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EVOLUTION
In his Theory of Economic Development (1), the economist Joseph Schumpeter distinguished between inventions-the creation and establishment of something new-and innovations, inventions that become economically successful and earn profits. In this distinction, Schumpeter echoes an earlier dichotomy in biology between the physical sources of genetic and phenotypic variability among organisms and those factors leading to the establishment (fixation) of a favored variant within a population. Schumpeter's definition of invention intentionally includes fixation, and thereby highlights the elusive nature of innovation with its connotation of influence and success.
The theoretical foundations of evolutionary invention and innovation were discussed at a recent workshop at the Santa Fe Institute (2). The meeting brought together biologists, paleontologists, technologists, and economists to consider the nature of evolutionary novelty and the similarities and differences between biological and technological invention and innovation.
Case studies of invention and innovation abound from the Cambrian radiation of animals in biology to the telegraph, telephone, and Internet in technology, and some are sufficiently beguiling to obscure an evident lack of generality. Three explanations for the absence of robust, general theories of invention and innovation emerged at the meeting. First, "innovation" and "novelty" are two of the most overused and misunderstood words in evolutionary biology. For example, some meeting participants defined novelty as rare morphological transitions that result from breaching genetic or morphological constraints, exemplified by a developmental mutation in the Yucca moth that gave rise to a new antennal limb (3). Others defined novelty as changes that have important consequences for the environment, the classic example being the origin of oxygen-dependent photosynthesis that led to an oxygenated atmosphere. Still others defined novelty as changes resulting in the generation of abundant taxonomic diversity, such as the cichlid fishes of East African lakes or the diversification of flowering plants. Second, scale is a problem: morphological innovations in the fruit fly Drosophila challenge developmental biologists studying mutations in homeobox genes that affect embryonic development (Nipam Patel, University of California, Berkeley). Yet mutations in homeobox genes and associated morphological changes may be dismissed as unimportant by paleobiologists interested in larger scale changes. Finally, many discussions ignore the distinctions made by Darwin and Schumpeter between invention as origin and fixation, and innovation as consequence and success.
In biology, invention...