Ontogeny is embryonic history whereas phylogeny. is evolutionary history. The recapitulation theory was postulated by Haeckel (a German biologist). According to this theory the organism repeats its phylogeny during embryonic development. Lamarck wrote a book Philosophic Zoologique on organic evolution. The basis of this theory was inheritance of acquired characters. Darwin proposed theory of natural selection and survival of the fittest and wrote the book origin of species. Weismann proposed theory of germplasm.