In Time magazine 1993 there was an intriguing little article with the title “Copying What Comes Naturally”.1It concerns the efforts of American scientists to produce new materials by imitating the design of biologically manufactured substances. For example, by studying the silk produced by species of spiders called golden orb weavers it is hoped to manufacture silk that is light, strong, stretchy and as tough as Kevlar (the stuff used to make bulletproof vests). We must all have been impressed by the speed with which a spider’s web is made, and its effectiveness in enabling spiders to capture insects for their food. To produce Kevlar, vats of concentrated sulphuric acid maintained at high pressure are necessary. But spiders produce silk in the open air using water as a solvent, and at a very fast rate.
There are many other materials that scientists would like to be able to copy and produce. How do horses’ hooves remain so crack-resistant? What is the adhesive which mussels and barnacles secrete, fastening them so securely to surfaces? What makes rats’ teeth so sharp, and an insect’s cuticle hard? How is it that the rhinoceros’s horn is capable of self-healing any tiny cracks that arise after jousting matches with other rhinos?
Many of the answers to these questions lie in an understanding of protein structures, since most of the desirable substances are natural proteins. A small company in California called Protein Polymer Technologies is already producing protein-based coatings, based on a hybrid between silkworm protein and fibronectin, a blood protein promoting cell adhesion. This material is painted onto plastic sheets for growing cells in the laboratory. The company is hoping to produce another coating that gives a cheap polyester the luxurious feel of silk.
Another application of these biomimetic materials is in increasing the body’s tolerance to implanted devices like artificial hearts and pacemakers. A protein called elastin can be made chemically, or, as scientists hope in the future, by using genetically engineered bacteria which will be able to produce the protein cheaply on a large scale.
Another protein which may be of value is called resilin, a springy protein found on the cuticle of cockroaches and other insects. Unlike synthetic rubber, which swells on contact with organic solvents, resilin remains unchanged, and would thus be a very useful material to make gloves for handling fuels and other solvents.
Natural materials are usually superior to those which are man-made, as every parent whose children possess wooden and plastic toys soon discovers. Even in its sin-stricken state, God’s creation is superior to the creations of man. And man looks to copy ‘nature’, as he calls it, for improving the materials and substances he uses in everyday life. All God’s works praise Him as the all-wise and understanding fashioner of all things. May the day come soon when men will gladly acknowledge that wisdom and understanding, and use their skills and inventiveness in ways that glorify their Maker.
The Origin of the Organic World – Part One