ABSTRACT In the course of evolution organisms change both their morphology and their physiology in response to ever-changing environmental selection pressures. This process of adaptation leads to an “internalization,” in the sense that external regularities are in some way “imitated” by the living system. Countless examples illustrate the usefulness of this metaphor. However, if we concentrate too much on Shepard's “universal regularities in the world,” we run the risk of overlooking the many more fascinating evolutionary details which alone have made, and still make possible the evolution of diversity on earth. [Shepard]