Figure 4.

Overview of the diversity protein materials found in nature, all made from the same building blocks (a library of about 20 amino acids) and forming functionally very different materials. The underlying concept is the universality-diversity-paradigm (UDP), which explains how different material properties can be achieved in spite of severe limitations in available energy, quality and quantity of a material’s basic elements (see, e.g. [19, 34] for further discussion).