 There is a very important class of exceptions to this general abandonment of the replicator question. Developmental Systems Theory was formulated as a radical alternative to the interactor/replicator dichotomy (Oyama 1985; Griffiths &amp; Gray 1994, 1997; Oyama, Griffiths, &amp; Gray 2001). Here the evolving unit is understood to be the developing system as a whole, privileging neither the replicator nor the interactor.