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Population history and substructure of Anatolia and Turkey as evidenced by craniofacial diversity.
NORIKO SEGUCHI', SERPIL EROGLU2, RYAN W. SCHMIDT ' and C. LORING BRACE 3. 'Department of Anthropology, The University of Montana, Missoula, Department of Anthropology, 2Mustafa Kemal University, Hatay, Turkey, 3Muscum of Anthropology, The University of Michigan, Ann Arbor.
Anatolia, the Asian segment of Turkey, is an area of evolutionary importance for human groups who used this corridor as a bridge for migration between the Caucasus, Western Asia and Europe since Lower Paleolithic times. Historically, Anatolia has been occupied by diverse civilizations, including the Byzantine and Ottoman Empires. This study is an attempt to understand Turkish population substructure and history by examining craniofacial diversity through several temporal periods framed within a population genetic model. if the region of Anatolia has been used as a migratory corridor for peoples spanning disparate geographic areas (Balkans, Central Asia, and East Asia), then gradual craniofacial change is expected due to these migrations coupled with extensive admixture. Studies using mtDNA indicate a pre- Neolithic expansion resulting in extensive migration, while Y chromosome studies reveal haplogroup clustering and gene flow from the Caucus with less admixture from Central and Fast Asia. Overall, our results indicate minimal Turkish population substructure. When crania were separated into sex, our results are consistent with uniparental marker population history. Female crania show a distinctness with modern groups and are actually more similar to Neolithic European and Near Eastern populations. This would indicate a relatively stable female population in Anatolia since Neolithic times. Male crania are more heterogeneous and cluster within a larger geographic zone of Eurasia and the Near East consistent with greater male migration. There is little support for admixture from Central or East Asian groups. These results support the hypothesis for a Turkic language displacement with insignificant genetic exchange.
Modern human origins revisited: Perspectives from Luna Cave (Guangxi, China).
CHRISTOPHER J. NORTON' , WEI WANG' and JENNIE JH JIN3. 'Department of Anthropology, University of Hawaii, Natural History Museum of Guangxi Zhuang Autonomous Region, Nanning, China, 'Department of Anthropology, Pennsylvania State University.
In general, some recent paleoanthropological and genetics studies have argued that the Replacement/Out of Africa 2 hypothesis is the best model to explain modern human origins. Even in East Asia where the evidence supporting the Replacement hypothesis has traditionally been weakest, some studies published in the past decade found support for this model in this region. However, we suggest that the picture in East Asia is more complex than traditionally considered by paleoanthropologists and geneticists, particularly when accounting for the growing number of Late Pleistocene hominin fossils present in the region. In this study, we offer evidence of modern humans that were excavated from stratified deposits in Luna Cave, located in Guangxi Zhuang Autonomous Region, southern China. The primary evidence of modern Homo sapiens from Luna Cave is two teeth (one permanent right lower M2 and one permanent left upper Ml) that morphologically fall within the range of modern Chinese and outside the range ofHomo erectus. The Luna Cave modern human teeth were found in association with speleothems that were uranium-series dated to –70 ka. The data from Luna Cave, along with similar evidence of modern humans from other penecontemporaneous localities throughout southern and central China (e.g., Liujiang, Huanglongdong) suggests that the nature of modern human evolution in East Asia is more complicated than currently viewed. This study was funded by the Wenner-Gren Foundation for Anthropological Research (ICRG 482) and the National Geographic Society (#8372-07).
Genetic structure of Mennonite General Conference, Halderman and Old Colony populations: Molecular perspective.
MICHAEL H. CRAWFORD', PHILLIP E. MELTON', MJ MOSHER', ROHINA RUBICZ' and MARK ZLOJUTRO'. 'Laboratory of Biological Anthropology, University of Kansas, 'Department of Genetics, Southwest Foundation for Biomedical Research, San Antonio.
A study was initiated in 1979 on the genetic structure and biological aging of Mennonite communities of Kansas and Nebraska. Initial analyses based on blood group and protein markers of General Conference Mennonites of Kansas and Nebraska yielded disagreement between the reconstructed history of the congregations and their genetic affinities. Congregations that underwent fission during the early 1900s differed significantly from each other and were suggestive of the action of the founder effect. Additional samples were collected from six communities including Old Order Mennonites, who had emigrated from Cuatemoc, Mexico, and two additional Halderman congregations (Lone Tree and Garden View) that had split off the original community, Meridian. Mitochondrial DNA was extracted from 117 individuals representing six of the congregations and characterized for ten major European RFLP haplogroups. HVS-I sequences were generated using an ABI 370 capillary system sequencer. Eight (H,I,J,K,T,U, pre-V and X) of the ten most common western European haplogroups were observed. SAMOVA analyses, with k number of groups equaling from 2 to 6, provided the most parsimonious k =4 (Fc, =0.07, p-value=0.02). The four groups were: 1) Goessel/Henderson; 2) Meridian/Garden View; 3) Lone Tree; 4) Old Order. Goessel and Henderson constituted a single congregation in the Ukraine until 1860 and split into two communities on relocation to Kansas and Nebraska. Garden View and Lone Tree split from Meridian during the 1970s. MDS plots (stress value = 0.02) reflect the ethnohistory of these populations more accurately than either phylogenetic trees or Rmatrix analyses based on classical genetic markers. This study was funded by grants from: NIH AAGO1646 and Kansas Attorney General Settlement Fund KAN 30471.
Father's education is a crucial predictor of the direction of relationship between the number of children and testosterone levels in Polish men.
GRAZYNA JASIENSKA' and PETER T. ELLISON'. ' Department of Epidemiology and Population Studies, Jagiellonian University, Collegium Medicum, Krakow, Poland, Department of IIuman Evolutionary Biology, Harvard University.
Testosterone (T) levels in males show variation in relation to mating and parenting effort. In human males, both pair-bounding and fatherhood are related to reduced T levels, and experimental parenting stimuli are capable to influence T levels. Our study further explores parenting and T by testing if in fathers number of children was related to their T levels. In Polish men there was a statistically significant relationship between number of children and T levels, however a direction of this relationship was dependent on father's education. In men with below-college education the number of children was positively related to T, both for morning (R' – 0.14, p – 0.005) and evening levels (R' = 0.19, p = 0.0008), while in men with college education the number of children showed a negative relationship with morning (R' – 0.23, p – 0.026) and evening T levels (R' – 0. 21, p – 0.03). We suggest that costs and benefits of having children differ in men depending on their socio-economic status. Differences in such costs and benefits among social classes were especially pronounced in the early years of political and economic transition in post-communist Poland, the period during which our study was conducted..
Sexual dimorphism of sub-cortical structures in the adult human brain using MRI.
PETEA E. JELINEK', KIRK ERICKSON' and STEVEN R. LEIGH'. 'Department of Anthropology, University of Illinois, Urbana- Champaign, 2Department of Psychology, University of Pittsburg.
This study investigates patterns of size variation in sub-cortical structures of the adult human brain to better understand brain size variation between the sexes. Specifically, this research tests a series of research questions concerning relationships between size and shape (scaling relationships) in brains of adult modern humans using in vivo measurements from magnetic resonance imaging (MRI) scans.
Measurements of interest were comprised of total brain volume and 17 sub-cortical regions. Ratios of each of these sub-cortical regions to total brain size were measured. Relative size of these regions was also considered. Subjects include 204 healthy individuals, consisting of two age categories: 51 younger adults, ages 18 to 35, and 153 older adults, ages 50 to 80. MRI's were then segmented in an automated fashion using ESE (FMRIB Software Library).
Non-parametric tests indicate that the hippocampus to total brain size ratio is significantly larger in females, and the amygdala ratio is larger in males but does not approach significance. Results of a linear model indicate the female hippocampus ratio is significantly larger at younger ages. In males, the hippocampus ratio is also larger in the younger group; however, not significantly so. These results indicate the presence of ageregressive changes, particularly in areas related to emotion and memory. Age-based changes in the adult brain may reveal dynamic alterations throughout the course of life. The possible functional significance of these changes is discussed.
When home is the front: A paleopathological study in Medieval Britain.
JAIME JENNINGS. Department of Archaeology, Durham University.
Recent anthropological, historical, and medical studies report that stress caused by living in a region of socio-political conflict is associated with nutritional deficiencies and decreased general health of local residents. The primary objective of this study was to explore health and disease patterns in Medieval (ca. 900 — 1600 AD) populations living along the English and Scottish border; a region which experienced long-term socio-political conflict according to historical documents of the period. Human skeletal remains excavated from cemeteries in the border region were hypothesized to express snore metabolic disease and nutritional indicators of stress than their contemporary neighbors.
Archaeologically excavated skeletons from Medieval cemeteries were macroscopically analyzed using current research standards. Historical documentation states local populations experienced a chronic threat of military occupation or violent assault and probable nutritional depravation throughout the use of the four border cemeteries included in this study. Four cemeteries from neighboring regions which did not experience chronic conflict stress were included as a control group for statistical comparison.
Results show differences only in infection rates between the border populations and their neighbors. Similar metabolic disease and nutritional indicators of stress rates were observed between samples. Without contemporary information provided by the Medieval historical record, the osteological evidence from the Anglo-Scottish border would not indicate local populations experienced great stress. The paleopathological results alone suggest a difference in pathogen load was present in the border populations. This study highlights the need for interdisciplinary approaches to research questions regarding the nature and extent of conflict in the past. Partial funding provided by British Association of Biological Anthropology and Osteoarchaeology and The Rosemary Cramp Fund, Durham University.
Is pelvic dimorphism related to body size dimorphism in humans?
HELEN KURKI. Department of Anthropology, University of Victoria.
Many mammalian species display sexual dimorphism in the pelvis, where females possess larger dimensions of the obstetric canal than males. This is contrary to the general pattern of skeletal size dimorphism, where males are larger than females. This pelvic dimorphism is often attributed to selection relating to parturition, or as a developmental consequence of secondary sexual differentiation. Tague (2005) has argued that among primates, species with higher body size dimorphism have higher pelvic dimorphism (in converse directions) due to the sensitivity to testosterone, rather than specifically obstetric requirements. This study investigates whether this pattern holds in humans by asking: Do human populations with high body size dimorphism, also display high pelvic dimorphism? Previous research demonstrated that in some small-bodied populations, relative pelvic canal size can be larger than in largebodied populations, while others have suggested that larger-bodied human populations display greater body size dimorphism. Climate has also been implicated in human size dimorphism. Nine human skeletal samples (total n: male=144, female=137) were utilized, representing a range of body sizes and geographical regions. Indices of pelvic and body size dimorphism [ln(M/F)] of skeletal dimensions were examined using correlation and least squares regression. The results suggest pelvic dimorphism in humans is generally not correlated with body size dimorphism, although some canal dimensions show a greater magnitude of dimorphism in populations with lower body size dimorphism. Larger samples, more populations, and phylogenetic contrasts could further elucidate these patterns to help us better understand the selective factors that have led to pelvic dimorphism. This research was supported by the Social Sciences and Humanities Research Council of Canada (Grant 9410-2008-2344).
Human sex chromosomes in oral and craniofacial growth.
LASSI ALVESALO. Department of Oral Development and Orthodontics, University of Oulu, Finland, School of Dental Sciences, University of Liverpool, United Kingdom
Determinations of tooth crown sizes and/or the thickness of enamel and dentin have been performed in Finnish Hailuoto population and individuals with sex chromosome anomalies, 45,X, 45,X/46,XX, 46Xi (Xq), 47,XXX, 46, XY females, 47,XYY, 47,XXY males and males with deletion of the Y cluomosome (Kvanttiproject). The results have demonstrated effects on growth of the genes on the human X and Y chromosomes. The Y chromosome promotes growth of both tooth enamel and dentin, whereas the effect of the X chromosome on crown growth seems to be restricted to enamel formation. Enamel growth is decisively influenced by cell secretory function and dentin growth by cell proliferation. The results have also indicated increase in permanent tooth root growth due to the X and Y chromosome effects, and that the various sex chromosomes anomalies are expressed in deviations in e.g. occlusal morphology and cephalometric craniofacial pattern. The location of tooth crown growth promoting gene on the Y chromosome is probably on long arm and on the X chromosome in the short arm. I have suggested that the effect of the Y chromosome is regulatory, at least on amelogenesis, and that especially the effect of the Y chromosome on growth by cell proliferations explain the expression of sexual dimorphism in size, shape and number of the teeth, and under the assumption of genetic pleiotropy, statural growth and sex ratio. It is of great interest that molecular studies have shown that loci for amelogenin, are both the X and Y chromosomes. The Kvantti research project has been supported mainly by the Emil Aaltonen Foundation, the University of Turku Foundation, the Academy of Finland and the Finnish Dental Society.
Ancestry informative SNPs and haplotypes in Native American populations.
KENNETH K. KIDD', JUDITH R. KIDD', FRANCOISE FRIEDLAENDERZ and ANDREW J. PAKSTIS '. ' Department of Genetics, Yale University Medical School, 'Independent Scientist.
A large number of SNPs genotyped on a large number of population samples (including nine Native American (NA) samples), allow comparison of haplotypes and A1Ms in the evaluation of population structure in Native Americans (NA). Our study includes three populations from North America, one from Central America, and five from South America with a total N-425 (data being made public through ALFRED
Both analyses with STRUCTURE at seven clusters assumed show Europeans distinct from Siberians, both distinct from all NA populations, and the NA populations forming five clusters-- three Amazon clusters, two North American clusters, and the remaining four NA populations with partial assignments to five NA clusters. Both analyses show the three Amazonian populations as distinct from each other and all other populations; two west-of-the-Andes and the Central American population form one cluster. With the AIMS the plains Indians emerge as a sixth NA cluster at K=9, the Mexican HapMap sample appears heterogeneous at all K values, and up to K=S, there is partial assignment of the Plains Indians to the Siberian (Khanty and Yakut) cluster. The small set of 128 ATMs is more efficient than 506 unselected haplotypes in these analyses. The AIMS are candidates other research groups could use to allow SNP data on additional NA populations to be pooled for a comprehensive understanding of NA population structure. This study was funded by NIH GM05772 and NSF BCS-0840570.
Correlations between genetic ancestry and superficial traits indicate substantial admixture stratification in Brazil.
LAUREL N. PEARSON, DENISE K. LIBERTON, ELLEN E. QUILLEN, RALITZA L. ZIKATANOVA, RINALDO W. PEREIRA and MARK D. SHRIVER. ' Department of Anthropology, Pennsylvania State University, 'Department of Genomics and Biotechnology, Catholic University of Brasilia.
Brazil is one of the most admixed countries in the world. How this admixture affected the distribution of genetic ancestry across Brazilian ethnic ("Color") groups is a fundamental question which to date has only received minimal attention. In an effort to systematically study variation in genetic ancestry in Brazil, we collected DNA and various phenotypic measures from 596 volunteers in Brasilia, Brazil. Participants were asked to provide their self-described "Color" as defined by the Brazilian census (PretaBlack, PardaBrown, Branca/White, Indigena/Indigenous, Amarela/ Yellow). Phenotype data was collected from each subject including hair texture, highresolution eye photographs, skin and hair color by reflectomehy, and three-dimensional facial photographs. To estimate genomic ancestry, DNA from each participant was genotyped using 176 ancestry informative markers (ATMs), autosomal SNPs with large frequency differences between parental populations known to contribute to Brazilian admixture (West African, East Asian, European and Indigenous American).
Although genomic ancestry shows significant overlap across "Color" groups, there are highly significant differences in average proportional ancestry. Additionally, analyses comparing trait values and genetic ancestry show significant correlations consistent with expectations of populations stratified with respect to genetic ancestry. Ethnographic research indicates that designations of "Color" are fluid and largely based on physical traits as opposed to known ancestry. This likely contributes to the observed ancestry overlap between ethnic groups and the strong association between phenotype and group. This study emphasizes the importance of genetic marker based estimates of ancestry as well as objective assessment of superficial traits in understanding the admixture process.
The role of selection-nominated candidate genes in determining Indigenous American skin pigmentation.
ELLEN E QUILLEN', ABIGAIL W. BIGHAM', RUI MEI' and MARK D. SHRIVER'. 'Dept. of Anthropology, The Pennsylvania State University, Dept. of Pediatrics, University of Washington, 3 Affymetrix, Inc., Santa Clara, California
World-wide variability in skin pigmentation has been a subject of anthropological inquiry from the beginning of our discipline. Recent genomic studies indicate that skin pigmentation is one of the most rapidly evolving phenotypes in many human populations and that genes underlying skin pigmentation have been subject to some of the most extreme selective pressures of any genes in the human genome. Unlike previous research, this study both identifies pigmentation genes that have undergone selection in Indigenous American populations and tests the influences of these genes on skin color in admixed individuals. 906,600 single nucleotide polymorphisms (SNPs) were surveyed for signatures of selection in indigenous populations from Central and South America. Evidence of selection was identified by comparison to HapMap Phase I populations using reduction in heterozygosity (InRH), Locus-Specific Branch Length (LSBL), Tajima's D, and haplotype block structure. In the 12 pigmentation candidate genes that show the strongest evidence of selection (ADAM17, POMC, AP3B1, 0PRM1, SILV, OCA21HERO, PLDN, MYOSA, RAB27A, CYPIA2, ATRN, and ASIP), 48 SNPs selected to represent the overall variation in the selection nominated candidate genes were genotyped in individuals of admixed Indigenous American and European ancestry. These SNPs show substantial allele frequency differences between the parental populations. Using admixture based regression model analyses, genes contributing to darker skin pigmentation in Indigenous Americans were found. This study not only identified skin pigmentation genes contributing to skin color variation in previously understudied Indigenous American populations, it validated the usefulness of using population genetic tests of selection to identify functional genes. This study was generously funded by the National Science Foundation Dissertation Improvement Grant 0925976
Biological affinity of ancient Leptiminus: An analysis of dental morphological traits.
CHERIE K. WALTH. Cultural Resources Project Manager, SWCA Environmental Consultants, Albuquerque.
This study reveals the biological affinity of the Leptiminus people. The use of dental morphological data to determine population affinity provides information on the origins, relationships, migrations, and admixture of these people with other contemporary Mediterranean populations. These studies improve our understanding of the variability of human populations by tracing historical relationships. The dental remains for Leptiminus are from individuals buried in two cemeteries that date from the 2"' to 4" century (A.D. 100- 300). The comparative samples are all from published sources. These samples include one from Carthage, one from Egypt, two from Nubia, five from Italy, and one from the southern Levant, Israel. The use of dental morphological data for population affinity studies provides a means of estimating biological affinity. Frequencies of the dental traits are computed identifying common local and regional occurrences of specific traits. Phenctic similarities are ascertained with the aid of inferential statistical analysis, by comparing the suite of dental traits from the Leptiminus samples with other local and regional populations. The results indicate that the Leptiminus and Carthage samples are phenetically similar supporting the hypothesis of a distinct biological Carthaginian population. Phenetic similarity was shown to exist between one of the Leptiminus samples and a sample from south of Naples, Italy (Campani). This supports the assertion that Italian settlers were installed at Leptiminus as the historical references state. This study was funded by Kelsey Museum at the University of Michigan.
Two-rooted lower canines: A defining characteristic of the Eurodont dentition.
G. RICHARD SCOTT and LINDSAY DORIO. Department of Anthropology, University of Nevada Reno, Reno NV.
With the exception of Carabelli's trait, the European dentition is better known for the morphological traits that it does not exhibit rather than the ones that it does. Europeans show little or no incisor shoveling and double shoveling, incisor winging is rare, accessory cusps of the upper and lower molars are uncommon, as are the protostylid and deflecting wrinkle. Even a major hallmark of the European dentition, 4-cusped lower molars, is defined by the absence rather than the presence of a particular cusp (i.e., the hypoconulid). One root trait, however, runs counter to the characterization of reduced and simplified European crowns and roots. Although a rare trait in general, two-rooted lower canines are far more common in Europeans than in any other regional grouping. In Sub-Saharan Africans, the trait is virtually unknown. In Asian and Asianderived populations, it varies between 0.0 and 1.0 percent. Europeans, by contrast, consistently exhibit frequencies from 5-8% and in a recent study of skeletons from northern Spain, the trait attained a frequency of 10%. Given adequate sample sizes, this trait is extremely useful in evaluating gene flow between Europeans and neighboring groups. In South Siberia for example, a frequency of 3% places these populations almost exactly between Europeans and Asians, a position supported on genetic grounds. In any dental analysis of European skeletal remains, this important variable should be evaluated.
Sequence variation at the TYRPI gene suggests positive selection for darker pigmentation in the African Mandenka population.
HEATHER L. NORTON and MICHAEL F. HAMMER. ARL Division of Biotechnology, University of Arizona.
Variation in levels of melanin, the primary pigment of the skin, can be explained as an evolutionary adaptation to the intensity of ultraviolet radiation (UVR). To assess the potential role of natural selection in shaping patterns of variation at TYRPI, a gene involved in melanin production, we collected 10.7 kb of DNA sequence (including all exons and the 3' and 5' UTR regions) in 154 individuals from three African (Biaka Pygmy, San, and Mandenka) and three non-African (Han Chinese, French Basque, and Melanesian) populations. Only two nonsynoymous mutations were detected, both occurring as singletons, suggesting that coding variation in TYRPI cannot explain maior phenotypic differences between populations. To determine whether patterns of variation across the entire sequenced region were consistent with neutrality, we used a nonparametric test to compare summaries of the frequency spectrum of polymorphism at the TYRPI gene with those from 61 independent non-coding intergenic regions on the autosomes sequenced in the same individuals. Only the Mandenka of Africa showed evidence of a departure from neutrality when compared to these neutral regions (Tajima's D = -1.14, p < 0.05; Fay and Wu's H _ -2.30, p < 0.01). These results are consistent with the hypothesis that a distal regulatory element affecting TYRPI expression levels may contribute to inter-population differences and may have been a target of recent positive directional selection. Although many pigmentation genes have shown evidence of positive selection in low UVR populations, signals of positive selection in high UVR population like the Mandenka are highly unusual. This study was funded by an NIH NIGMS Kirschstein postdoctoral fellowship to HLN (#F32GM080144), a grant from the Wenner Gren Foundation (#7568) to HLN, and a grant from the NSF (BCS-0423670) to MFH.
Genetic diversity of European population isolates in the context of neighboring populations.
JOHN NOVEMBRE', KRISIINA VEERAMA 12, ANKE TON.IES3, PETER KOVACS3 and MICHAEL STUMVOLL3. ' Dept of Ecology and Evolutionary Biology, University of California-Los Angeles, Dept of History and Center for Society and Genetics, University of California-Los Angeles, 3Medical Department, University of Leipzig, Germany.
Recent advances in technologies for surveying single nucleotide polymorphisms (SNPs) at a genome-wide scale provide novel opportunities to study patterns of genetic diversity and gain insights about demographic history. Here we compare genomic-scale SNP patterns of variation in several European population isolates (Adygei, Basque, Orcadian, Roma (gypsies) from Romania, Sardinians, and Sorbs) to geographically proximal non-isolate populations. Our results reveal insights for the demographic history of each of these unique isolate populations, suggesting substantial variation among these population isolates in patterns of diversity and in historical relationships with their neighboring populations. This study was funded by the Mellow Foundation and the Searle Scholars Program.
Ancient Swahili origins: A mitochondrial study of ancient inhabitants of the Kenyan coast.
SLOAN R. WILLIAMS', CHAPURUKiIA M. KUSIMBA2 and KEN BATAI'. 'Department of Anthropology, University of Illinois at Chicago 'Department of Anthropology, The Field Museum, Chicago.
Scholars have long assumed that the ancestors of Swahili peoples were protoBantu who immigrated into the region some three thousand years ago from West Africa. Despite recent studies ofinodern population genetics in East Africa, the population dynamics of the coastal region remains poorly known. We carried out a genetic study on human remains excavated at three coastal sites Mtwapa (ca. 1732 BCE), Tuaca (ca. 800 AD), and Jumba (ca. 1000 ACE). MtDNA was extracted from the wellpreserved teeth of five Swahili samples. Partial HVRI mtDNA sequences were obtained for each sample. The three MtwapamtDNA sequences are early African in origin an d belong to haplogroups L2a, LOf and LIc. The first two haplogroupsare found throughout East Africa in Bantu-, Nilotic- and Cushitic-speaking groups. Both haplogroups are present in modern Taita (L2a=6%, L0f=13%) and Mijikenda (L2a=14%, LOf=2%) who live in the area today. The L I c haplogroup is common in central African Bantu groups and is also found in the Taitaand Mijikenda in tow frequencies (4% and 7% respectively). The Jumba sequence contained transitions at ups 16223 and 16290, placing it in either the LO or L2 haplogroup. The Tuaca sample was poorly preserved, but one sequence fragment contained anp 16189 substitution. The preliminary results show a diverse coastal population that likely included genetic input from nonBantu groups as well. This research was funded by the African Research Council.
Assessing fertility and fecundity in slave groups of the Caribbean from mtDNA sequence variation.
MICHAEL DEASON', VINCENT MACAULAY' and YANNIS PITSILADIS'. 'Integrative and Systems Biology, University of Glasgow, Department of Statistics, University of Glasgow.
The African Diaspora in the Caribbean represents the largest forced relocation in history. While previous works have focused on historic ethnography and modern day molecular demography, few have combined the two. Despite the arrival of roughly 747,500 individuals to Jamaica over 152 years, the final slave population at the cessation of slavery was only 324,000. Slaves were initially acquired from the most westerly point in Sub-Saharan Africa and then progressively along the coast until roughly the Congo Delta. The aim of this study is to assess the matrilineal makeup of modern day Jamaica and compare it to the matrilineal makeup of cited source populations in western Africa in order to glean reproductive success during the era of slavery. Using the first hyper variable region in the mitochondria) genome, 401 Jamaicans were compared to individuals from source populations found in the published literature. Source populations were then divided into West, West-Central, and South Africa. An analysis of molecular variance was then conducted between these groups to assess variation found within and between groups. Results show Jamaica with a greater affinity to West-Central Africa, followed by West and then South. This not only mirrors the historical record as those arriving from West-Central were the most recent, but also highlights the life history constraints present as a result of intensive labor, patriarchal labor assignment, and poor nutrition. Low rates of fertility and fecundity may account for the discrepancy in regional origin. This study was funded by funded by internal funds from University of Glasgow.
Explaining patterns of human genetic variation using coalescent-based models of human origins.
MICHAEL DEGIORGIO', MATTIAS JAKOBSSON', JAMES H DEGNAN' and NOAH A ROSENBERG ' '1,5 Center for Computational Medicine and Bioinformatics, University of Michigan, Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Norbyagen 18D, Uppsala, Sweden, 3 Department of Mathematics and Statistics, University of Canterbury, New Zealand. °Department of Human Genetics, University of Michigan,'Life Sciences Institute, University of Michigan.
Studies of worldwide human variation have discovered three trends in summary statistics as a function of increasing geographic distance from East Africa: a decrease in heterozygosity, an increase in linkage disequlibrium (LD), and a decrease in the slope of the ancestral allele frequency spectrum. To explain these trends, we develop a coalescent-based serial founder model of human origins, in which populations migrate outward from Africa through a process where each of a series of populations is formed from a subset of the previous population in the outward expansion. Our model both recovers the observed decline in heterozygosity with increasing distance from Africa and produces the patterns observed in LD and the ancestral allele frequency spectrum. Although migration between neighboring populations and limited admixture between modern and archaic humans can be accommodated in the model while continuing to explain the three trends, a competing model in which a wave of outward modern human migration expands into a series of preexisting archaic populations produces nearly opposite patterns to those observed in the data. The results support a primary influence on variation patterns of a cumulative effect of genetic drift as humans colonized the world, and they highlight the utility of coalescent-based evolutionary models in providing explanations for observed patterns of human genetic variation.
Mobility evidence during the Bell Beaker period in Western Switzerland through strontium isotope study.
JOCELYNE DESIDERI', DOUGLAS PRICE, JAMES BURTON', PAUL FULLAGAR and MARIE BESSE' . ' Department of Anthropology and Ecology, University of Geneva, Department of Anthropology, University of Wisconsin, 'Department ofGeological Sciences, University of North Carolina.
The Bell Beaker culture initially refers to a pottery style largely widespread during the third millennium BC. Its particularly large geographic distribution has provoked different interpretations: diffusion of a culture by population movement, long-distance exchange of prestige goods, and absence of a real Bell Beaker population with only the diffusion of its cultural components.
In Switzerland, the Bell Beaker period would have developed following influences varying from both the Mediterranean region and Central Europe. Our previous research on dental morphology (nonmetrics) clearly shows a variability of the end of the Neolithic populations (Final Neolithic and Bell Beaker periods) which probably reveals mobility or external population contribution in Western Switzerland.
In order to validate and quantify this external population contribution during the Bell Beaker period in this region, enamel of 23 Bell Beaker individuals from the necropolis of the Petit- Chasseur (Sion, Valais, Switzerland) have been analyzed for strontium isotope ratio ("Sr/86Sr). Results of strontium isotope ratio are concordant with dental morphology results supporting mobility during the Bell Beaker period in Western Switzerland. Moreover, these results reveal some interesting points about the Bell Beaker individuals who have changed their "geological" residence during their lifetimes. This study was funded by the Swiss National Foundation (FNS), grant number IZKOZ3- 123828/1 and the Boninchi Foundation (Geneva, Switzerland).
A synthetic view of morphological and genetic diversity in the Americas.
ROLANDO GONZALEZ-JOSE', MARIA. C. BORTOLIN12, FABRICIO. R. SANTOS' and SANDRO. L. BONATTO4. ' Centro Nacional Patag6nico, CONICET, Argentina, 'Departamento de Gen6tica, Universidade Federal do Rio Grande do Sul, Brazil, 'Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Brazil, 4Faculdade de Biociencias, Pontificia Universidade Cat6lica do Rio Grande do Sul, Brazil.
During the last decades, several studies based mainly on partial evidence such as skull morphology, archaeology, linguistics and molecular genetics have presented competing, apparently mutually exclusive, settlement hypotheses. In general terms, the main contradictory views are represented by the genetic-based "Single Wave" or "Out of Beringia" model and the cranial morphologybased "Two Components/Stocks" model. Here, we present a geometric morphometric analysis of 576 ancient and modern skulls suggesting that the classical "Paleoamerican" and "Mongoloid" craniofacial patterns should be viewed as extremes of a continuous morphological variation. We discuss our results in the light of recent advances aimed to detect the stochastic or non-stochastic (e.g. selective) origin of the observed morphological patterns. Our results suggest that recent contact among Asian and American circumarctic populations took place during the Holocene. These results along with data from other fields are synthesized in a model for the settlement of the New World that considers, in an integrative and parsimonious way, evidence coming from genetics and physical anthropology. This model takes into account a founder population occupying Beringia during the last glaciation characterized by high craniofacial diversity, founder mtDNA and Y-chromosome lineages, and some private autosomal alleles. After a Beringian population expansion, which could have occurred concomitant with their entry into America, more recent circumarctic gene flow would have enabled the dispersion of northeast Asian-derived characters and some particular genetic lineages from East Asia to America and vice versa.
Chuvash origins: Evidence from mtDNA Markers.
ORION M. GRAF T, JOHN MITCHELL 2, STEPHEN WILCOX', GREGORY LIVSHITS°, MICHAEL H. CRAWFORD'. 'Department of Anthropology, Lab of Biological Anthropology, University of Kansas, Dept of Genetics, School of Molecular Sciences, La Trobe University, Melbourne. 'Australian Genome Research Facility Ltd, The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia, 'Department of Anatomy, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
A sample of 96 unrelated individuals from Chuvashia, Russia was sequenced for hypervariable region-I (HVR-I) of the mtDNA molecule. The Chuvash speak a Turkic language that is not mutually intelligible to other extant Turkish groups, and their genetics are distinct from Turkic-speaking Altaic groups. Some scholars have suggested that they are remnants of the Golden Horde, while others have advocated that they are the products of admixture between Turkic and Finno-Ugric speakers who came into contact during the 13d' century. Earlier genetic research using autosomal DNA markers suggested a Finno- Ugric origin for the Chuvash. This study examines non-recombining DNA markers to better elucidate their origins.
The majority of individuals in this sample exhibit haplogroups H (31%), U (22%), and K (11 %), all representative of western and northern Europeans, but absent in Altaic or Mongolian populations. Multidimensional scaling (MDS) was used to examine distances between the Chuvash and 8 reference populations compiled from the literature. Mismatch analysis showed a unimodal distribution. Along with neutrality tests (Tajima's D (1.43365) p<0.05, Fu's Fs 25.50518) p<0.001), the mismatch distribution is suggestive of an expanding population. These tests suggest that the Chuvash are not related to the Altai and Mongolia along their maternal line but supports the "Elite" hypothesis that their language was imposed by a conquering group-- leaving Chuvash mtDNA largely of Eurasian origin with a small amount of Central Asian gene flow. Their maternal markers appear to most closely resemble Finno-Ugric speakers rather than fellow Turkic speakers.
A cross-cultural perspective on human-pet dynamics.
PETER B. GRAY and SHARON M. YOUNG. Department of Anthropology, University of Nevada, Las Vegas.
Due in part to declining human fertility, geographic mobility, and growing consumerism, pets increasingly serve the function as emotional surrogates of children, with tremendous resources poured into their care. However, this function of pets may be quite different from the more typical human-pet dynamics characterizing a wider array of societies until recently. To help fill a gap in scholarship on pets, we sought to better characterize human-pet dynamics in a standardized cross-cultural sample. Using the electronic Human Relations Area 60 society Probability Sample (eHRAF), we coded for various features of human-pet dynamics. Preliminary analyses indicate that dogs are the most commonly kept pets, with other pets including cats, birds, primates, and turtles. We also present data on pet socioecological functions (e.g., hunting, protection, playthings for children), living arrangements, diet, and both positive (e.g., grooming, verbal communication, perceptions) and negative (e.g., killing, physical abuse, verbal abuse) facets of human-pet interactions. As one example of a positive human-pet interaction, in five societies humans are described breastfeeding pets such as dogs and nonhuman primates. These data illustrate both similarities and differences cross-culturally in human-pet dynamics as well as many stark contrasts with how pets such as dogs in the U.S. are treated today in contrast to patterns from this wider sample.
Ancient DNA insights into American colonization.
DENNIS H. O'ROURKE', JUSTIN TACKNEY' and JENNIFER RAFF' . 'Department of Anthropology, University of Utah, Salt Lake City.
Ancient DNA studies of the colonization of the Western Hemisphere have been limited, although the potential for novel insights is great. Despite methodological advances, diversity at the single mitochondrial locus remains the focus. aDNA results indicate that although the primary American mtDNA haplogroups were present at founding, and had achieved substantial geographic structure prior to 3,000 years ago, genetic drift has resulted in some loss of haplotype diversity. Simulations, indicate that these drift effects need not have been associated with drastic population reduction or exceptionally small founding populations. As more full-sequence data become available, aDNA studies will provide more precise estimates of coalescent ages for multiple genetic lineages, enabling 1) direct comparisons of genetic and archaeological dates for prehistoric events, 2) more accurate estimates of demographic parameters (e.g., effective size) for modeling alternative colonization models, and 3) more robust testing of the effects of evolutionary forces on the structuring of modern genetic variation. Assessing the extent and pattern of prehistoric genetic variation relative to morphological variation will require greater access to nuclear genetic data in ancient samples than is currently routinely pursued. Expanding aDNA sampling to include archaeo-faunal collections, as well as the genomes of ancient human pathogens, will help to further clarify prehistoric population dynamics. More substantive contributions from aDNA studies will require larger and older ancient samples (>10,000 BP), especially from South America, areas of Beringia, and intervening coastal regions. This argues for greater coordination between geneticists and archaeologists to accumulate maximally informative samples for aDNA analyses.
Evaluating ancestry based on craniometrics. A comparative study between Fordisc 3.0 and CRANID6 using crania from St. Leonard's Church, Hythe.
IIANNAII BUTTERFIELD ' and MARIE LOUISE JORKOV2". University of Bournemouth, ' Copenhagen City Museum, 3 Laboratory of Biological Anthropology, Copenhagen University.
The ossuary at St. Leonard's Church in Hythe, England contains approximately 2000 crania dating back to the 14th and 15th centuries, however, little is known of their origin. The initiation of establishing a biological profile for the individual crania (n = 40) has been undertaken using the statistical computer programmes CRANID6 and Fordisc 3.0. Utilising Discriminant Function Analysis (DFA) CRANID6 and Fordisc 3.0 determine the likely ancestry of an unknown crania based on known population samples. CRANID6 is based upon population data obtained by Howells and Wright and Fordisc 3.0 provides DFA using Howells population data and a separate analysis using data from the University of Tennessee Forensic Data Bank. The results obtained from the DFA using CRANID6 and Fordisc 3.0 were found to be significantly different using the chi square test (p = < 0.05). CRANID6 found 80% of the Hythe sample to be most similar to individuals of Caucasoid ancestry; however Fordisc 3.0 resulted in only 50-67% of the Hythe sample being categorised as having Caucasoid ancestry. Further statistical analysis undertaken on Howells' European population samples found the Hythe sample to closely resemble crania from Zalavar, Hungary. It can be concluded that in the analysis of a possible European cranial sample, Fordisc 3.0 should not be used, due to the lack of European population samples. CRANID6 is the most appropriate DFA program to use. However it should be used with caution and combined with anthroposcopic analysis.
ABO blood group frequencies in a pre - Columbian Native American population from California.
FERNANDO A. VILLANEA', CARA MONROE' '' ', ALAN LEVENfHAL4, ROSEMARY CAMBRA' and BRIAN M. KEMP'J. ' Department of Anthropology, Washington State University, Department of Anthropology, University of California, Santa Barbara, 3School of Biological Science, Washington State University, 'Departments of Anthropology and Urban Planning, San Jose State University, 'Chairwoman, Muwekma Ohlone Tribe.
Almost all Native Americans belong to either the O t or Ot, blood group, with regards to the ABO blood group system. Some have suggested that the reduction of the otherwise common A alleles among Native Americas may have resulted from major selective pressure following the introduction of infectious disease, such as smallpox, into the Americas by Europeans. However, the reduced diversity at the ABO locus may well predate the contact period, as it is believed that Native American populations derive from a relatively small Beringian founder population prior to migrating to the Americas. Thus it is probable that the bottleneck associated with this event (-15,000 years ago) decreased their heterozygosity at the ABO blood group locus. While previous studies have used ancient DNA analyses to determine if precontact populations also lack A blood groups, their sample sizes have been small and from scattered sites. In this study we analyze ancient DNA from an ancestral Muwekma Ohlone burial site in the San Francisco Bay Area in California that dates to approximately 1,500-2,000 years ago. CA-SCL-38 contains 210 burials, a more complete precontact Native American population that allows to demonstrate the high frequencies O l and Ot, blood groups today is unlikely to be the outcome of population decline following European contact.
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