A. Céphalopodes - 1. Ammonites oxfordiennes.

18 pages

: Quantification of the morphological evolution of the Hominid skull and heterochronies

Comparisons of adult skulls of various species of great apes, fossil hominids and modem humans in the sagittal, Francfort and ortho-sagittal planes reveal a series of three separate organisation plans: 'GreatApe', 'Australopithecine'and 'Homo', tbe latter including primitive men (Homo ergaster-erectus-neandertalensis) and modern humans (Homo sapiens). Morphological changes between these plans are quantified for the 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 adult Homo sapiens, suggesting that numerous heterochronies have occurred in…

Chromosomes and the origins of Apes and Australopithecines

International audience; Comparison of molecular data suggests that the higher apes (Gorilla, Pan) and humankind (Homo) are closely related and that they diverged from the common ancestor through two speciation events situated very closely together in time. Examination of the chromosomal formulas of the living species reveals a paradox on the distribution of mutated chromosomes which can only be re-solved by a model of trichotomic diversification. This new model of divergence from the common ancestor is characterized by the transition from (1) a monotypic phase to (2) a polytypic phase of three sub-species - pre-gorilla, pre-chimpanzee and pre-australopithecine. The quadruped ancestors of Au…

Global changes recorded in the Oxfordian Ammonite associations

Les Cardioceratinae, des " monstres prometteurs "

National audience

Éloge d'Henri Tintant (1918-2002) : l'homme et le scientifique.

20 pages