Cryo-microscopy reveals nano-sized copy machine implicated in origin of life

How the intricate molecular machinery of life arose from simple beginnings has been a long-standing question. Several lines of evidence point towards a primordial "RNA world," where an "RNA copy machine" (a so-called replicase) started making copies of itself and other RNA molecules to kick-start evolution and life itself. However, the ancient replicase appears to have been lost in time and its role in modern biology has been taken over by more efficient protein machines.