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C G Turner

Publications and source records attributed to C G Turner.

At least 19 recordsLinked to original sources
PubMed1990

Major features of Sundadonty and Sinodonty, including suggestions about East Asian microevolution, population history, and late Pleistocene relationships with Australian aboriginals.

The eight diagnostic morphological traits of the Sundadont and Sinodont divisions of the Mongoloid dental complex are identified. Intra- and intergroup variation for these crown and root features is plotted. The univariate frequency distributions provide useful evidence for several suggestions about East Asian prehistory, dental microevolution, and intergroup relationships. The case for local evolution of Sundadonty is strengthened by finding Australian teeth to be very similar to this pattern. Australian Aboriginal teeth are also generally like those of Jomonese and some Ainus, suggesting that members of the late Pleistocene Sundaland population could have initially colonized Sahulland as well as the continental shelf of East Asia northward to Hokkaido.

Asian People↗
PubMed1989

Morphological and metrical comparison of San and Central Sotho dentitions from southern Africa.

Comparative morphological and metrical study of San and Central Sotho dentitions indicates that the teeth of the two samples are significantly different from one another. The San dental complex contains traits that add mass to the occlusal surface of microdontic dentitions: moderate low-grade UI1 (13.5%) and UI2 shoveling (24.7%), high Bushman canine (43.1%), fairly low UM2 hypocone reduction (23.3%), high UM2 cusp 5 (55.6%), high LM1 cusp 7 (35.2%), LM1 distal trigonid crest (7.1%), and LM2 deflecting wrinkle (5.3%), lack of reduction of LM1 and LM2 cusp number, in the presence of very low UM1 Carabelli's trait (6.7%) and high LM2 Y-groove (86.3%). Culturally, males occasionally exhibit filed UI1 and females are missing LI1. Conversely, mesodontic Central Sotho dentitions display a more simplified morphology, with the exception of moderately high incidence of UM1 Carabelli's trait (41.0%) and very high LM1 cusp 7 (71.3%). Discriminant analysis of mesiodistal and buccolingual diameters and tooth crown surface area data for the left maxillary teeth supports classification of San dentitions as microdont and Central Sotho dentitions as mesodont. Additionally, metrical analysis indicates that San teeth are more sexually dimorphic than are those of Central Sotho.

Adolescent↗
PubMed1989

Human skeletal and dental remains from Lapita sites (1600-500 B.C.) in the Mussau Islands, Melanesia.

The Lapita Cultural Complex, radiometrically dated to between 3,600 and 2,500 B.P., is regarded on archaeological evidence as ancestral to modern Austronesian-speaking cultures of eastern Melanesia and Polynesia. To date, there has been a lack of human skeletal and dental material from Lapita sites; thus, the present sample from Mussau Island, although small, offers an opportunity to present some preliminary observations of their importance to Oceanic prehistory. The present analysis, based mainly on teeth, suggests that the Mussau Island Lapita people had slightly closer affinities with Indonesian than with Melanesian populations. These results correspond well with linguistic and archaeological evidence regarding the origin of the Lapita Cultural Complex.

Age Factors↗
PubMed1989

Teeth and prehistory in Asia.

Where did the peoples of East Asia, Polynesia and the Americas originate? Teeth tell the story. Analysis of minute dental features shows that two great population groups formed in southeast Asia beginning more than 20,000 years ago. The movement of one group can be traced across the Bering land bridge into North America and all the way to Chile.

Emigration and Immigration↗
PubMed1987

More lingual surface attrition of the maxillary anterior teeth in American Indians: prehistoric Panamanians.

Lingual surface attrition of the maxillary anterior teeth (LSA-MAT) has been found in additional prehistoric Latin American Indian skeletons. LSAMAT was first observed in crania from an Archaic Brazilian site. This second finding occurs in teeth from Venado Beach, a late prehistoric site in Panama. LSAMAT is also present in some fragmentary specimens from the Archaic Cerro Mangote site in Panama. LSAMAT at Venado Beach is present in 57% of 28 adult crania. As in the Brazilian study, LSAMAT is associated with a high caries rate (82% of 50 adults; 11.7% of 852 permanent teeth). As first suggested, eating and processing of some type of abrasive carbohydrate food, such as manioc, is the possible cause of LSAMAT. However, other possible causes relating to habitation on or near marine coasts cannot be totally ruled out.

Cuspid↗
PubMed1987

Late Pleistocene and Holocene population history of East Asia based on dental variation.

The purpose of this communication is to provide a summary description and analysis of 28 dental traits studied in a number of skeletal samples that originated in eastern Asia. The objectives of the analysis are to define the nature of Mongoloid dental variation, use it to measure Asian intergroup relationships, and develop in greater detail and with larger samples a dental anthropological model of the late Pleistocene and Holocene population history of eastern Asia.

Asia↗
PubMed1986

Intra- and interobserver concordance in classifying dental morphology.

A sample of 50 Kodiak Island Eskimo dental casts were observed, using standard reference plaques, three times by one observer and once by a second observer, for 47 graded and discrete morphological characters of the dentition and jaws. Although the frequency of both intra- and interobserver scoring differences between observation sessions are relatively high for some characters, statistical analysis reveals that differences are largely random in direction and cancel out. Most dental morphological variants can be observed in a ranked fashion with adequate within- and between-observer reliability. However, four traits present both within- and between-observer difficulties: the tuberculum dentale, the canine distal accessory ridge, marginal accessory cusps of the upper first premolar, and the anterior fovea on the lower first molar.

Alaska↗
PubMed1985

Expression count: a method for calculating morphological dental trait frequencies by using adjustable weighting coefficients with standard ranked scales.

Expression count is the term used for a new method of calculating the frequency of a morphological dental trait in a population sample. This method incorporates into a single value the total trait variation expressed in the sample. It has been designed to increase the information content of small samples of dental remains common with archeological recovery.

Biometry↗
PubMed1984

Variation in the convexity of the human maxillary incisor labial surface.

Labial surface convexity of the maxillary central incisors ( ILC ) is classified with a new five grade ranked scale. More than 2,000 individuals representing 20 worldwide populations were studied. Principle findings are 1) sexual dimorphism is not significant, 2) antimere asymmetry is moderate, 3) labial convexity is negatively associated (r = -0.48) with labial surface double- shovelling , and 4) significant differences occur between several populations. Convexity is most marked in African and Asiatic Indian populations, particularly Bushmen . Europeans have intermediate degrees of convexity, and American Indians the least; Eskimos have the highest amount of convexity among Native Americans. Pacific Islanders are intermediate; Melanesians show the strongest expression of incisor labial convexity in the Pacific.

Anthropometry↗
PubMed1984

Advances in the dental search for Native American origins.

The Sinodont dental morphology pattern of NE Asia is today more complex and was so by 20,000 years ago, than the simplified Sundadonty of SE Asia-Oceania, and the very simplified pattern that evolved greater than 20,000 B.P. All Native Americans are Sinodonts. Intra--and inter-hemispheric statistical analyses of 28 dental traits in greater than 6000 N & S American and greater than 1100 NE Asian crania reveal three temporally stable American sub-patterns, suggesting prior evolution in Sino-Siberia. The hypothesized biocultural associations and migration episodes are: (1) "Upper Cave" Sinodonts with the generalized Chinese Microlithic Tradition reach the Arctic steppe via the Lena basin to become Paleo--and most later Indians. (2) Smaller-game-hunting Siberian Diuktaians cross to Alaska at forest-forming terminal land bridge times to become Paleo-Arctic and subsequent Na-Dene-speaking NW forest Indians. (3) Lower Amur basin-N Japan blade-makingfolk evolve a coastal culture on the way to the land bridge's SE terminus at Anangula-Umnak where the oldest skeletons of the dentally distinctive but variable Aleut-Eskimos have been found.

Americas↗
PubMed1981

Dentition of Chilean paleo-Indians and peopling of the Americas.

Teeth of 12 cremated paleo-Indians (11,000 years old) from caves in southern Chile have crown and root morphology like that of recent American Indians and north Asians, but unlike that of Europeans. This finding supports the view that American Indians originated in northeast Asia. This dental series also suggests that paleo-Indians could easily have been ancestral to most living Indians, that very little dental evolution has occurred, and that the founding paleo-Indian population was small, genetically homogeneous, and arrived late in the Pleistocene.

Aged↗
PubMed1981

Root number determination in maxillary first premolars for modern human populations.

It is suggested that multiple root number of the maxillary first premolar be defined on the basis of lingual and buccal-root bifurcation greater than one-fourth to one-third (25%--33%) the buccal-root length. This meets pragmatic considerations and would enhance comparability of between-observer findings for an apparently independent trait of potential importance for population characterization, forensic identification, and microevolutionary analysis.

Bicuspid↗
PubMed1978

The dentition of New Britain West Nakanai Melanesians. VIII. Peopling of the Pacific.

The dental crown morphology and size of 48 male West Nakanai, New Britain, Melanesians is described and compared with other Pacific and Asian dental samples. The West Nakanai dentition is like those of other Melanesians, much less like those of Polynesians and Micronesians, and very dissimilar to teeth of modern and Neolithic Southeast Asians. It is suggested that the origin of the modern Melanesian dental pattern (large but simplified teeth) was probably in Melanesia, not Southeast Asia as the orthodox view of a Hoabinhian-Australmelanesian relation claims.

Asian People↗
PubMed1977

Additional features of Ainu dentition. V. Peopling of the pacific.

Crown morphology of 85 plaster dental casts from skeletal and living Ainus of less than 1/8 non-Ainu admixture is described and compared for microevolutionary and origins considerations. There is no significant sex dimorphism and few inter-sample differences through time. Inter-observer differences occur where observation standards are poorly established. Ainu teeth exhibit a simplified pattern and have trait frequencies more like those of Polynesians and Micronesians than like Chinese, Japanese or Europeans. There is no dental evidence in support of a Caucasoid origin or close relationship. Similarities outnumber differences between Ainu teeth and those of Micronesians and Polynesians suggestive of a past biological relationship.

Adolescent↗
PubMed1976

The etiology and porotic hyperostosis among the prehistoric and historic Anasazi Indians of Southwestern United States.

Porotic hyperostosis was studied in 539 crania from maize-growing prehistoric and historic groups who occupied two dissimilar ecological zones of the Plateau country of Arizona and New Mexico--canyon bottoms and sage plain. Defined as abnormal localized sieve-like structural changes involving the hematopoietic areas of the cranium, it was found in 185 (34.3%) of these skulls. More frequent in children than in adults, it shows significant frequency differences between both children and adults of the two ecological zones. The two ecological zones differ in the availability of iron in the diet; the canyon inhabitants depended heavily on maize (which interferes with iron absorption) while the sage plain people consumed more iron-rich animal products. We hypothesize that an increased dependence on maize produced more iron deficiency anemia and resulted in more porotic hyperostosis. Maize is known to have permitted a food surplus which in turn allowed for increased Southwestern population growth in marginal areas like the canyon bottoms. Heavy dependency on a single food type with consequent hematologic problems may have been an important reason for the subsequent abandonment of the Anasazi region.

Adult↗