The received model of evolution sees all inherited features resulting from deterministic networks of interacting genes, implying that living systems are reducible to information in genetic programs. The model requires these programs and their associated phenotypes to have evolved by an isotropic search process occurring in gradual steps with no preferred morphological outcomes. The alternative is to recognize that clusters and aggregates of cells, the raw material of evolution, constitute middle-scale material systems. This implies the necessity of bringing the modern physics of mesoscale matter into the explanatory framework for the evolution of development. The relevant, often nonlinear, physical processes were mobilized at the inception of the phyla when their signature morphological outcomes first appeared and remain as efficient causes, albeit transformed, in present-day embryos. This physicogenetic perspective reengages with concepts of saltation, orthogenesis, and environment-induced plasticity long excluded from evolutionary theory.
