Non-metric dental analysis of human interactions around the Pyrenees during the Neolithic and their biological impact.

BACKGROUND: Interactions across the Pyreneans during the Middle-Neolithic (V-IV millennium BCE) have been described for a long time. Nevertheless, except for a few examples and attempts to describe them, the biological impact of these interactions on the human groups' make-up is not yet understood. The present work analyzes the biological affinities of different groups from both sides of these mountains that represent the Populations of the Middle- and Late-Neolithic by means of the dental morphology. METHODS: We present novel dental morphological data of 221 individuals from 11 archaeological sites. These data have been analyzed and compared to those from previously published twenty Iberian sites and one French site. Data were recovered following the ASUDAS protocol, and MMD biological measure was calculated between groups. RESULTS: Our results suggest that there were some differences between the analyzed populations. These differences were observed at each side of the Pyrenees, but also across them. Concretely, the coastal groups across the mountains show more affinities between each other than the inland groups. In addition, the differences between groups decreased by the end of the Neolithic. CONCLUSIONS: Therefore, our results indicate that the intense trade activities registered in the coastal area between both sides of the Pyrenees would have had the greatest biological impacts in the homogenisation of the groups. Although less intense, the across mountain network and coastal to mountain area trade networks to the south of Pyreneans, also influenced the biological make-up of the groups.

From early to late modern societies (late 16th - early 20th century): Shifts in dental health status in two populations from southeastern France.

In France, bioarcheological research has long overlooked the early and late modern periods, which witnessed major transformations impacting population structure and leading to the dawn of modern industrialized societies. Two recently excavated large cemeteries in Provence present a unique opportunity to investigate on a large scale the impact on health and living conditions brought about by the Industrial Revolution and consequently track health status changes from the 16th to the early 20th century. The sample includes 642 individuals from the early modern cemetery of Saint-Jacques, La Ciotat (1581-1831) and the late modern cemetery of Les Crottes, Marseille (1784-1905). This study aims to document dental health markers and compare the results between both assemblages, considering ante-mortem tooth loss, wear, caries, abscesses, calculus, periodontitis and linear enamel hypoplasia. The available archaeological and historical sources for these recent periods provide a full documentation in which to interpret and discuss the biological analysis, thus enabling an inclusive bioarcheological approach. RESULTS: revealed similarities between both samples. Differences are more subtle than expected and are seen through the increase in carious lesions and in linear enamel hypoplasia. The former seem to indicate changes in diet with the introduction of new foodstuffs and manufacturing processes during the Industrial Revolution. The latter could reflect the increase in early childhood stress, perhaps due to new feeding practices around weaning and breastfeeding or a poorly diversified diet. Finally, the increasing number of stress events could suggest a noxious sanitary and infectious environment. During the 19th century, Marseille experienced strong demographic and urban growth, resulting in overcrowded areas where sanitation facilities were insufficient or absent. Moreover, the activity of this important trading seaport might have promoted the transmission and appearance of epidemic diseases despite scientific and medical advances, which would have a real impact only from the 20th century onwards.

Using histomorphometry for human and nonhuman distinction: A test of four methods on fresh and archaeological fragmented bones.

Positive identification of human remains is the very first step in anthropological analysis, and the task may be particularly difficult in the case of fragmented bones. Histomorphometry methods have been developed to discriminate human from nonhuman bones, based on differences in the size and shape of Haversian systems between the two groups. Those methods all focus on a very specific type of bone, section, and zone. Therefore, the objective of this study was to test the efficiency of four histomorphometric methods on a sample of fragmented bones. The sample is composed of 37 archaeological and fresh specimens, 25 nonhumans (Bos taurus, Equus caballus, Sus scrofa, Capreolus, Canis familiaris, Cervus elaphus, Ovis, and Capra) and 12 humans (Homo sapiens). Eight histomorphometric criteria were collected from all intact osteons visible on each fragment and then inserted into the corresponding discriminate function of each method. The results were compared with the real origin to establish rates of correct classification for each method. The methods of Martiniaková et al. (2006) and Crescimanno and Stout (2012) obtained very low percentages of good classification (32 % and 67 %). Those of Cattaneo et al. (1999) obtained 94 % correct classification, but only after a correction of the units of measurement for Haversian canal area in their formula. The methods of Dominguez and Crowder (2012) obtained an 86 % rate for well-classified specimens. Some of the methods tested here contain errors in the original publication that make them unusable in their current state. Plus, it seems that histomorphometric methods developed from specific areas are more difficult to apply to fragments. A reduced number of intact osteons analyzed may partially affect the reliability of the method by being unrepresentative of the entire microstructure. Therefore, this study demonstrates that one should be cautious with the use of histomorphometric methods to distinguish human and nonhuman fragmented bone until further research can refine these methods to achieve greater reliability.

Molecular detection of Treponema pallidum subspecies pallidum in 150-year-old foetal remains, southeastern France.

PURPOSE: Syphilis, caused by Treponema pallidum subspecies pallidum , is considered as an old disease affecting humans; traces of such infections, including congenital syphilis, are potentially identifiable in archaeological samples. The aim of this research was to perform macroscopic and molecular investigations of T. pallidum on six infant remains, buried between 1837 and 1867, from the cemetery of 'Les Crottes' in Marseille city (southeastern France). METHODOLOGY: Pathological analysis of bones from individuals, aged from the twenty-ninth week of amenorrhea to 4-9 months, was performed. Samples served also as a source of ancient DNA (aDNA) for PCR-based molecular investigations targeting T. pallidum DNA; all samples were also tested for Mycobacterium tuberculosis and Plasmodium falciparum DNA. Sequences characterized were cloned and sequenced, and compared to those available in databases.Results/Key findings. All samples tested displayed widespread osteoporotic lesions across the skeleton possibly related to some metabolic or infectious disorders. Subsequent molecular analysis revealed that one individual, SP332 (unborn, 29 amenorrhea weeks, inhumation date 1864-1866), exhibited positive signals for the five T. pallidum amplification systems tested; sequence analysis provided strong evidence for the effective detection of T. pallidum subspecies pallidum DNA. CONCLUSIONS: Individual SP332 is the first PCR-confirmed palaeopathological case of syphilis identified in France, and the youngest specimen ever to be diagnosed with certainty for congenital syphilis. Future research aimed at better characterizing this 150-year-old treponeme genome and exploring new archaelogical cases of syphilis in the very young should contribute to a better comprehension of the disease's history.

The age at death assessment in a multi-ethnic sample of pelvic bones using nature-inspired data mining methods.

Recently published studies showed that age assessment methods are population specific. Authors analyse the senescence changes in pubic symphysis and sacro-pelvic surface of a pelvic bone using data mining methods. The multi-ethnic data set consists of 956 adult individuals ranging from 19 to 100 years of age derived from 9 different populations with known age and sex. The results show that accurate and reliable age assessment is possible to three age classes (less than 30, 30-60, 60 and more). The study confirms that population specificity of the methods exists and the variable "sex" is not important in age classification.

Estimation of age at death from the pubic symphysis and the auricular surface of the ilium using a smoothing procedure.

We discuss here the estimation of age at death from two indicators (pubic symphysis and the sacro-pelvic surface of the ilium) based on four different osteological series from Portugal, Great-Britain, South Africa or USA (European origin). These samples and the scoring system of the two indicators were used by Schmitt et al. (2002), applying the methodology proposed by Lucy et al. (1996). In the present work, the same data was processed using a modification of the empirical method proposed by Lucy et al. (2002). The various probability distributions are estimated from training data by using kernel density procedures and Jackknife methodology. Bayes's theorem is then used to produce the posterior distribution from which point and interval estimates may be made. This statistical approach reduces the bias of the estimates to less than 70% of what was obtained by the initial method. This reduction going up to 52% if knowledge of sex of the individual is available, and produces an age for all the individuals that improves age at death assessment.

An evaluation of statistical methods for the determination of age of death using dental root translucency and periodontosis.

Lamendin and colleagues (1992) proposed to assess age-at-death from root translucency and periodontosis. Several teeth from the same individual were included in their study. In our work, we evaluate the reliability of their formulas without introducing this bias. Our sample was constituted of 214 individuals (114 males and 100 women) selected from the Terry collection (U.S.A.). The R(2) between age and both indicators is equal to 0.33 and 0.08 (p < 0.001). Based on linear regression, the mean of standard error for individual age prediction was equal to 13.67 years, and the mean interval length is equal to 53.89 years. Multinomial logistic regression and Bayesian approach failed to give satisfactory results when classifying the individuals in age categories. Therefore, the use of root translucency and periodontosis may lead to incorrect age-at-death assessment, and it is thus necessary to complement this approach with other techniques to assess age-at-death.

Aging process variability on the human skeleton: artificial network as an appropriate tool for age at death assessment.

Adult age-at-death assessment is one of the most difficult problem encountered in paleoanthropology. Many procedures have been proposed using either skeletal remains or dental records, but most show systematic bias. Data processing of current methods are a source of error because they neglect that process of biological ageing is very variable between individuals and populations. The aim of this study is to test the potentiality of artificial neural networks (ANN) as a prediction tool. ANN have been used for a wide variety of applications where statistical methods are traditionally employed. But it performs better to solve linearly non separable patterns. We applied this technique after observation of several features' aging changes of the pubic symphysis and the auricular surface of the ilium. Although we failed to reduce the size of the intermediate class (30-59 years), the neural network identifies, with better reliability than previous works, the youngest (20-29 years) and the oldest (above 60 years) individuals.

Variability of the pattern of aging on the human skeleton: evidence from bone indicators and implications on age at death estimation.

Age at death assessment of adult skeletons is one of the most difficult problems in forensic and physical anthropology. Two fundamental sources of error are described: the complex variability in the process of skeletal aging and methodological bias. Taking into account these limits, we developed a new scoring system for the auricular surface of the ilium and the pubic symphysis. In order to address a large variability, we examine reference samples from Europe, North America, Africa, and Asia. Data were processed using Bayesian prediction in order to classify specimens in age range categories. Results show that combining indicators do not perform better than the auricular surface used as a single indicator. Morphological changes with aging are variable between Asian, African, and European populations, confirming the necessity to use population-specific standards. Bayesian prediction produces reliable classification and is applicable for subjects over 50 years old, a real methodological improvement.