 Genetic causes can lead to physical causation and vice versa. Physical causation brings about genetic causation through mechanotransduction. Stretching, contraction, compression, fluid shear stress, and other physical dynamics are sensed by different molecular components inside and outside of cells that translate these environmental changes into biochemical signals (Hoffman et al. 2011; Wozniak and Chen 2009). Genetic causation brings about physical causation by creating different physical properties of cells and tissues through the presence, absence, or change in frequency of particular proteins. For example, different patterns of expression for cell adhesion molecules (e.g., cadherins) can lead to differential adhesion across epithelial sheets of tissue and thereby generate phase separations or compartments via surface tension variation (Newman and Bhat 2008). If these modes of causation are not competing, then how might one combine genetic and physical difference makers into an integrated causal explanation? How much explanatory unity can be achieved for this “reciprocal interplay”?