Question

Explain the saying "ontogeny repeats phylogeny".

Answer 1

The phrase "Ontogeny recapitulates phylogeny" was coined by Ernst Haeckel. It states that the development of an organism (ontogeny) expresses evolutionary history and all the intermediate forms of its ancestors (phylogeny). Recapitulation means the development of an embryo followed the evolutionary history of organism. This is based on the comparative study of the embryos of related groups of animals.