The BABY PACE project (Biped and Autonomous: Bone microarchitecture of the Youngest, PAthological and Cultural Effects) aims to understand whether different cultural contexts, in both normal and pathological conditions of development, have an impact on the development of the trabecular and cortical bone during the acquisition of bipedal walking.
The combination of hereditary (genetics, sex, immunity) and environmental factors (e.g. geographic characteristics – altitude, rural locations, sun exposure –, socio-economic status in which a child develops, pathogen load) condition the development of a human being (size, rhythms, etc.). The importance of the influence of these many factors varies from a phase of development to another. Infancy, the first years after birth, is more sensitive to the environment. Thus, children living similar socio-economic, dietary, environmental contexts, tend to be the same size even with different genetic potentials. Infancy is a determinant period during which milestones leading to individual autonomy are acquired: weaning, language, continence, bipedal walking. The latter is typically acquired between 9 and 18 months around the world and cultural variations can be considered as an environmental factor influencing both its acquisition and maturation. BABY PACE focus to assess the roles of different environmental factors (e.g. socio-economic status, behavior, lifestyle) on normal and pathological skeletal development in children.
Cultural differences imply different social considerations of what a child is, as well as potentially providing insights into important social steps such as the age of beginning work, or transition to adulthood. Thus, the cultural definition of these milestones leads to variations in body, and so, in bone biomechanics. The cultural variations of the rhythm of the psychomotor development produce biomechanical differences. It is known since a long time that the bone microstructural organization responds to the variations in biomechanical constraints. Moreover, the bone microarchitecture is significantly more sensitive to environmental factors and may be more reflective of variation than the whole skeleton. As bioanthropologists only have access to skeletons to understand individual development in past populations, the analysis of bone microarchitecture is an innovative way of response.
BABY PACE hypothesizes that differences in developmental trajectories between cultural groups should be highlighted by variations in bone properties, reflective of disparate growth rhythms. bone biology as a cultural marker is a pioneering approach that will permit for the first time an understanding of ontogeny and childhood in the past which could allow interpretations about the place of children within their society, and aspects of funerary practices in cemeteries for future studies bases on BABY PACE results.
Bone microarchitecture is not only useful to bioarcheological questions but also to society and public health questions. More widely, historical sciences such as bioarcheology provide insights into the present and future. Thus, a good understanding of the factors influencing skeletal development will provide useful new data on the prevention of age-related bone loss in contemporary populations and many other public health issues.
