Behavioral Adaptations - Morphological Adaptations: new contributions from Morphometric Mapping for the understanding of Mesolithic-Neolithic transformations (Balkans; 10 000 - 5000 BC).
de Becdelievre Camille;
Le Guen Marc-Antoine;
A major transition occurred during the Early-middle Holocene: Humans entered a new adaptive niche by settling in favored environments
and by domesticating other species. Today, a growing body of archaeological evidence documents the timing of this
transition and the study of prehistoric human remains relates this process to specific bodily adaptations. However, it is noteworthy
that: 1. varying methodologies and heterogeneous markers have been used; 2. these different markers of physical activity - of
different nature and relating complementary biological information - have barely been compared; 3. because of the availability of
well-preserved samples, these markers could not always be applied to ecologically homogeneous population or to population for
which multiple archaeological line of evidence on subsistence strategies were available. The context of Danube Gorges prehistoric
sites (Balkans, 9500-5500 BC) - where the remains of more than 500 human skeletons have been discovered - well-contextualized
and covering a sequence spanning the whole Mesolithic and the Early Neolithic - provides the opportunity to analyze jointly behavioral
and morphological adaptations on an homogeneous Early Holocene population. The sites of the Lepenski Vir culture
document the gradual transformations of mobile hunter-gatherers and fishermen (Early Mesolithic) toward a population of sedentary
fishermen (Late Mesolithic - Early Neolithic), which adopted ceramics and finally practiced animal husbandry (Neolithic).
Recent results of geochemical analyses indicate that a number of Neolithic individuals were non-locals, originating in some geologically
differentiated areas outside the Danube Gorges; these migrants may have brought Neolithic socio-cultural novelties in the
gorges (ceramics, polished axes, new type of flint used for tools, different adornments, new funerary gestures...). Therefore, in this
study, bone markers of physical activities (enthesopathology, osteoarthrosis) have been analyzed on a sample of 200 adults individuals,
together with a new technique of virtual analysis specifically applied on humerus and femurs: morphometric mappings. This
technique considers the diaphyses of long bones as "tubes" which can be virtually unrolled and read like maps; measurements of the
external topography of diaphyses (the robusticity of muscles attachments), of the thickness of cortical bone (bone robusticity) and
of the internal geometry of bones (second moments area) are virtually taken all along the diaphysis and then projected like maps.
These morphometric maps enable thereby to locate with precision along the whole diaphysis the main differences in term of muscle
attachments, cortical thickness and bone geometry. Plus, the technique also enable to obtain "average maps" of groups of individuals,
which makes possible statistical comparisons. Results: 1. confirm long bone morphological adaptation to sedentism, especially
a gradual and diachronic trend of systematic decline in lower limbs robusticity, a trend toward more circularity in the geometric
sections of lower limbs mid-shaft diaphyses, a reduction in the robusticity of specific entheseal sites and a decline in the extent of
pathological entheseal sites located on the lower limbs; 2. suggest a sexual dimorphism possibly correlated to the first development
of a sexual division of labor; 3. indicate that the inner bone morphology as well as outer topography of muscle-attachments of nonlocals
individuals are different from locals foragers (migrants from neighboring farming communities?). These results demonstrate
the value of the Human Behavoral Ecology approach to our understanding of the broad process of human bio-cultural adaptations.