When a cell divides, its DNA’s operational instructions are copied by RNA (ribonucleic acid), which directs the proteins that build cell machinery. The current leading origin of life hypothesis, RNA world (or RNA first) offers a limited and researchable claim, first proposed in 1967 by Carl Woese, Leslie Orgel, and Francis Crick: that RNA preceded and stood in for DNA in ancient life. Because this route slightly reduces the awesome complexity, it was not only too good to be false, it was hailed by key researchers as “the molecular biologist’s dream.” By 1986, biochemist (and Nobelist) Walter Gilbert envisioned a whole RNA “world” and Leslie Orgel was almost certain it had existed.

Not everyone was or is “almost certain.” Gustavo Caetano-Anollés is convinced of the opposite because “That world of nucleic acids could not have existed if not tethered to proteins.” A. G. Cairns-Smith, admittedly a champion of a rival “clay origin” theory, labeled it “absurd to imagine,” complaining that there are “14 major chemical/molecular hurdles” against more primitive nucleotides like RNA. New York University chemist Robert Shapiro (1935-2011) compared the theory’s likelihood to “a gorilla composing, in English, a coherent recipe for the preparation of chili con carne” and pleaded for greater realism. Yes, RNA theorists admit, there are difficulties. More.