Haeckel and levels of development

Abstract

This paper differentiates between four levels of behavioural development (according to Schmidt, 1972): phylogeny, anthropogeny, ontogeny and actualgeny. This categorization helps to provide an understanding of multidisciplinary developmental science. Haeckel’s recapitulation theory states that ontogeny recapitulates phylogeny, linking evolution theory and ontogeny. However, Haeckel’s depictions of embryonal phases, which were intended to prove that phylogeny is repeated during embryonal development, are not tenable—at least not in the sense that he proposed, namely, that phylogeny is the mechanical cause of ontogeny. Accusations of fraud concerning Haeckel’s depictions and others are discussed and given a nuanced reading. However, the conclusion must still be that Haeckel’s recapitulation theory is not tenable The theory was, however, the main catalyst behind the creation of developmental psychology as an academic discipline. Haeckel and his recapitulation theory are clearly present in the works of founding fathers such as Hall, Baldwin and Piaget. It is not an exaggeration to state that developmental psychology could not have come into existence without it. Recapitulation theory connected developmental psychology with biology and the observation methods leading to baby biographies; and it offered an excuse for the gentlemen who conducted research in the nineteenth century to study children: for the children were the source of learning about phylogeny and evolution. Nowadays recapitulation theory does not play a role in developmental science. Comparisons of levels of behavioural development mainly take place for heuristic reasons, as in the ethology-developmental psychology relationship (De Waal, 1982, 2005, 2013).