacre in Titriş Höyük. Copyright © 2010 John Wiley & Sons, Ltd.     

Αge‐associated Variation and Sexual Dimorphism in Adult Cranial Morphology: Implications in Anthropological Studies

The current paper explores the impact of age and sex on adult cranial shape and size variation in the documented collections from St Bride's and Spitalfields. The scope is to assess the extent to which it is valid to pool age and sex groups in inter‐population comparisons that use cranial data. For this purpose, age and sex differences in cranial shape and size were explored using multivariate analysis of variance, Discriminant analysis and Mann–Whitney tests. The results suggest a clear change in cranial shape with increasing age; however, this change is not statistically significant. Therefore, it is justifiable to pool different age groups in bioarchaeological analyses. Increasing age also has a minimal impact on cranial size among females, whereas among males, its impact is small but statistically significant. Finally, cranial shape and size are significantly different between males and females, irrespective of their age. This dimorphism can be used for the assessment of sex, although attention should be given to over‐classification problems when using discriminant analysis. Copyright © 2012 John Wiley & Sons, Ltd.