Diachronie biology meets evo-devo: C. H. Waddington's approach to evolutionary developmental biology1

Abstract

SYNOPSIS. Conrad Hal Waddington (1905-1975) did not respect the traditional boundaries established between genetics, embryology, and evolutionary biology. Rather, he viewed them together as a "diachronic biology" In this diachronic biology, evolutionary change was caused by heritable alterations in development. Stabilizing selection within the embryo was followed by normative selection on the adult. To explain evolution, Waddington had to invent many concepts and terms, some of which have retained their usage and some of which have not. In this paper I seek to explicate Waddington's ideas and evaluate their usefulness for contemporary evolutionary developmental biology.