The impact of antimeric lower limb length asymmetry on adult stature estimation.

Antimeric lower limb length asymmetry is frequently noted when measuring human skeletal remains. As lower limb bones are often used to estimate stature from unidentified remains, the forensic anthropologist who notes a disparity must then determine which lower limb bone or bones will produce an estimate that most accurately and precisely captures the unknown individual's stature. To help forensic anthropologists make informed decisions when remains exhibit lower limb antimeric asymmetry, left and right femora and fibulae maximum lengths were analyzed from 78 DPAA-identified individuals with measured statures. Results revealed 87.2% of individuals exhibited lower limb antimeric asymmetry, statistically significant differences between lower limb lengths, decreasing estimate accuracy when asymmetry increased, and that using a 99% prediction interval for disparities ≥5.0 mm nearly ensured documented measured stature would be captured. These findings were validated on independent samples of 20 adult males from the DPAA and 146 males and females from the Terry, Hamann-Todd, and Bass Collections. Preliminary results were largely supported; however, the accuracy reduction with increasing asymmetry observed in the DPAA data was not replicated. Based on these findings, we encourage bilateral measurement taking to identify lower limb antimeric asymmetry, caution against combining bone lengths from opposite sides, and recommend using a 99% prediction interval when lower limb length antimeric asymmetry is ≥5.0 mm and if using the FORDISC 3 Trotter M Stats database. When C Stats or F Stats are used, the prediction intervals associated with these less homogeneous databases are large enough to absorb error due to antimeric asymmetry.

Assessment of nutritional stress in famine burials using stable isotope analysis.

OBJECTIVES: We compared δ15 N and δ13 C values from bone and dentine collagen profiles of individuals interred in famine-related and attritional burials to evaluate whether individuals in medieval London who experienced nutritional stress exhibit enriched nitrogen in bone and tooth tissue. Dentine profiles were evaluated to identify patterns that may be indicative of famine during childhood and were compared with the age of enamel hypoplasia (EH) formation to assess whether isotopic patterns of undernutrition coincide with the timing of physiological stress. MATERIALS AND METHODS: δ15 N and δ13 C isotope ratios of bone collagen were obtained from individuals (n = 128) interred in attritional and famine burials from a medieval London cemetery (c. 1120-1539). Temporal sequences of δ15 N and δ13 C isotope profiles for incrementally forming dentine collagen were obtained from a subset of these individuals (n = 21). RESULTS: Results indicate that individuals from attritional graves exhibit significantly higher δ15 N values but no significant differences were found between burial types for the sexes. Analyses of dentine profiles reveal that a lower proportion of famine burials exhibit stable dentine profiles and that several exhibit a pattern of opposing covariance between δ15 N and δ13 C. EH were also observed to have formed during or after the opposing covariance pattern for some individuals. CONCLUSIONS: The results of this study may reflect differences in diet between burial types rather than nutritional stress. Though nutritional stress could not be definitively identified using bone and dentine collagen, the results from dentine analysis support previous observations of biochemical patterns associated with nutritional stress during childhood.

Genetic resiliency and the Black Death: No apparent loss of mitogenomic diversity due to the Black Death in medieval London and Denmark.

OBJECTIVES: In the 14th century AD, medieval Europe was severely affected by the Great European Famine as well as repeated bouts of disease, including the Black Death, causing major demographic shifts. This high volatility led to increased mobility and migration due to new labor and economic opportunities, as evidenced by documentary and stable isotope data. This study uses ancient DNA (aDNA) isolated from skeletal remains to examine whether evidence for large-scale population movement can be gleaned from the complete mitochondrial genomes of 264 medieval individuals from England (London) and Denmark. MATERIALS AND METHODS: Using a novel library-conserving approach to targeted capture, we recovered 264 full mitochondrial genomes from the petrous portion of the temporal bones and teeth and compared genetic diversity across the medieval period within and between English (London) and Danish populations and with contemporary populations through population pairwise ΦST analysis. RESULTS: We find no evidence of significant differences in genetic diversity spatially or temporally in our dataset, yet there is a high degree of haplotype diversity in our medieval samples with little exact sequence sharing. DISCUSSION: The mitochondrial genomes of both medieval Londoners and medieval Danes suggest high mitochondrial diversity before, during and after the Black Death. While our mitochondrial genomic data lack geographically correlated signals, these data could be the result of high, continual female migration before and after the Black Death or may simply indicate a large female effective population size unaffected by the upheaval of the medieval period. Either scenario suggests a genetic resiliency in areas of northwestern medieval Europe.

Urban and rural mortality and survival in Medieval England.

BACKGROUND: Late medieval England underwent intensive urbanisation, particularly in its largest city: London. Urban dwellers were exposed to factors such as high population density, elevated risk of infection, unsanitary living conditions and precarious food supplies. AIM: To assess whether the urban environment was more detrimental to health than the rural environment, this study compares risks of mortality and survival, as proxies for health, in medieval urban vs rural England. SUBJECTS AND METHODS: This study uses samples from rural St. Peter's cemetery in Barton-upon-Humber, Lincolnshire (c. 1150-1500) and urban St. Mary Spital cemetery in London (c. 1120-1539). Cox proportional hazards analysis and Kaplan-Meier survival analysis are used to assess differences in mortality and survival between urban and rural environments, including differences between sexes. RESULTS: The results indicate that urban adults faced elevated risks of dying and reductions in survivorship. Specifically, urban females faced elevated risks of dying and reductions in survivorship, while the risks for males were similar in both environments. DISCUSSION: These results suggest that the effects of urbanisation in medieval England varied by sex. Deleterious conditions associated with urbanisation in London were hazardous for adults, particularly females who may have migrated into London from rural areas for labour opportunities.

Sex differentials in caries frequencies in Medieval London.

OBJECTIVE: Tooth decay is one of the most common oral infections observed in skeletal assemblages. Sex differentials in caries frequency are commonly examined, with most studies finding that females tend to have a higher frequency of carious lesions (caries) compared to males. Less research has examined differences in caries between males and females with respect to age in past populations. Findings from living populations indicate that caries frequencies are higher in females, at least in part, because of the effects of estrogen and pregnancy. We are interested in the interaction of age, sex, and caries in medieval London, during a period of repeated famines, which might have exacerbated underlying biological causes of caries sex differentials. DESIGN: We examined caries in adults from two medieval London cemeteries dating to c. 1120-1539 AD: St. Mary Spital (n=291) and St. Mary Graces (n=80) to test the hypothesis that males and females have different caries frequencies irrespective of age. The association between maxillary molar caries and sex was tested using hierarchical log-linear analysis to control for the effects of age on caries frequencies. RESULTS: The results indicate a higher frequency of maxillary molar caries in females (P<0.00), and that the age distribution of caries differs between the sexes (P=0.01), with a consistent increase in frequency with age for females until late adulthood, but not males. CONCLUSIONS: The difference in caries frequencies is not explained by differences in the age distributions of the sexes. Differences in the age patterns of caries for males and females could be the result of biological factors that present during reproductive age, differences in diet, or differential access to resources during famine.

Mapping simulated scenes with skeletal remains using differential GPS in open environments: an assessment of accuracy and practicality.

Scene mapping is an integral aspect of processing a scene with scattered human remains. By utilizing the appropriate mapping technique, investigators can accurately document the location of human remains and maintain a precise geospatial record of evidence. One option that has not received much attention for mapping forensic evidence is the differential global positioning (DGPS) unit, as this technology now provides decreased positional error suitable for mapping scenes. Because of the lack of knowledge concerning this utility in mapping a scene, controlled research is necessary to determine the practicality of using newer and enhanced DGPS units in mapping scattered human remains. The purpose of this research was to quantify the accuracy of a DGPS unit for mapping skeletal dispersals and to determine the applicability of this utility in mapping a scene with dispersed remains. First, the accuracy of the DGPS unit in open environments was determined using known survey markers in open areas. Secondly, three simulated scenes exhibiting different types of dispersals were constructed and mapped in an open environment using the DGPS. Variables considered during data collection included the extent of the dispersal, data collection time, data collected on different days, and different postprocessing techniques. Data were differentially postprocessed and compared in a geographic information system (GIS) to evaluate the most efficient recordation methods. Results of this study demonstrate that the DGPS is a viable option for mapping dispersed human remains in open areas. The accuracy of collected point data was 11.52 and 9.55 cm for 50- and 100-s collection times, respectfully, and the orientation and maximum length of long bones was maintained. Also, the use of error buffers for point data of bones in maps demonstrated the error of the DGPS unit, while showing that the context of the dispersed skeleton was accurately maintained. Furthermore, the application of a DGPS for accurate scene mapping is discussed and guidelines concerning the implementation of this technology for mapping human scattered skeletal remains in open environments are provided.