Caterpillars had, after years of trial and error, managed to biologically engineer a plant which produced artificial diamond, which was widely used industrially, as the one covalent bond leading from the edge allowed a truly mono-molecular blade. Glass had not been developed in the caterpillar world, as they did not have sufficient silicon to form glass, but the early development of polymers did allow plastic windows that were as tough as glass without being brittle.
Copyright 1999 Ian Rennie, for Remiel Productions.