QUANTIFICATION OF THE MORPHOLOGICAL EVOLU TION OF THE HOMINID SKULL AND HETEROCHRONIES

Comparisons of adult skulls of various species of great apes, fossil h ominids and modern humans in the sagittal, Francfort and ortho-sagitta l planes reveal a series of three separate organisation plans: 'Great Ape', 'Australopithecine' and 'Homo', the latter including primitive m en (Homo ergaster-erectus-neandertalensis) and modern humans (Homo sap ients). Morphological changes between these plans are quantified for t he first time here by vector fields. This study confirms the existence of cranio-facial contraction, which occurs as a series of leaps. The juvenile morphology of the great ape skull is broadly preserved in adu lt Homo sapiens, suggesting that numerous heterochromies have occurred in mosaic during ontogeny (hypermorphosis, hypomorphosis, post-displa cements). (C) Academie des sciences/Elsevier, Paris.