PortugaL

Project Description.

Our species, Homo sapiens, has a small and gracile face that grows and develops differently when compared to other fossil human species. Such morphological features accentuate throughout the evolution of H. sapiens and the transition from hunting-gathering to agro-pastoralism was decisive for the gracilization of the skull. This change in mode of subsistence was a long-term process that marks the transition from pre-Neolithic hunting-gathering to Neolithic/post-Neolithic agro-pastoralism. It has been identified as the most significant socio-cultural and biological transition in H. sapiens, and it is associated with profound dietary changes. Such changes include the adoption of domesticated plants and softening of food also due to processing prior to ingestion. This caused an increase in, e.g., oral pathogens and, because bone adapts to mechanical loading, changes in skull form. The cranium became generally smaller and more gracile and the mandible generally shorter and wider.

Despite studies showing how this dietary shift impacted skull form, no research has yet examined how it impacted mandibular growth and development. This is crucial because mandibular form relates to diet better than cranial form, and because malocclusion and dental crowding increased during and after this transition. Thus, it is critical to understand the impact of this dietary transition on mandibular growth and development. Interestingly, multiple studies have shown inter-population differences in cranial growth and development within modern humans and such differences have been related to, e.g., masticatory function. Thus, this project will assess how the dietary transition from pre-Neolithic hunting-gathering to Neolithic/post-Neolithic agro-pastoralism impacted mandibular growth and development and, hence, if pre-Neolithic and Neolithic/post-Neolithic mandibles grow and develop differently. To provide a global rather than a local scale, it will use samples from different geographical areas.