Dietary effects on development of the human mandibular corpus.

摘要: The extent to which the mandibular corpus exhibits developmental plasticity has important implications for interpreting variation in adult and juvenile morphology archaeological paleontological record. Here, we examine ontogenetic changes breadth, rigidity, strength two population samples with contrasting diets: late prehistoric Tigara from Point Hope, Alaska, characterized by a very demanding masticatory regime, proto-historic Arikara Sully Site South Dakota, less regime. A total of 52 11 Tigara, 32 10 were included study. Juveniles ranged age 1 17 years, good representation younger (1-6-year-old) juveniles (20 Arikara, 18 Tigara). Superoinferior buccolingual external cortical bone breadths mandibles measured at Pm(4) -M(1) M(1) -M(2) junctions using calipers biplanar radiographs, respectively. An asymmetrical hollow beam model was employed reconstruct cross sections calculate bending rigidities strengths sagittal transverse planes. Among adults, have greater width, strength, ratios dimensions than Arikara. This shape difference develops gradually during growth, only weak trends among young juveniles, increasing near-adult contrasts adolescents. These results support role functional mechanical loading mandible growth producing differences morphology.