The Darwin-Eigen cycle is a theory proposed for abiogenesis, where selection for more greater fidelity acts as a positive feedback, increasing the size of the genome[1].
Introduction
editThe central tenet of Darwin's theory of natural selection[2] requires that for a population to evolve, there needs to be heredity, variation, and selection[2]. This is still true at the scale of self-replicating systems, whereby
The Eigen Threshold
edit!!This is copied verbatim!! If the product of the error (mutation) rate and the information capacity (genome size) is safely below one (i.e., less then one error per genome is expected to occur per replication cycle), most of the progeny will be exact copies of the parent, and reproduction of the system will be sustainable. If, in contrast, this value is significantly greater than one, most of the progeny will differ from the parent, and the system will not possess sufficiently faithful heredity to reproduce itself; in other words, a system whose fidelity drops below the Eigen threshold is headed for collapse resulting from an error catastrophe (a term and idea traceable to the early hypothesis of Orgel on the possible contribution of translation errors to aging [4]). It appears that the product of the replication fidelity and the genome size of modern life forms, from RNA viruses to complex eukaryotes, is, typically, close to the Eigen threshold, indicating that evolution solves an optimization problem with respect to replication fidelity, information content of the genome, and, possibly, variation (evolvability)
See also
editBibliography
edit- ^ Poole, A. (1999). "Early evolution: prokaryotes, the new kids on the block". BioEssays. 21 (10): 880–889. doi:10.1002/(SICI)1521-1878(199910)21:10<880::AID-BIES11>3.0.CO;2-P. PMID 10497339.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ a b Charles Darwin (1859). On the Origin of Species by Means of Natural Selection. London: John Murray. Cite error: The named reference "origin" was defined multiple times with different content (see the help page).