Sex identification from the auricular surface of the adult human ilium

The sacro-iliac joint has largely been excluded in studies of sex identification from the adult human skeleton. Yet this is a joint involved in the transmission of body weight and as such would be expected to exhibit sexual dimorphism. In addition, the auricular surface of the ilium tends to persist even in fragmented remains by virtue of its close proximity to the acetabulo-cristal buttress. The aim of this investigation was to assess the accuracy with which sex could be predicted from dimensions of the auricular surface of the ilium. Significant sex differences were found in the size and shape of the auricular surface. However, these differences were of insufficient magnitude to permit discrimination between the sexes with any acceptable degree of accuracy. Therefore, the auricular surface of the ilium is not recommended for the purpose of sex identification.     

Osteoarthritis and body mass

Osteoarthritis is the second most common pathology found in anthropological collections. Although a great deal is known about osteoarthritis, it is not yet known whether in skeletal populations there is a correlation between osteoarthritis and body mass. In this study, lower limb and spinal osteoarthritis scores were taken to determine whether body mass and femoral length correlate with osteoarthritis on weight bearing joints. Osteoarthritis was measured using a four-point ordinal scale on a sample of 114 adult prehistoric Californian Amerinds. Body mass was calculated from femoral head breadth; femoral length was measured using standard procedures; and age and sex were determined through standard osteological procedures. Using Spearman correlations, body mass and femoral length did not correlate significantly with any of the osteoarthritis variables. Age correlated significantly with nearly all of the osteoarthritis variables (hip, r = 0.507; knee, r = 0.528; cervical, r = 0.513; thoracic, r = 0.647; lumbar, r = 0.507, P-values < 0.001); and body mass and femoral length correlated with sex (r-values = 0.835 and 0.654, P-values < 0.001). With age and sex controls, body mass negatively correlated with the hip osteoarthritis variable (r = −0.202, P < 0.05), but not with any of the other osteoarthritis variables. Results concur with previous findings in the anthropological literature and highlight complexities of osteoarthritis etiology.     

A DNA test for sex identification in cattle confirms osteometric results

It is of vital importance to be able to sex identify cattle remains to understand the strategies and importance of cattle husbandry in an ancient society. This is usually done from osteoarchaeological assemblages and often relies on measurements of metapodials. The breadth measurement of the distal trochlea is considered an easy way to identify the sex. Bones from males appears to be easily distinguishable from female counterparts, although it has been complicated to find an external control for the morphological results. Here we investigate the reliability of these particular morphometrics for sex identifying cattle bones with molecular genetics. We use a sex discriminating single nucleotide polymorphism in the ZFXY gene and we apply it to DNA from the bones. To keep the fragment size short and suitable for ancient DNA we base the test on a SNP. The test confirms the osteological sex identification in all cases were DNA could be retrieved. This molecular method can also be used when no fragments suitable for osteological sex identification can be found or when the measurements are non-conclusive.     

Living and dying as subjects of the Inca Empire: Adult diet and health at Puruchuco-Huaquerones,Peru

Imperial strategies varied as the Inca expanded their empire from the capital in Cusco. Some communities were conquered violently while others were ruled indirectly with little evidence of Inca presence. According to ethnohistorical evidence, the central coast was peacefully annexed by the Incas ca. A.D. 1470, but little is known about how Inca imperialism may have affected the quality of life of subjects of the Inca Empire. We integrate multiple lines of evidence to assess diet, health and disease for a sample of human remains from the Late Horizon cemetery of Puruchuco-Huaquerones, Peru. Specifically, we examine and analyze osteological, dental and stable isotope data (n = 162, 90 and 46 respectively) in order to investigate whether the Inca period population at Puruchuco-Huaquerones experienced nutritionally insufficient diets and poor health under imperial policies. Diet at Puruchuco-Huaquerones incorporated a variety of foods, both plant and animal. Osteological lesions and stature indicate periods of stress, with males experiencing more illness relative to females. Stature sexual dimorphism, the presence of healed lesions and isotope data indicate a sufficiently nutritious diet and support the conclusion that, although disease was present, individuals were healthy enough to survive and recover. Geographical and temporal comparisons suggest that health changed little with the Inca annexation of this region, but future work is needed.     

中古典籍中的非类型故事阐释——以《搜神记·羽衣人》为例

《搜神记.羽衣人》故事未见有其它类似记载,笔者将其概括为"非类型",并运用社会学、人类学以及心理学的方法,从蛇的生殖象征角度来解读,得出了"飞蛇幻化为女人,‘淫’凡男‘谷’,使其怀孕并留于宫中"的结论,进而指出这种非类型故事在民间传承中的产生原因及其生存条件。     

Accurate sex identification of ancient human remains using DNA shotgun sequencing

Accurate identification of the biological sex of ancient remains is vital for critically testing hypotheses about social structure in prehistoric societies. However, morphological methods are imprecise for juvenile individuals and fragmentary remains, and molecular methods that rely on particular sex-specific marker loci such as the amelogenin gene suffer from allelic dropout and sensitivity to modern contamination. Analyzing shotgun sequencing data from 14 present-day humans of known biological sex and 16 ancient individuals from a time span of 100 to ∼70,000 years ago, we show that even relatively sparse shotgun sequencing (about 100,000 human sequences) can be used to reliably identify chromosomal sex simply by considering the ratio of sequences aligning to the X and Y chromosomes, and highlight two examples where the genetic assignments indicate morphological misassignment. Furthermore, we show that accurate sex identification of highly degraded remains can be performed in the presence of substantial amounts of present-day contamination by utilizing the signature of cytosine deamination, a characteristic feature of ancient DNA.     

Sex identification of ancient DNA samples using a microfluidic device

A microfluidic device has been developed for the sex identification of ancient DNA samples and works by manipulating liquids within an environment of micrometer dimensions. In this work a range of microfluidic DNA extraction methods were evaluated for their compatibility with ancient DNA samples, and the use of streptavidin-coated super paramagnetic particles to isolate biotin-labeled abasic sites within damaged DNA was shown to be the most reproducible. Polymerase chain reaction-based DNA amplification was possible on the microfluidic device when less than 50 pg of template DNA was added. As a proof-of-principle, powdered bone samples were analysed using the integrated methodology developed. Following conventional capillary gel electrophoresis, two out of the three samples produced positive amplification results and were successfully identified as female. These sex identifications were corroborated by independent Amelogenin, anthropological and Y chromosome analysis. The work reported here is the first step in the development of a complete miniaturized microfluidic system that would enable on-site ancient DNA analysis.     

Sample-specific (universal) metric approaches for determining the sex of immature human skeletal remains using permanent tooth dimensions

In this paper, three approaches for developing sample-specific sex determination methods of immature skeletal remains based on permanent tooth dimensions are proposed and tested using a sample of identified skeletons. The sample comprises adult and subadult individuals selected from the Lisbon documented skeletal collection, housed at the National Museum of Natural History in Lisbon, Portugal. Faciolingual and mesiodistal diameters were the tooth dimensions utilized. In the first approach, sex-specific logistic regression formulae based on adult tooth dimensions are developed and then used to determine the sex of the subadult sample. The second and third approaches are based on the sectioning point procedure, which uses the overall mean of a measurement (tooth diameter) collected from the sample as the discriminant criteria for determining the sex of the individuals in that sample. While in the second approach the adult overall mean of each dimension is used as the discriminant criteria for determining the sex of the subadults, in the third approach it is the subadult overall mean of each dimension that comprises the discriminant criteria that is applied back to the subadults for determining sex. Results show that the canines are the teeth with the highest sexual dimorphism and methods of sex determination based on canine dimensions provide correct allocation accuracies between 58.8% and 100% depending on the diameter and the approach that is being used. Canine faciolingual dimensions provide the best overall results. Combinations of measurements from the same and different teeth do not increase significantly the accuracy of the methods and approaches. Some of the problems of subadult sex determination methods based on adult tooth dimensions result from differing levels of sexual dimorphism between the adult and subadult segment of the sample. Mortality or cultural bias may increase or decrease the sexual dimorphism of the subadults compared to the adults. Small subadult samples utilized in this study may also raise questions regarding the accuracy of the three different sample-specific approaches. However, high consistency of results using the canine and different approaches, suggests that adult and subadult canine dimensions can be reliable sex discriminators of immature skeletal remains in archaeological samples. The major advantage of the approaches presented here is that they can be used to derive sample-specific methods and, therefore, eliminate the problem of applying morphological or metric methods to individuals originating from a population that differs from the one that contributed to the development of the method.     

Sexing the Self: Geographies of engagement and encounter

Geographic research on the construction of sexual identity takes inspiration from two main sources. The first is the post-structural literature that suggests sexual subjects are sutured to identities created in the realms of discourse. The second is a psychoanalytical tradition concerned with the desires and disgusts experienced by sexual subjects as they seek to reconcile their inner selves with the outside world. In this paper an attempt is made to combine these contrasting perspectives by exploring the way sexualities are negotiated by individuals as they encounter a world that is both real and imagined. The utility of this approach is illustrated with reference to the author's research on sex work, which demonstrates that the making of sexual identities involves a dynamic relation between Self and Other--a relation that is subsequently encoded in representations of space. The paper concludes that the making of sexual identities can only be understood by examining the ways that representation and experience entwine in specific places to create sexual identities that are fractured, contested and always becoming.     

Sex ratios and life tables: Historical demography of the age at which women outnumber men in seven countries, 1850–2016

Abstract

The male/female sex ratio (SR) and its age-specific patterns vary considerably across time and place. The SR generally begins male-biased at birth and becomes female-biased later in life, but this relationship should respond to historical trends and events. Temporal trends in SRs remain largely unstudied and formal demographic relationships are not well defined. We (1) define SRs in a life table framework, (2) estimate the age at which the number of males and females achieves parity—the sex ratio crossover (SRX)—using basic life table methods, and (3) explore historical and international patterns in these trends. Using publicly-available data from the Human Mortality Database, we construct SR and SRX measures from period and cohort life tables. Analyses explore temporal patterns for seven countries in different global regions since 1850. Overall temporal trends show the SRX advancing to older ages. The SRX also appears to respond to historical events such as wars and epidemics. The measure is simple to construct from life table data, and provides additional insight into the historical context of gender dynamics.