Cláudia Umbelino

The Emergence of Muge Mesolithic Shell Middens in Central Portugal and the 8200 cal yr BP Cold Event

ABSTRACT The emergence of Portugals Muge Mesolithic, with its characteristic shell middens and human burials, is widely seen as a response to the formation of a highly diverse terrestrial and aquatic ecotone in the Tagus basin by the Flandrian transgression. Recently, some have suggested that this was an adaptive response to the 8200 cal yr BP event. Using the available radiocarbon data for the shell middens, paleoclimatic data, and paleoceanographic data we present a new model for the appearance of the Muge Mesolithic shell middens and changes in settlement between the Boreal and Atlantic phases for central Portugal. Coastal ecosystems were altered due to diminution in upwelling and the occurrence of the 8.2 kyr cold event, with declining availability of marine resources, rapid sea level rise, and changes in coastal morphology. The result was that the previous coastal setting was no longer suitable for the hunter-gatherer-fishers causing a settlement shift to the new, large, and stable estuary of the Tagus Valley.

New anthropological data on the Mesolithic communities from Portugal: the shell, middens from Sado

The Portuguese Mesolithic communities are commonly related with the shell middens from Muge from which nearly 300 human skeletons were recovered. There is, however, another important Mesolithic Portuguese site: the shell middens of the Sado Valley, south of Lisbon. Mainly excavated in the 1950s and 1960s by the staff of the National Museum of Archaeology in Lisbon, eleven different shell middens were located (Arnaud, 1989) from which near one hundred skeletons were recovered. In 1982 a long-term multidisciplinary research program, directed by Arnaud, was initiated to relocate and restudy the large amount of artefacts retrieved. Last year, another project involving the Mesolithic-Neolithic transition in Portugal, in terms of paleobiology, started several anthropological analysis of the series bridging this period where the Sado ones are included. In the present paper we present some demographic and paleopathological aspects of Sado assemblage. Despite some of the skeletons being calcified and paraffin embedded, which precluded some anthropological aspects, the general state of preservation allowed a valid paleobiological research. Moreover, in some cases it was possible to reconstruct the original position of the individual interments.The radiocarbon dates already obtained by the team of Arnaud (1989) reveal that this cluster of sites, as in the one from Muge in the Tagus valley, had been occupied over a period of at least 1000 years between the mid-eighth and the mid-seventh millennium BP (Arnaud, 1989). New dates are, nevertheless, presented. The anthropological sample comprises male and female adults as well as an important proportion of sub-adults. The most relevant observations concern dental wear and other oral pathology items such as caries rates.

Sex determination from the femur in Portuguese populations with classical and machine-learning classifiers

The assessment of sex is of paramount importance in the establishment of the biological profile of a skeletal individual. Femoral relevance for sex estimation is indisputable, particularly when other exceedingly dimorphic skeletal regions are missing. As such, this study intended to generate population-specific osteometric models for the estimation of sex with the femur and to compare the accuracy of the models obtained through classical and machine-learning classifiers. A set of 15 standard femoral measurements was acquired in a training sample (100 females; 100 males) from the Coimbra Identified Skeletal Collection (University of Coimbra, Portugal) and models for sex classification were produced with logistic regression (LR), linear discriminant analysis (LDA), support vector machines (SVM), and reduce error pruning trees (REPTree). Under cross-validation, univariable sectioning points generated with REPTree correctly estimated sex in 60.0-87.5% of cases (systematic error ranging from 0.0 to 37.0%), while multivariable models correctly classified sex in 84.0-92.5% of cases (bias from 0.0 to 7.0%). All models were assessed in a holdout sample (24 females; 34 males) from the 21st Century Identified Skeletal Collection (University of Coimbra, Portugal), with an allocation accuracy ranging from 56.9 to 86.2% (bias from 4.4 to 67.0%) in the univariable models, and from 84.5 to 89.7% (bias from 3.7 to 23.3%) in the multivariable models. This study makes available a detailed description of sexual dimorphism in femoral linear dimensions in two Portuguese identified skeletal samples, emphasizing the relevance of the femur for the estimation of sex in skeletal remains in diverse conditions of completeness and preservation.

Ectopic eruption of a lower permanent molar from the mediaeval necropolis of Alcáçova do Castelo, Mértola, Portugal

The mediaeval necropolis of Alcáçova do Castelo is located in Mértola, Southern Portugal, and dates from the 14th to the 16th centuries. The archaeological campaigns started in 1978 and continue today, having yielded more than 759 graves. This report discusses an ectopic tooth eruption observed in skeleton 535, an adult female individual. A distal right permanent lower molar presents an ectopic eruption at the posterior margin of the coronoid process. On the opposite side, the first and second permanent molars are present, the left permanent lower third molar is absent and the mandibular ramus cannot be evaluated since it is broken off and lost. Tooth migration (heteropia) is a common pathological condition documented in clinical literature. However ectopic eruption of lower distal molars is a rare event, and there are few known cases. This is the first case described in archaeological populations worldwide.