New Concepts for Dealing with the Evolution of Nucleic Acids

If we are asked where the transition from nonlife to life occurred, we must first refer to the conceptual level of DNA, of RNA, or of any of their self-replicating precursors. If we take any class of chemical compounds that are composed of a finite number of monomeric types, which we may call symbols, and if these symbols are lined up in linear sequences, thereby representing messages that can be "read" through specific interactions (i.e., complementary base pairing), then our class of compounds embodies a new property that goes beyond chemistry: This property is information. Such a quality can no longer be called typical for chemistry; it is characteristic of biology.