A taxonomy of biological information

Reproduction, and thus information transfer across generations, is the most essential process of life, yet biologists lack a consensus on terms to define biological information. Unfortunately, multiple definitions of the same terms and other disagreements have long inhibited the development of a general frarmwork for integrating the various categories of biological information. Currently, the only consensus is over two general categories, genetic information, which is encoded in DNA, and non-genetic information, which is extracted from the environment. Non-genetic information is the key to understanding gene-environment interactions and is the raw material of Fields such as developmental plasticity, behavoir, communication, social learning and Cultural evolution. In effect, differences in information possessed by individuals produce phenotypic variation. We thus define biological information as 'factors that can affect the phenotype in ways that may influence Fitness'. This definition encompasses all information that is potentially relevant to organisms, which includes the physical environment. Biological information can be acquired passively from genes or via processes Such as epigenetics, parental effects and habitat inheritance, or actively by organisms sensing facts about their environment. The confusion over definitions mainly concerns non-genetic information, which takes many more forms than genetic information. Much of the confusion derives from definitions based on how information is used rather than on the facts from which it is extracted. We recognize that a fact becomes information once it is detected. Information can thus be viewed analogously to energy in being either potential or realized. Another Source of confusion is in the use of words outside their usual meanings. We therefore present intuitive definitions and classify them according to categories of facts in a hierarchical framework. Clarifying these concepts and terms may help researchers to manipulate facts, allowing a fuller study of biological information.