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The hypothesized dual roles of RNA as both information carrier and biocatalyst during the earliest stages of life require a combination of features: good templating ability (for replication) and stable folding (for ribozymes). However, this poses the following paradox: well-folded sequences are poor templates for copying, but poorly folded sequences are unlikely to be good ribozymes. Here, we describe a strategy to overcome this dilemma through G:U wobble pairing in RNA. Unlike Watson–Crick base pairs, wobble pairs contribute highly to the energetic stability of the folded structure of their sequence, but only slightly, if at all, to the stability of the folded reverse complement. Sequences in the RNA World might thereby combine stable folding of the ribozyme with an unstructured, reverse-complementary genome, resulting in a “division of labor” between the strands. We demonstrate this strategy using …