ABSTRACT
Not that a biological optical system is beyond the pale of the physical scientist or engineer. But, for a beginning, the materials employed by nature, although in general characterizable in terms of the physical parameters customary in man-made optics, differ in many ways from those familiar to the scientist. This has to do mainly with their provenance. They don't come from the smelting oven, nor have they even grown in the manner of crystals. They are assembled from the ultimate recipe, the DNA of the genome, using organic molecules. Yet they have ordinary optical properties, such as a refractive index that varies in an unsurprising manner with wavelength. The significant property, which is commonly taken for granted but should be a never-ending source of wonder, is transparency.
