Genealogy reconstruction from short tandem repeat genotypes in an Amazonian populationCalafell, Francesc; Shuster, Audrey; Speed, William C.; Kidd, Judith R.; Black, Francis L.; Kidd, Kenneth K.
doi: 10.1002/(SICI)1096-8644(199902)108:2<137::AID-AJPA1>3.0.CO;2-Kpmid: 9988377
We have reconstructed partial genealogies in a sample of 44 SW Amazonian Rondonian Surui, in which 45 dinucleotide short tandem repeat polymorphisms had previously been typed. The genotypes of 488 pairs of individuals having an age difference of 13 or greater were compared, and parentage was excluded if a pair failed to share an allele at more than one locus. In order to test the power of this method, we computed the expected distribution of the number of exclusionary loci for such pairs of unrelated individuals, as well as that for individuals with different degrees of relatedness, and compared it to the observed distribution. We estimated that the pairs compared contained ∼20% of individual pairs with a first‐cousin relation or closer. A total of 25 pairs were identified as possible parent‐child. In three instances, we could identify two or more children having a common parent; we computed a relatedness coefficient in order to establish whether the children were full or half sibs. The genealogies inferred show that instances of polygyny and polyandry (or, alternatively, serial mating), in addition to apparent monogamy, can be found among the Surui. The Surui sample can be used as a model for paleoanthropological populations, in which the determination of relatedness can provide further insights into the social structure of past populations. We estimate that, depending on the history of the populations and the degree of inbreeding, 10–20 highly informative nuclear loci should be typed in order to infer genealogies with acceptable confidence. Am J Phys Anthropol 108:137–146, 1999. © 1998 Wiley‐Liss, Inc.
Population substructure and isolation by distance in three continental regionsEller, Elise
doi: 10.1002/(SICI)1096-8644(199902)108:2<147::AID-AJPA2>3.0.CO;2-Epmid: 9988378
Isolation by distance and divergence from a shared population history are two sources of population substructure. Isolation by distance erases population history as populations approach migration‐drift equilibrium, while diverging populations descended from a single ancestral population will accumulate genetic differences with time. Here I investigate how much of the worldwide genetic diversity from Jorde et al.'s ([1997] Proc. Natl. Acad. Sci. U S A 94:3100–3103) 60 tetranucleotide short tandem repeat (STR) data can be explained by isolation by distance. I use Slatkin's measure of population substructure, RST, principal components analyses, and Mantel tests to investigate the pattern of genetic diversity at both the intercontinental and intracontinental levels. Geographic distance accounts for almost 60% of worldwide interpopulation genetic relationships. Within continents, the correlations are less, although not significantly so because of wide confidence intervals. These results suggest that populations have not reached migration‐drift equilibrium and that there is information in STR data to reconstruct population history.
Body size and physique among Canadians of First Nation and European ancestryKatzmarzyk, Peter T.; Malina, Robert M.
doi: 10.1002/(SICI)1096-8644(199902)108:2<161::AID-AJPA3>3.0.CO;2-Bpmid: 9988379
The purpose of this study was to compare body size and physique among Canadians of Aboriginal (First Nation [FN]) and European ancestry (EA) from the northern Ontario communities of Temagami and Bear Island. The sample consisted of 130 FN and 494 EA participants including adults (20–75 years: 214 men, 234 women) and youth (5–19 years: 97 boys, 79 girls). Indicators of body size and physique included stature, the sitting height–to‐stature ratio (SSR), body mass, BMI, estimated upper‐arm muscle area, biacromial, bicristal, biepicondylar, and bicondylar breadths, and the Heath‐Carter anthropometric somatotype (endomorphy, mesomorphy, and ectomorphy). There were few differences in body size between FN and EA, with the exception of adult females. Adult FN females were significantly heavier and had greater bone breadths than EA women (P < 0.001). On the other hand, somatotype differed significantly between EA and FN by age and sex, except for 5–19‐year‐old females. Among boys and men, FN had greater endomorphy (P < 0.03), whereas FN men also had lower ectomorphy (P < 0.01). Among women, FN were significantly more endomorphic and mesomorphic and less ectomorphic (P < 0.001). Although results for 5–19‐year‐old females were not significant, they were in the same direction as the other groups (greater endomorphy). Forward stepwise discriminant function analyses indicated that endomorphy was the most important discriminator between FN and EA by age and sex. Am J Phys Anthropol 108:161–172, 1999. © 1999 Wiley‐Liss, Inc.
Biological affinities and adaptations of Bronze Age Bactrians: IV. A craniometric investigation of Bactrian originsHemphill, Brian E.
doi: 10.1002/(SICI)1096-8644(199902)108:2<173::AID-AJPA4>3.0.CO;2-3pmid: 9988380
Discovery of a previously unknown Bronze Age civilization (Oxus civilization) centered on the oases of Central Asia revealed the presence of large, preplanned urban centers immediately above sterile soil. Given the absence of local antecedents, the sudden appearance and proliferation of these Oxus civilization urban centers in the oases of Bactria and Margiana immediately raised the issue of where the inhabitants of these urban centers came from. Three hypotheses have been offered by archaeologists to account for the origins of Oxus civilization populations. These include the early influence model, the late colonization model, and the trichotomy model. Eleven craniometric variables from 12 Aeneolithic and Bronze Age samples, encompassing 657 adults from Central Asia, Iran, and the Indus Valley, are compared to test which if any of these hypotheses are supported by the pattern of phenetic affinities possessed by the Oxus civilization inhabitants of the north Bactrian oasis. Craniometric differences between samples are compared with Mahalanobis generalized distance (d2), and patterns of phenetic affinity are assessed with two types of cluster analysis (WPGMA, neighbor‐joining method), multidimensional scaling, and principal coordinates analysis. Results of this analysis provide no support for either the late colonization model or the trichotomy model but do offer some support for the early influence model. Nevertheless, it is clear that the early influence model fails to account for a shift in interregional contacts, perhaps from western China to the north around 2000 bc, that appears to have played a major role in the origins of the Oxus civilization inhabitants of the north Bactrian oasis. Am J Phys Anthropol 108:173–192, 1999. © 1999 Wiley‐Liss, Inc.
Collateral relatives of American Indians among the Bronze Age populations of Siberia?Kozintsev, Alexander G.; Gromov, A.V.; Moiseyev, V.G.
doi: 10.1002/(SICI)1096-8644(199902)108:2<193::AID-AJPA5>3.0.CO;2-Vpmid: 9988381
Nonmetric and metric traits were studied in cranial series representing prehistoric and modern populations of America and Siberia. Frequencies of the infraorbital pattern type II (longitudinal infraorbital suture overlaid by the zygomatic bone) are universally lower in Amerindians than in Siberians. The os japonicum posterior trace, too, is much less frequent in America than in Siberia. The only two Siberian groups with an almost Amerindian combination are late third to early second millennium bc populations from Okunev and Sopka, southern Siberia. The multivariate analysis of five nonmetric facial traits and ten facial measurements in 15 cranial series reveals two independent tendencies. One of them shows a contrast between prehistoric Siberian Caucasoids and modern Siberian Mongoloids; the second one sets Amerindians apart from others. Prehistoric people who lived west of Lake Baikal and modern Uralic speakers are intermediate between Siberian Caucasoids and Siberian Mongoloids; Eskimos, Aleuts, and Chukchi are intermediate between Siberian Mongoloids and Amerindians; and Okunev and Sopka are intermediate between Siberian Caucasoids and Amerindians. Our results suggest that people of Okunev and Sopka are collateral relatives of Amerindians with some Caucasoid admixture. Am J Phys Anthropol 108:193–204, 1999. © 1999 Wiley‐Liss, Inc.
Cranial growth in Homo erectus: how credible are the Ngandong juveniles?Antón, Susan C.
doi: 10.1002/(SICI)1096-8644(199902)108:2<223::AID-AJPA7>3.0.CO;2-8pmid: 9988383
Confusion exists regarding the developmental ages of numerous Asian and southeast Asian Homo erectus fossils because of Weidenreich's contention that Pithecanthropus fused its sutures prematurely relative to H. sapiens. I reevaluate the cranial developmental ages of the Ngandong “juveniles” (2, 5, 8, 9) based on a series of indicators of youth (superstructure development, suture development/fusion, and cranial thickness) and cranial contours. The Ngandong juveniles are compared with H. sapiens adults (n = 281) and subadults (n = 81) and with Ngandong and other H. erectus adults (n = 20) and subadults (n = 4). Cranial contours are assessed using bivariate plots of arc vs. chord measurements. All indicators suggest that Ngandong 5 and 9 are adults, whereas Ngandong 8 is an older juvenile or young adult and Ngandong 2 is a juvenile with a developmental age range of greater than 6 and less than 11 years. In addition, adult cranial contours and the pattern of contour development are similar between Ngandong adults and other H. erectus adults. There is nothing in the cranial contour data to suggest that Ngandong is, despite a relatively large brain, transitional in vault shape between H. erectus and H. sapiens. Am J Phys Anthropol 108:223–236, 1999. © 1999 Wiley‐Liss, Inc.
A new correction procedure for calibrating dental caries frequencyErdal, Yilmaz S.; Duyar, İzzet
doi: 10.1002/(SICI)1096-8644(199902)108:2<237::AID-AJPA8>3.0.CO;2-Zpmid: 9988384
The incisors and canines and the premolars and molars show differential resistance to cariogenic factors. The anterior teeth have a lower caries frequency than the posterior teeth. However, these tooth classes are lost differentially in postmortem stages due to their anatomical structures. This differential postmortem tooth loss distorts proportions between the anterior and posterior tooth classes. The disproportionality can affect the calculation of total caries prevalence. In this paper, we propose a new calibration procedure which removes this disproportionality and call it the proportional correction factor. For this procedure, the caries rates of anterior and posterior teeth are corrected by multiplying the anterior teeth by three‐eighths and the posterior teeth by five‐eighths. These fractions are derived from the human dental formula which contains three anterior and five posterior teeth by side. The correction factor is more effective if the proportion of anterior to the posterior teeth is extremely distorted. When this procedure is used with the caries correction factor, it provides a useful way to approach to an almost true caries prevalence. Am J Phys Anthropol 108:237–240, 1999. © 1999 Wiley‐Liss, Inc.