On Griffiths and Gray’s Concept of Expanded and Diffused Inheritance

Developmental Systems Theory is a theoretical reinterpretation of biological phenomena that challenges the conventional gene-centered account of development and evolution. In this article, I focus on Griffiths and Gray’s version of DST and particularly analyze their reconceptualization of inheritance. First, I present their concept of expanded and diffused inheritance; then, I examine and criticize their rejection of the multiple inheritance system model; finally, I present and oppose Griffiths and Gray’s extension of what they call the “causal parity thesis” from development to evolution. I argue that their proposal is an interesting and programmatic philosophical perspective on biological phenomena but fails to provide either additional heuristic tools for empirical investigation in biology or a more realistic representation of the biological world.