Editing Openai/686aedb2-60b0-8003-98a8-e1766cf496a6 (section)

=== Assistant:  ===
===== The mathematics they deploy =====
Wills & Carter translate the familiar “error-threshold” logic of quasispecies theory into coupled differential equations for three, inter-dependent processes:
# template replication,
# amino-acid assignment (charging tRNAs), and
# protein synthesis.

Key expressions (their Eqs. 24, 28–29) show that if a less-accurate protein catalyst (either an aaRS or a replicase) appears in a ribozyme-only system, the overall accuracy

p=qr−f(εu−εr)p = q_r - f(\varepsilon_u-\varepsilon_r)p=qr−f(εu−εr)
falls immediately because εᵤ > εᵣ. Even a small protein contribution (fraction f ≪ 1) drags the entire system below the error threshold, collapsing both replication and translation fountains of information. In every hybrid regime they analyse, the ribozyme world is dynamically unstable once proteins join the party Wills+Carter17

.

Wide-margin or close call?
Because the dependence on f is linear and the accuracy gap (εᵤ–εᵣ) can be orders of magnitude for proto-enzymes, the distance to the threshold is not a near thing. A few per-cent participation by sloppy protein catalysts suffices to wreck the coding system. The authors therefore describe the RNA-coding-world as facing “insuperable problems” and conclude that the takeover “appears to be impossible, rendering the notion of an RNA Coding World scientifically superfluous” Wills+Carter17

. In short, it is a wide-margin failure.

Do they hedge?
They acknowledge their model is deliberately minimalist (well-mixed chemistry, clockwork ribosome, no explicit compartmentalisation) and thus could be refined. Yet they argue these omissions would, if anything, tighten the error constraints, not loosen them. No point in the paper hints that new data are likely to overturn the verdict; the strongest “qualification” is a call for future spatial or compartment models to verify the same instability Wills+Carter17

.

===== - Core idea – Genetic coding began in an autocatalytic partnership between short peptides and RNA (a “peptide·RNA world”): very small peptides already carried rudiments of aaRS-like specificity; in turn, RNA templates allowed them to be reproduced. This mutual “reflexivity” let translation fidelity and replication fidelity impedance-match from the outset — something impossible, they argue, for a pure RNA world Wills+Carter17 . =====
* What’s new vs. older peptide-RNA suggestions? - Earlier models (e.g., Cairns-Smith crystals, early co-evolution concepts) posited peptides as generic helpers. Wills & Carter specify which peptides — ancestral Class I/II aaRS fragments — and show mathematically how their activities close the feedback loop that stabilises coding. - They integrate recent structural evidence that these two aaRS classes arose from complementary strands of the same gene, naturally implementing a binary (2-letter) primordial code that can expand hierarchically. - The emphasis on impedance matching between replication and translation is unique to their framework and is central to their claim that coding had to start with peptide participation, not add peptides later.

===== - Peer-reviewed rebuttals specifically targeting their differential-equation analysis have not (yet) appeared in the literature up to mid-2025. Their follow-up papers in Molecular Biology & Evolution (2018) and IJMS (2020) extend, rather than retract, the framework and have met mostly with interest, not demolition. =====
* Skeptical commentary does exist. Journalistic pieces (e.g., Quanta Magazine) note that the PRCW evidence is “purely computational” and stress that the RNA world still enjoys far more experimental support; several origin-of-life researchers quoted there regard any claim of formal falsification as premature quantamagazine.org<ref>{{cite web|title=quantamagazine.org|url=https://www.quantamagazine.org/the-end-of-the-rna-world-is-near-biochemists-argue-20171219/|publisher=quantamagazine.org|access-date=2025-11-16}}</ref>.
* Mainstream origin-of-life reviews since 2018 (e.g., “The difficult case of an RNA-only origin of life”, 2019) cite Wills & Carter as part of a growing peptide-RNA camp but treat their verdict as one hypothesis among several, not a settled matter. None mounts a point-by-point mathematical refutation.

===== Wills & Carter’s falsification rests on robust, threshold-type equations: even tiny error mismatches doom an RNA-only coding world, so the verdict is not a hair-split. =====
They express little doubt that further data will reverse it; instead they invite others to refine the mathematics under more realistic geochemical settings.
Their Peptide-RNA Coding World goes beyond generic “peptides-first” ideas by rooting coding in aaRS precursors and reflexive feedback, a step change from earlier co-evolution notions.
To date, the community has questioned the sufficiency of their evidence but has not dismantled the math; the debate continues, with many writers urging caution before declaring the RNA world dead.