ABSTRACT
We derive a stability criterion, analogous to Eigen’s replication error threshold, for the information carrying capacity of a collectively autocatalytic set of polymers. We consider a specific system comprised of polymer molecules in which certain general ligation (and cleavage) reactions occur. We describe the physical constraints that must be fulfilled for the system to be capable of increasing in functional complexity as a result of progressive dynamic selection. These constraints relate to the embedding of catalytic functions in the space of possible polymer structures as dictated by the laws of physics and chemistry. Functional complexity is defined in terms of the degree of catalytic specificity displayed by the population of molecules in the system. Our results are likely to find application in the study of catalytic nucleic acids and peptides and should help to clarify how the differentiated roles of information carriers (nucleic 614acids) and functional catalysts (proteins) emerged in prebiotic molecular biology.
