RNA viruses: A bridge between life and artificial life

Abstract

RNA viruses can be an adequate bridge between life and artificial life. Under experimental conditions the parameters that in last instance are responsible for the evolution of replicons resembling primitive life forms can be easily studied. One year of a RNA virus evolving may be equivalent to one million years of an evolving DNA-based entity. High mutation rates as well as very short life cycles permit the capability of observing evolutionary effects in the lifetime of a human observer. Another important feature of RNA viruses, functionally related to its mutation rate, is the genome length, which ranges between 3 and 30 Kb, probably the shortest lengths with the highest estimated mutation rates that do not undergo error catastrophe when replicating. The evolutionary biology, that is to say the evolution of structural and functional properties, of RNA viruses can be probably simulated better than other non-RNA based life entities. The hypotheses underlying artificial life programmes could also be tested by experimental evolution of RNA viruses. Simplicity and rapid evolvability of RNA viruses are the basis for our proposal.