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American Groups (american + groups)
Selected AbstractsSexual Dimorphism in America: Geometric Morphometric Analysis of the Craniofacial Region,JOURNAL OF FORENSIC SCIENCES, Issue 1 2008Erin H. Kimmerle Ph.D. Abstract:, One of the four pillars of the anthropological protocol is the estimation of sex. The protocol generally consists of linear metric analysis or visually assessing individual skeletal traits on the skull and pelvis based on an ordinal scale of 1,5, ranging from very masculine to very feminine. The morphologic traits are then some how averaged by the investigator to estimate sex. Some skulls may be misclassified because of apparent morphologic features that appear more or less robust due to size differences among individuals. The question of misclassification may be further exemplified in light of comparisons across populations that may differ not only in cranial robusticity but also in stature and general physique. The purpose of this study is to further examine the effect of size and sex on craniofacial shape among American populations to better understand the allometric foundation of skeletal traits currently used for sex estimation. Three-dimensional coordinates of 16 standard craniofacial landmarks were collected using a Microscribe-3DX digitizer. Data were collected for 118 American White and Black males and females from the W.M. Bass Donated Collection and the Forensic Data Bank. The MANCOVA procedure tested shape differences as a function of sex and size. Sex had a significant influence on shape for both American Whites (F = 2.90; d.f. = 19, 39; p > F = 0.0024) and Blacks (F = 2.81; d.f. = 19, 37; p > F = 0.0035), whereas size did not have a significant influence on shape in either Whites (F = 1.69; d.f. = 19, 39; p > F = 0.08) or Blacks (F = 1.09; d.f. = 19, 37; p > F = 0.40). Therefore, for each sex, individuals of various sizes were statistically the same shape. In other words, while significant differences were present between the size of males and females (males on average were larger), there was no size effect beyond that accounted for by sex differences in size. Moreover, the consistency between American groups is interesting as it suggests that population differences in sexual dimorphism may result more from human variation in size than allometric variation in craniofacial morphology. [source] The biosynthesis of Juvenile Hormone, its degradation and titres in females of the true armyworm: a comparison of migratory and non-migratory populationsPHYSIOLOGICAL ENTOMOLOGY, Issue 2 2000Jeremy N. McNeil Summary In a previous study [McNeil et al. (1996) Archives of Insect Biochemistry and Physiology, 32, 575,584], patterns of sexual maturation and Juvenile Hormone (JH) biosynthesis were compared in virgin females from migratory (North American) and non-migratory (Azorean) populations of the true armyworm moth, Pseudaletia unipuncta Haworth (Lepidoptera: Noctuidae). Sexual maturation occurred at a significantly earlier age after emergence in the non-migrant population, and the rates of biosynthesis of JH in vitro suggested that lower titres of JH may be required to initiate the onset of calling behaviour (pheromone emission) and ovarian development in Azorean females. To examine the physiological differences in the reproductive biology of migratory and non-migratory populations in greater detail, the haemolymph titres of JH and JH esterase activity were compared in virgin females as a function of age. In addition, the effects of mating on JH biosynthesis in vitro, JH titres, JH esterase activity and egg production were measured in the two populations. As expected, JH titres rose more rapidly after emergence in Azorean females than in their North American counterparts but, contrary to our prediction, the maximum levels were also higher in the non-migrant population. Activity of JH esterase was much higher in Azorean females on the day of emergence. However, by the second day both populations had similar activity levels (about 17 nmol JH/min/ml) and exhibited a similar age-related decline in subsequent days. Mating did not affect the rate of JH biosynthesis in vitro but resulted in a significant increase in the titres of JH in the haemolymph of both populations. The maximum titre (a five-fold increase) occurred within 24 h of mating in Azorean females. In North American individuals the increase was greater (seven-fold) but did not occur until 48 h after mating. No difference in the activity of JH esterase was observed between mated and virgin North American females. By contrast, while there was an age-related decline in the activity of JH esterase in mated Azorean females, as seen in both North American groups, activity levels in virgin females remained constant with age. In all females, mating resulted in a significant increase in egg production within 24 h. The Azores is a volcanic archipelago, so these non-migratory populations were probably founded by immigrants originating from migratory continental populations. It is clear from our results that the change from a life history that includes migration to a non-migratory one involved more than just a temporal shift in the timing of the production of JH. Furthermore, the interpopulation differences in titres of JH and mating-induced changes reported here cannot be fully explained by the observed differences in the patterns of activity of JH esterase and JH biosynthesis in vitro. [source] Blood group O alleles in Native Americans: Implications in the peopling of the AmericasAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Benito Estrada-Mena Abstract All major ABO blood alleles are found in most populations worldwide, whereas the majority of Native Americans are nearly exclusively in the O group. O allele molecular characterization could aid in elucidating the possible causes of group O predominance in Native American populations. In this work, we studied exon 6 and 7 sequence diversity in 180 O blood group individuals from four different Mesoamerican populations. Additionally, a comparative analysis of genetic diversity and population structure including South American populations was performed. Results revealed no significant differences among Mesoamerican and South American groups, but showed significant differences within population groups attributable to previously detected differences in genetic drift and founder effects throughout the American continent. Interestingly, in all American populations, the same set of haplotypes O1, O1v, and O1v(G542A) was present, suggesting the following: (1) that they constitute the main genetic pool of the founding population of the Americas and (2) that they derive from the same ancestral source, partially supporting the single founding population hypothesis. In addition, the consistent and restricted presence of the G542A mutation in Native Americans compared to worldwide populations allows it to be employed as an Ancestry informative marker (AIM). Present knowledge of the peopling of the Americas allows the prediction of the way in which the G542A mutation could have emerged in Beringia, probably during the differentiation process of Asian lineages that gave rise to the founding population of the continent. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Federal Repatriation Legislation and the Role of Physical Anthropology in RepatriationAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue S41 2005Stephen D. Ousley Abstract Two laws governing the disposition of Native American human remains in museums and institutions have had a profound impact on anthropology, and especially physical anthropology. In contrast to the perception of constant conflict between Native Americans and physical anthropologists, the repatriation process based on these laws has been in large part harmonious between institutions and Native peoples in the US. Despite misconceptions, the Native American Graves Protection and Repatriation Act (NAPGRA; 25 United States Code (U.S.C.) 3001-3013) was not intended to halt further research on Native American remains in museums. In fact, court decisions have affirmed that the documentation of human remains produces information no other methods can provide, and provides necessary evidence to be incorporated and weighed, along with other evidence, in evaluating "cultural affiliation," the legal term for the required connection from federally recognized Native American groups to their ancestors. The wide variety of osteological data collected at the National Museum of Natural History (NMNH), Smithsonian Institution, have proven indispensable when evaluating cultural affiliation, especially when other information sources are unhelpful or ambiguous, and provide an empirical basis for determining the ancestry of individuals whose remains will be discovered in the future. To date, the claim-driven process at the NMNH has resulted in the affiliation and repatriation of more Native American remains than any other institution in the country. Repatriation experiences at the NMNH demonstrate the changing relationships between museums and Native peoples, the continuing important contributions that physical anthropology makes to the repatriation process, and the importance of physical anthropology in understanding the recent and ancient history of North America. Yrbk Phys Anthropol 48:2,32, 2005. © 2005 Wiley-Liss, Inc. [source] Spanish colonial effects on Native American mating structure and genetic variability in northern and central Florida: Evidence from Apalachee and western TimucuaAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2005Christopher M. Stojanowski Abstract Standard population genetic analyses are implemented for a series of precontact and contact period samples from central and northern Florida to investigate changes in genetic variability and population affinity coincident with the establishment of Spanish missions during the 17th century. Estimates of FST based on odontometric data indicate limited heterogeneity for the Apalachee samples, suggestive of some degree of within-group endogamy for this ethnic group prior to contact. This corresponds well with ethnohistoric reconstructions indicating that Apalachee were populous, partially linguistically isolated from its neighbors, and involved in persistent cycles of warfare with neighboring groups. Estimates of extralocal gene flow for the Apalachee samples indicate limited initial changes in the mating structure of these populations. After 1650, however, extralocal gene flow increases, consistent with evidence for dramatic population movements throughout northern Florida and increased Spanish presence in the province, particularly at the mission of San Luis. Inclusion of non-Apalachee outgroups does not increase estimates of genetic heterogeneity, as was expected based on ethnohistoric data. The pattern of genetic distances suggests a biological division between north and south Florida population groups, consistent with archaeological and ethnohistoric data, and similarly indicates some distinction between precontact and postcontact local groups. Differential extralocal gene flow experienced by pre-1650 Apalachee and Timucua populations suggests localized mission experience. The Apalachee, with large, dense populations, experienced limited initial changes in genetic diversity or mating structure. However, after 1650 they were apparently involved in a much more expansive mating network that may have included Spaniards and immigrant Native American groups to the region. These results are in contrast to the mission experience of the Guale Indians of the Georgia coast. Am J Phys Anthropol, 2005. © 2005 Wiley-Liss, Inc. [source] Population Genomics and Research Ethics with Socially Identifable GroupsTHE JOURNAL OF LAW, MEDICINE & ETHICS, Issue 3 2007Joan L. McGregor In this paper, the author questions whether the research ethics guidelines and procedures are robust enough to protect groups when conducting genetics research with socially identifiable populations, particularly with Native American groups. The author argues for a change in the federal guidelines in substance and procedures of conducting genetic research with socially identifiable groups. [source] ,First' appearances in the Cenozoic land-mammal record of the Greater Antilles: significance and comparison with South American and Antarctic recordsJOURNAL OF BIOGEOGRAPHY, Issue 4 2005R.D.E. MacPhee Abstract Aim, Through analysis of fossil records, the aim of this paper is to show that fossil representatives of at least three land-mammal clades (pitheciine atelid primates, heteropsomyine echimyid rodents, and megalonychid phyllophagan xenarthrans) that once lived in the Greater Antilles are as old as, if not older than, ,first' occurrences of these same groups on the South American mainland. Location, Greater Antilles, South America, Antarctic Peninsula. Methods, Analysis of Cenozoic land-mammal fossil records for the three areas. Results, Comparison reveals an interesting similarity to the Tertiary vertebrate palaeontological record for the Antarctic Peninsula (Seymour Island), in the sense that the latter also includes early (Eocene) representatives of some typical ,South American' groups (e.g. meridiungulates, sloths, certain marsupial groups). Conclusions, Given how limited the Antillean and Antarctic records are in quantity and quality, it seems unlikely that these ,first' appearances have much bearing on real origins (basal divergences). Rather, it suggests that the fossil basis for interpreting the origin and earliest diversification of ,South American' clades during the latest Cretaceous/early Cenozoic is probably even scantier than generally realized. In particular, the Antillean record strengthens arguments that some crown-group continental lineages are considerably older than fossil evidence currently allows , a point increasingly (if unevenly) supported by molecular studies of many of the same clades. [source] | ||||||||||