Sexing Adult Pale-Winged Starlings Using Morphometric and Discriminant Function Analysis

Accurate sexing of birds is vital for behavioral studies but can be a real problem in the field, especially for monomorphic species. Our goal here was to characterize the morphology of male and female monomorphic pale-winged starlings (Onychognathus nabouroup), a South African sturnid whose plumage is sexually monomorphic. Morphological measurements of genetically sexed animals indicated that males were statistically larger than females for five measurements: Mass, tail length, tarsus length and wing length. By using a Discriminant Function Analysis based on the measurements taken by one ringer, we were able to predict correctly the sex of 81.10% of the birds of data collected in the field and 77.9% of museum skins independently of year of capture and ringer. The model developed here should be useful for further field studies of this species.     

Complexity in Arikara Mortuary Practice

Abstract

Traditionally, Arikara mortuary practice has been described as direct interment soon after death in wood-covered pits. This interpretation explains most of the ethnohistorical and archeological data, but not all. Some ethnohistorical, archeological, and entomological evidence suggests scaffolding prior to burial.     

河北阳原姜家梁新石器时代人类牙齿形态特征的观察与研究

本文应用牙齿人类学的研究方法,对出自河北阳原姜家梁遗址的新石器时代居民的牙齿形态特征进行了研究。采用“亚利桑那州立大学牙齿人类学系统”进行牙齿形态观察,应用“平均差异度”(MMD)距离公式计算出姜家梁组与其他各对比组的MMD距离系数以估计群体间的相似程度,并根据MMD矩阵对18组人群进行聚类分析和因子分析。本文研究结果表明,姜家梁居民的牙齿形态特征属于中国型牙(Sinodonty),但自身又具有某些独特的特征,如铲形上颌中央门齿和单根上颌第一前臼齿等特征的出现率很高。综合来看,姜家梁组在铲形上颌中央门齿、双铲形上颌中央门齿、单根上颌第一前臼齿和第一臼齿转向皱纹这4项性状上具有很高的出现率;上颌第一臼齿釉质延伸、上颌第三臼齿退化、三根下颌第一臼齿和下颌第二臼齿四尖这四项性状出现率处于中等水平。与同时代的下王岗组和庙子沟组比较而言,姜家梁组与庙子沟组的关系更为密切,有研究表明姜家梁组居民与庙子沟组居民具有较为相近的头骨形态特征,本文研究结果表明两者具有较为接近的牙齿形态特征,这说明在体质特征上相近的人群在头骨形态特征和牙齿形态特征方面的表现可能较为一致,但只通过这两个对比组的比较结果而下此结论还为时过早,尚有待于积累更多的同类型族群的相关牙齿人类学资料验证之。     

Skeletal growth of the protohistoric Arikara.

The longitudinal growth of the long bones and growth in breadth of the ilium are assessed for a population of protohistoric Arikara Indians from South Dakota through the correlation of skeletal measurements with estimates of chronological age at death. Comparison of the Arikara growth data with those from other Indian samples (Indian Knoll and Late Woodland, Illinois) reveals similar rates of bone growth, when compensation is made for methodological variation. As predicted from documented variation in adult statures, the Indian samples indicate slower growth rates than those of Whites but faster than those of Eskimos.     

Sexing schistosome larvae

Biological and immunological factors may influence changes in sex ratios at different points of the schistosome life cycle, resulting in the fact that female schistosomes are significantly outnumbered by males in chronic infections of snails and mammalian hosts. Analysis of this phenomenon has long been hampered by shortcomings in the methods used to determine sex ratios. Here, Robin Gasser describes recently developed molecular methods for sexing schistosome larvae. These have opened the way towards understanding why sex ratios become male biased and allow a proper assessment of its consequences in the epidemiology, diagnosis and pathology of infection.     

Seasonal Economic and Settlement Patterns of the Arikara

Abstract

That the Arikara were characterized by seasonal economic activities accompanied by varying settlement patterns during the Late Prehistoric and EarlyContact Periods is amply documented in the archaeological records and journals of the first explorers of the Missouri Valley. In spite of the abundant data, however, several aspects of the seasonal changes of economic and settlement patterns still remain subjects of speculation. Since there seems to have been so much regional and time variation in these patterns the observations presented in this report should be considered tentative.     

Sexing the human sternum

For differentiating a male from a female sternum, a metrical study of 400 adult North Indian sterna (312 males and 88 females) obtained from medicolegal postmortems was made. If the combined length of the manubrium and mesosternum was more than 140 mm. the sternum was male, and if less than 131 mm. it was female. No opinion could be given if the length was between 131 and 140 mm. By this measurement 72.12% male and 62.50% female sterna could be sexed with 100% accuracy. The length of the mesosternum alone could also determine the sex correctly in 50.32% male and 29.55% female specimens. The length of the manubrium, manubrium–corpus index, width of the first or third sternebra or their index, were not found to be useful in sexing a given sternum. By using multivariate analysis the probability of correctly identifying the sex of a sternum was over 85%.     

Non-carious interproximal grooves in Arikara Indian dentitions.

The dentitions of adult Arikara Indians from the Larson site (39WW2) were examined to determine the frequency and etiology of noncarious interproximal grooves. The observations included groove morphology, loci and association with dental pathology. Approximately 30% of the individuals exhibit one or more pronounced grooves. The use of dental probes in conjunction with dietary grit is the likely responsible for interproximal grooves in this population sample.     

Morphological Differences Between Mandan And Historic Arikara Crania

Abstract

Arikara cranial measurements are compared with Mandan data to define the nature and magnitude of differences remaining at the beginning of the Historic period. A discriminant function approach is followed. Special attention is given to determining uniqueness of the two sets of crania as estimated by rates of group misclassification. Three validation procedures are applied in estimating these rates: resubstitution, jackknife, and holdout.

Several variables show significant heterogeneity between Arikara and Mandan including nasal height, maximum cranial breadth, and auricular height. Mandan crania tend to be narrower, have less nasal height, and are lower in auricular height. Functions developed for Leavenworth Arikara and Mandan crania have an accuracy of about 84 percent. Data for the Leavenworth Site are expanded with addition of a sample excavated by William H. Over 60 years ago.     

Cranial Variation and Microevolution in Arikara Skeletal Populations

Abstract

Crania from six archaeological sites in South Dakota are analyzed. Chronologically the sites fall into two groups, an early group and a late group, with A.D. 1750 as the approximate boundary between them. It is shown that the late group is morphologically diverse, while the early group is relatively homogeneous. The morphological pattern is related to the increasing intensity of evolutionary processes as the contact period progressed.     

Long bone growth variation among Arikara skeletal populations

Long bone growth variation among skeletal samples has had limited application to ecological studies of archaeological groups, in spite of its well-known sensitivity to health and nutritional status. In this study we examine long bone growth variation among ten samples of Arikara skeletal groups, all located in the Middle Missouri subarea of South Dakota and ranging in time from A.D. 1600 to 1832. The samples are analyzed by variant, an archaeological taxonomic unit below Tradition. Children's long bones between about 0.5 and 11.9 years of age were analyzed by means of regression using the model, bone length =b₀ + b₁ (age) + b₂ (log₁₀ age). The three variants, Extended Coalescent, Postcontact Coalescent, and Disorganized Coalescent, differ from one another with regard to health and nutritional status. Extended Coalescent groups probably experienced periods of undernutrition due to unfavorable climatic conditions prevailing at the time. Postcontact Coalescent groups experienced more favorable health and nutrition due to improved climatic conditions and introduction of the horse. Disorganized Coalescent groups were exposed to undernutrition and high levels of morbidity, due to introduction of epidemic diseases, depopulation, and intertribal conflict. Analysis of slopes shows significant heterogeneity among variants for humerus, radius, and tibia, but not femur. In general, the Postcontact Coalescent is characterized by slighter greater rates of increase with age and longer bone lengths for each age than is Extended Coalescent. Disorganized Coalescent exhibits lower rates of increase, particularly in later childhood, with shorter bone lengths in late childhood. Disorganized Coalescent also presents longer radius and humerus lengths than the other two variants in early childhood, an unexpected finding. This may be partly, but not entirely, explained by differential bone response to stress along the lines of maturity gradients.     

鸟类性别鉴定技术研究进展

鸟类性别鉴定曾经通过外科手术对生殖腺直接进行检测,此法不仅繁琐而且有时会导致鸟的不育;细胞学水平上鉴定性别是通过直接观察W、Z性染色体而进行,但由于染色体数目大、分散难度高,很容易引起人为的主观因素导致结果错误。近年来利用鸟类W染色体上的性连锁基因或DNA序列,通过PCR、原位杂交等技术建立起来的．DNA分子水平性别鉴定方法,发展迅猛,准确度高,操作简便。此技术一旦形成体系,对鸟类研究、濒危物种保存等都将具有非常重要的意义。     

Microevolutionary change in Arikara Crania: a multivariate analysis

Measurements of human crania from five archaeological sites were subjected to canonical analysis. The five sites form a temporal sequence, ranging from prehistoric (ca. 1600 A.D.) to late historic (1830 A.D.), and belonging archaeologically to the Coalescent Tradition, which in South Dakota encompasses the historic Arikara Indians and their prehistoric ancestors. One canonical variate in each sex arranges the sites in their appropriate temporal sequence, presumably reflecting systematic microevolutionary change. The hypothesis that the morphological change resulted from gene flow from either White or Mandan Indian sources was tested using a two-group discriminate function. The function is found to effectively discriminate a Mandan sample and prehistoric Arikara, but becomes progressively less effective on the historic Arikara crania. This would suggest that Mandan gene flow into Arikara populations is responsible for the observed temporal variation. A similar analysis using British White crania suggests the possibility of slight White influence, but the effect is minimal compared to Mandan.     

The Avifauna from Prehistoric Arikara Sites in South Dakota

Abstract

During an approximate 15-year period from about 1950 to 1965, numerous anthropologists representing at least a dozen institutions were periodically involved in archaeological salvage of Plains sites in the Middle Missouri Valley. In many instances the cultural aspects of subsistence and the utilization of native fauna in general were not of primary interest. However, some animal bone was salvaged and this discussion involves the study of the avian remains from 51 prehistoric Arikara sites along the Missouri River in South Dakota. Approximately 3,100 bird elements, representing 22 families and about 68 species, were identified. Although mammals, especially the bison, elk, deer, and pronghorn, provided the greatest quantity of meat in the diet of these people, birds were also of special significance as supplemental food (e.g. waterfowl, grouse) and because of the part they played in the cultural and ceremonial activities of the Plains Indian. The predominance of remains of such groups as eagles, hawks, harriers, owls, and ravens in these sites is indicative of their special cultural significance; in some instances, such as eagle trapping by the Hidatsa and Mandan, they can be correlated with ethnohistoric accounts dealing with the utilization of birds.