The simple emergence of complex molecular function

At odds with a traditional view of molecular evolution that seeks a descent-with-modification relationship between functional sequences, new functions can emerge de novo with relative ease. At early times of molecular evolution, random polymers could have sufficed for the appearance of incipient chemical activity, while the cellular environment harbours a myriad of proto-functional molecules. The emergence of function is facilitated by several mechanisms intrinsic to molecular organization, such as redundant mapping of sequences into structures, phenotypic plasticity, modularity or cooperative associations between genomic sequences. It is the availability of niches in the molecular ecology that filters new potentially functional proposals. New phenotypes and subsequent levels of molecular complexity could be attained through combinatorial explorations of currently available molecular variants. Natural selection does the rest.This article is part of the theme issue 'Emergent phenomena in complex physical and socio-technical systems: from cells to societies'.

Automated summary

Contrary to the traditional view of molecular evolution, new functions can emerge de novo. Random polymers could have been sufficient for the appearance of initial chemical activity in the early stages of molecular evolution, while the cellular environment contains numerous proto-functional molecules. The emergence of function is facilitated by intrinsic mechanisms in molecular organization such as redundant mapping of sequences into structures, phenotypic plasticity, modularity, and cooperative associations between genomic sequences. The availability of niches in the molecular ecology filters new potentially functional proposals. New phenotypes and higher levels of molecular complexity can be achieved through combinatorial explorations of currently available molecular variants, with natural selection playing its role.