title: Bit by bit: the Darwinian basis of life.
abstract: All known examples of life belong to the same biology, but there is increasing enthusiasm among astronomers, astrobiologists, and synthetic biologists that other forms of life may soon be discovered or synthesized. This enthusiasm should be tempered by the fact that the probability for life to originate is not known. As a guiding principle in parsing potential examples of alternative life, one should ask: How many heritable "bits" of information are involved, and where did they come from? A genetic system that contains more bits than the number that were required to initiate its operation might reasonably be considered a new form of life.
authors.affiliation: Department of Molecular Biology, Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California, United States of America. gjoyce@scripps.edu
authors.forename: Gerald F
authors.initials: GF
authors.lastname: Joyce
mesh_terms: D001419:Bacteria / Q000737:chemistry / Q000145:classification / Q000235:genetics; D005075:Biological Evolution; D004247:DNA / Q000737:chemistry / Q000235:genetics; D018534:Earth, Planet; D056084:Genetic Fitness; D000069497:Origin of Life; D010802:Phylogeny; D011336:Probability; D012313:RNA / Q000737:chemistry* / Q000235:genetics; D054679:Ribosome Subunits, Small / Q000737:chemistry / Q000145:classification / Q000235:genetics; D012641:Selection, Genetic
chemical_list: D012313:RNA; D004247:DNA