The RNA-First Fallacy: Conflating Evolutionary Ancestry with Prebiotic Primacy.

The RNA-World hypothesis remains the most widely accepted framework in origins-of-life research, anchored in compelling biochemical evidence for RNA's deep evolutionary ancestry. However, this viewpoint routinely extends beyond that and is frequently conflated with claims that RNA served as life's primal substrate. This essay argues that the RNA-First paradigm, in its pursuit of this claim, systematically projects biological biases onto a chaotic and combinatorially vast abiotic landscape. It relies on privileged, highly complex molecular constructs whose spontaneous emergence in such combinatorial settings is overwhelmingly implausible. Critically, the experimental evidence accumulated in support of RNA-First has largely demonstrated the compatibility of RNA with prebiotic conditions, but not its probability, necessity, or chemical precedence over the numerous alternatives that abiotic chemistry affords. The eventual emergence of RNA chemistry demands a preceding protobiological stage, characterized by chemically diverse, collectively autocatalytic molecular networks. Embracing this broader protobiological framework, and confronting the true combinatorial complexity of abiotic chemistry, is essential for a rigorous and unbiased account of life's origin.