Developmental abnormalities of the permanent dentition in prehistoric Ohio Valley Amerindians

The frequencies of developmental abnormalities in size, shape, number of teeth, and enamel formation are presented for a sample of 389 prehistoric Ohio Valley Amerindians from the following cultural complexes: Glacial Kame, Adena, Ohio Hopewell, Cole, Fort Ancient, and Erie (Whittlesey Focus). In addition, the magnitude of fluctuating asymmetry is determined for each tooth and for individuals of these groups. Tests of association indicate complexes with Late Diffuse economic adaptations (Glacial Kame, Adena, Hopewell) exhibit significantly higher frequencies of numerical abnormalities of M₃ and M³ enamel pearls, while Late Focal complexes (Cole, Fort Ancient, Erie) exhibit a higher frequency of severe, general linear enamel hypoplasia. The magnitude of fluctuating asymmetry is, however, generally the same in the Late Diffuse and Late Focal groups. The occurrence of two rare abnormalities with large genetic components, essentially limited to one Hopewell and one Adena mound, raises the possibility that the individuals interred in these mounds are biologically related. Since it is widely held that mound burials represent a status class of the population, it is likely that the Late Diffuse sample is biased in favor of a number of highly select population segments each of which contains biologically related individuals. Accordingly, the lower frequency of severe, general linear enamel hypoplasia in Late Diffuse groups is hypothesized as the result of the more advantageous circumstances expected for high status individuals, and the higher frequencies of numerical abnormalities of M₃ and M³ enamel pearls are hypothesized primarily as the result of mitigated selection on masticatory complex integration, and/or a biased sample. Comparisons with the deciduous dentition show the permanent teeth exhibit higher frequencies of developmental abnormalities. This result is explicable in terms of the more favorable developmental environment of the primary teeth, or a stronger developmental canalization.     

Evolution of the dentition in prehistoric Ohio Valley Native Americans: II. morphology of the deciduous dentition

In order to evaluate the microevolutionary dynamics of morphological features of the deciduous dentition, I collected data on the variation of 57 features (33 crown and 24 root) from prehistoric Ohio Valley populations. I sampled a total of 370 individuals from 26 populations representing a lineage that inhabited the middle and upper Ohio valley region from approximately 3000 to 350 BP. Evolutionary changes in the frequencies of morphological features of the deciduous teeth in this lineage were limited. Over 80% of the features show no significant differences among the populations. The relatively few features that show consistent differences separate pre- and postmaize agricultural populations. I discuss explanations for this change in terms of selection differences or gene flow. The general pattern of morphological trait expression in the deciduous teeth of this Ohio Valley lineage corresponds to what has been termed the Mongoloid dental complex (sinodonty in the permanent teeth). I suggest additional features that, with further study, may be added to this morphological complex. Am J Phys Anthropol 106:189–205, 1998. © 1998 Wiley-Liss, Inc.     

Evolution of dentition in prehistoric Ohio Valley Native Americans III. Metrics of deciduous dentition

Deciduous tooth size in Native Americans of the Ohio Valley area is fairly stable from the terminal Late Archaic (3200 BP) through the Late Prehistoric (350 BP) periods. Some fluctuation in average size did occur during this time. These fluctuations most likely reflect random changes due to gene drift. However, no difference in the pattern of interactions among the sizes of teeth (covariance structures) can be demonstrated during this period. Principal components analysis of the buccolingual and mesiodistal dimensions in the total sample indicate that the major axis of deciduous tooth size in the Ohio Valley population shows an allometric relationship, with the dimensions of the anterior teeth increasing (or decreasing) as the 1.33 power of the dimension of m1(1) and as the 2.0 power of the dimension of m2(2). Comparison of the Ohio Valley samples with other samples from the Eastern Woodlands suggests that geography may have played a minor role in structuring deciduous tooth size variation. For the most part, however, widely separated Eastern Woodlands populations appear to have been evolving independently with respect to deciduous tooth size.     

A descriptive and comparative study of the deciduous dentition of prehistoric Ohio Valley Amerindians

The deciduous dentition of 58 individuals from groups of prehistoric Ohio Valley Amerindians (2,000 B.C.-1,600 A.D.) was measured for antero-posterior and bucco-lingual dimensions and scored for morphological characteristics and macroscopic pathology. Only five dimensions of the posterior teeth and the frequency of severe linear enamel hypoplasia showed significant differences in the groups. In all cases focal agriculturalists exhibited smaller teeth and a higher frequency of severe linear enamel hypoplasia. These findings are explained as the result of changing diet and food preparation techniques, and/or sampling bias in the earlier burial cult groups where primarily higher status individuals may be the representatives. Comparison of metric and morphological characteristics of the deciduous dentition in the prehistoric Amerindians and roughly contemporaneous European groups indicates morphological characteristics are the better means of discrimination.     

Family studies of tooth size factors in the permanent dentition.

Correlations between dimensions of the permanent teeth in Australian Aboriginals were studied by factor analysis to disclose the main sources of shared variability. Findings indicated that in both males and females most of the common variability in the tooth dimensions could be accounted for by factors representing mesiodistal size of anterior teeth, buccolingual size of anterior teeth, generalized size of the premolars and generalized size of the molars. Factor scores derived from the analysis were used to calculate intraclass correlations among brothers and among sisters. These correlations tended to be higher for the factors contributing most to the common variability indicating that the factors might represent fields under direct genetic control. There was no trend for intraclass correlations among siblings derived from multivariate scores to be consistently higher than those based on observed tooth dimensions. The main advantage to the user of factor analysis is the ability to interpret associations between interrelated variables more objectively than is possible by conventional correlation methods.     

Morphologic characteristics of the Alaskan Eskimo dentition. III. Number of cusps on the upper permanent molars

A study of 35 coastal and 64 inland Alaskan Eskimos revealed a reduction in the number of cusps from the first to the third maxillary molar. While 97% of the first molars had four cusps, only 39.6% of the second molars and 15.2% of the third molars had that number. The reduction occurs through elimination of the hypocone. No statistically significant sex difference in the trend towards reduction in the cusp numbers was found. In the inland female group the occurrence of four cusps in the maxillary second molar was statistically higher than in the coastal female group. This may be due to a more pronounced racial admixture of white people along the coast. A similar difference, although not statistically significant, was found in the corresponding male groups. Alaskan Eskimos have a tendency towards a lower frequency of four cusps on all three maxillary molars than Aleuts. Only the second molar exhibited a statistically significant difference in this respect. A statistical evaluation revealed that in the Alaskan Eskimo maxillary first and third molars the reduction of cusps is independent of the size and form of the molars and of the suppression of the third molar. For the second molar, however, the groups with four well-developed cusps showed significantly larger buccolingual diameter.     

Differences in interproximal and occlusal tooth wear among prehistoric Tennessee Indians: implications for masticatory function

Breadth of the interproximal wear facet between lower P2 and M1 and between lower M1 and M2 was measured in human skeletal samples representing the Archaic, Woodland, and Mississippian periods of Tennessee River Valley prehistory, with the aim of assessing relative magnitudes of applied masticatory forces. When stratified by level of occlusal wear, mean interproximal facet breadth was consistently larger in the Archaic sample than in the Mississippi sample, with the Woodland sample intermediate. An analysis of covariance demonstrated that there was significant (p less than or equal to 0.01) differences in facet size among the three groups even when differencs in crown breadth were taken into account. Similar results were obtained in regressions of facet size on chronological age (Archaic larger than Mississippian at P less than or equal to 0.01). Since rate of occlusal wear appears to be somewhat greater in the Archaic sample than in the later samples, the differences in interproximal wear are probably underestimated. It is suggested that the high levels of interproximal wear in the Archaic are indicative of the large occlusal forces and repetitive chewing required to masticate a diet of seeds, wild plant foods, and small animals, for which prior preparation (e.g., grinding, cooking) was minimal or nonexistent (as indicated by paleofecal samples). The lower amounts of interproximal wear observed in the Woodland and Mississippian samples imply considerable reductions in strenous mastication, perhaps due to the widespread adoption during these period of pottery and the earth oven, together with ethnographically-documented techniques of food preparation that transformed most foods to a soft consistency.     

Phenotypic selection on the dentition in a Late Archaic population of Ohio

Significant phenotypic selection acting on the buccolingual diameters of the permanent first and second molars is established for a Late Archaic population in Ohio. Directional selection appears to be acting on an index that increases the size of the maxillary first (UM1) and mandibular second (LM2) molars and decreases the size of the maxillary second (UM2) and mandibular first (LM1) molars. Variance selection is fundamentally disruptive but results in a more integrated (highly correlated) set of characteristics in the after-selection sample.     

Dental caries, enamel composition, and subsistence among prehistoric Amerindians of Ohio

Six populations of prehistoric Amerindians from Ohio are sampled to establish the relationship of enamel composition and dental caries experience. The populations used included groups practicing hunting-gathering-fishing and maize horticulture, and they represent at least two major cultural traditions, the Late Archaic/Glacial Kame (1000-500 BC) and the Fort Ancient and Sandusky Bay Traditions (AD) 1200-1600). Characterization of enamel composition is achieved using scanning electron microscopy energy-dispersive X-ray analysis. Thirteen elements present are quantified, and they are analyzed with respect to each population's subsistence base using correspondence analysis. Evaluations of cariogenic and cariostatic effects of elements are made on the basis of caries frequency comparisons among the populations. Results indicate that zinc, copper, iron, nickel, and calcium-phosphorus ratio distinguish populations exhibiting high, moderate, and low caries frequency as well as discriminate hunter-gathers from maize horticulturalists.     

The role of changing childhood diets in the prehistoric evolution of food production: An isotopic assessment

Earlier weaning has often been suggested as a cause for population growth after the evolution of food production. However, evidence for weaning-time reduction is largely circumstantial. Collagen stable nitrogen- and carbon-isotope ratios from juvenile and adult burials from four sites in eastern North America were measured to estimate weaning onsets and durations before and after the appearance of intensive food production. Two preagricultural Late Archaic sites (Indian Knoll and Carlston Annis) are compared with two highly agricultural Middle Mississippian sites (Angel and Tinsley Hill). Isotopic data and paleodemographic measures of birth rates provide no evidence for changes in weaning behavior or fertility with the development of food production in the prehistoric Lower Ohio Valley. Birth rates and weaning behavior appear to have been roughly the same at all four sites. These results indicate that models attributing population growth after the appearance of food production to earlier weaning are not universally applicable.     

An analysis of cercopithecoid odontometrics. I. The scaling of the maxillary dentition.

The relations between two tooth indices, post-canine area and incisor width in the upper jaw, and three variables, diet, body weight and body weight dimorphism, were examined separately for the males and females of 29 cercopithecoid species. Each species was assigned to one of three diet classes (folivore, frugivore, omnivore). Data on the other variable consisted of species means (log-transformed) obtained from published sources. The analytic techniques used were bivariate and multiple regression, the tooth indices being the dependent variables. All tooth indices scaled isometrically within diet classes, and all except female incisor width scaled with positive allometry across diet classes. In both sexes, the body weight adjusted mean incisor width of folivores was significantly smaller than that of either frugivores or omnivores. In the females, the body weight adjusted mean post-canine areas did not differ significantly across diet classes, while in the males the omnivores had a larger body weight adjusted mean post-canine area than either the folivores or frugivores. Female post-canine area was the only tooth index for which body weight dimorphism was a significant predictor. Extrapolations of these findings to other extant and to fossil primate species are discussed.     

Congenital defects of the upper lateral incisors (ULI) and the morphology of other teeth in man

A sample of 192 male propositi with at least one ULI either missing or reduced has been compared with 197 male controls in terms of the morphology of the other teeth. Every class of propositi exhibits modifications in the following characters: Significant differences between propositi and controls were found for molar cusp number and groove pattern, particularly in the lower first molar and in propositi with reduced ULI. Significant differences between propositi and controls were also found with respect to caniniform pattern of the lower first premolar. The Carabelli's cusp is rarer in propositi. A hypothesis to account for these observations is proposed.     

Task activity and anterior tooth grooving in prehistoric California indians.

Abraded grooves have been observed on the anterior teeth of all the adults in a small population of prehistoric California Indians. These dental effects show considerable variety, appearing on maxillary and mandibular teeth, on approximal and occulusal surfaces, and either isolated or bilaterally aligned. Although many of the grooves are indistinguishable from those reported for other prehistoric populations, their variety illustrates the limited applicability of etiological hypotheses previously proposed to account for such effects. It is suggested that the grooves represent traces of a task activity involving the pulling of fibrous materials across the teeth.     

Increase of tooth size in prehistoric coastal Peru, 10,000 B.P.-1,000 B.P.

Teeth increase in size during a 9,000-year period in an archaeologically derived, radiocarbon dated sample of skeletons from a geographically restricted area of coastal Peru. Although cultural change is extensive, including the transition to food production and pottery making, teeth do not reduce as predicted under these conditions by Brace's Probable Mutation Effect. Since most of the dental literature dealing with size change of teeth focuses upon dental reduction, hypotheses explaining why teeth increase through time are not well developed. No obvious selective forces explaining size increase are apparent in the present data. Attrition decreases through time. The increase in tooth size in this collection may be a function of overall cranialfacial size increase, which (pending further data) may be related to a general body size increase.     

Sex estimation based on deciduous and permanent dentition in a contemporary spanish population

Sex estimation of skeletal remains with satisfactory allocation accuracy represents an essential step in reconstructing the biological profile of unknown individuals in archaeological research and forensic practice. Teeth are among the most frequently recovered physical elements of an individual that remain after death due to their hardness, durability, and resistance to postmortem insults. This study was based on the deciduous and permanent dentition of 269 individuals (150 males and 119 females) from the Granada osteological collection of identified infants, young children, and adults (Granada, Spain). Mesiodistal, buccolingual, and diagonal crown and cervical diameters of both dentitions were measured, and logistic regression analyses were performed to create equations for sex discrimination. The results show that the first and second deciduous molars and the permanent canines are the teeth with the greatest sexual dimorphism, providing percentages of correct assignment of sex between 78.1 and 93.1% in deciduous dentition and between 79.4 and 92.6% in permanent teeth, depending on the dimensions used. The results indicate that this method may be applicable as an adjunct with other accepted procedures for sex estimation when fragmentary skeletal remains are encountered in archaeological excavations and in forensic contexts. Am J Phys Anthropol 152:163–164, 2013. © 2013 Wiley Periodicals, Inc.     

The incidence of agenesis and polygenesis in the primate dentition

The incidence of dental agenesis and polygenesis was demonstrated in 978 Old World monkeys, 390 great apes, 194 lesser apes and 5,000 humans of Caucasoid and Negroid stock. The frequency of agenesis was highest in the human sample, particularly in the Negroids, that of polygenesis was highest in the great apes. Within both groups, the polymorphism was commonest in the molar (predominantly third molar) region. Despite numerous difficulties in the interpretation of such data, on the basis of the differences between man, apes and monkeys, it is suggested that the high incidence of agenesis seen in man is a phylogenetic accompaniment of the shortening of the maxillomandibular skeleton, which is such a marked feature of human evolution.     

Tooth size and morphology in a recent Australian Aboriginal population from Broadbeach,South East Queensland

Odontometric and morphologic observations were made of the dentition of skeletal remains of Australian aborigines from Boradbeach, S.E. Queensland. Tooth size, especially of the molars, was found to be significantly larger than that reported for other recent Aboriginal populations. Tooth morphology also differed, with a higher frequency of five cusped second molars, and a lower frequency of shoveling and Carabelli's cusp than previously reported as typical of Australian aborigines.     

Cranial variation in the terminal Late Archaic of Ohio

Cranial and mandibular discrete traits and cranial metric traits were collected from 99-125 individuals in eight terminal Late Archaic sites. The analysis of ten metric traits in six samples showed that the samples shared the same generalized variance and that sexual dimorphism in the means of the metric traits was greater than inter-site differences. Since these samples share the same size and shape expression of a complex set of polygenic traits, we hypothesize a historical relationship among these samples. Discrete trait analysis showed a pattern of differentiation among the eight samples. This pattern of differentiation is related directly to the geographical separation between samples, and, as with metric traits, cultural differences do not contribute to the pattern of biological differences. The overall pattern of osteological variation in these samples can be summarized parsimoniously by paraphrasing the first law of geography: All of the terminal Late Archaic populations of Ohio were related to each other, but closer ones were more related than distant ones.     

Aggregation,interregional interaction,and postmarital residence patterning: A study of biological variation in the late prehistoric middle Ohio Valley

This study examines a perennial problem in anthropology, changes in postmarital residence patterning. Cross‐cultural patterns related to shifts from patrilocal to matrilocal patterns have been attributed to changes in subsistence and/or the result of migrants entering a populated region. Shifts from matrilocal to multilocal patterns have been found to be related to depopulation. This study examines these possibilities in an archeological context through morphometric analyses of human dentition. Comparisons in variability among males and females are made at four Fort Ancient sites in the Middle Ohio Valley that date to sequential time periods between circa A.D. 1000 and 1650. Results show that the earliest site (Turpin) that was occupied during the transition to maize agriculture was patrilocal, whereas two subsequent sites (Anderson and SunWatch) that were occupied after the transition to a maize‐focused diet reflect a matrilocal pattern. The most recently occupied site (Madisonville), occupied during a time of depopulation of the region after a decline in levels of maize consumption and a marked population shuffling contains a multilocal pattern. These results fit well with the various cross‐cultural findings regarding shifts in postmarital residence patterns. Am J Phys Anthropol 154:270–278, 2014. © 2014 Wiley Periodicals, Inc.