Getting Past the RNA World: The Initial Darwinian Ancestor

A little-noted result of the confirmation of multiple premises of the RNA-world hypothesis is that we now know something about the dawn organisms that followed the origin of life, perhaps over 4 billion years ago. We are therefore in an improved position to reason about the biota just before RNA times, during the era of the first replicators, the first Darwinian creatures on Earth. An RNA congener still prominent in modern biology is a plausible descendent of these first replicators. Outline 1 Introduction 2 A new vantage 3 Evidence for ancient RNA 4 Conservation and persistence 5 Persistence of CHNOPS 6 Persistence of RNA 7 The hypothesis 8 Earlier ideas about nucleotide cofactors 9 Pre-RNA world credentials 10 An old variant backbone 11 An augmented alphabet, an augmented manifold of reactions 12 Chickens and eggs 13 Continuity with an RNA world 14 Novel replication chemistry 15 Catch-22