This is work with Jacques Rougemont (Geneva) and Tsvi Tlusty (Ulsan). The greater context is an attempt to bring the language of mathematics closer to that of biology, where there exist lots of data but few conceptual methods. Considering the evolution of functional proteins (which do something useful), we view them as amorphous solids. It turns out that describing the protein as a (finite) random network of connections, which are changed through evolution, a Green's function approach can explain many properties of proteins which biologists have observed. The talk needs no previous knowledge of biological concepts.