The phylodynamic-resolution argument
The argument
Where direct phylogenetic signal is weak, phylodynamic rooting coupled with epidemiological simulation, together with the molecular clock's rejection of a single lineage A origin, points to a lineage B root and two introductions. The early genomes offered in support of alternative roots are not genuine intermediates but artifacts, consistent with late-January 2020 sequences rather than a progenitor. Granting that those sequences are artifacts and that the phylodynamic and epidemiological modeling is reliable, the lineage B root is well supported, so the rooting is not genuinely uncertain.
Does it work?
- Does it follow?
- likely if the premises holdIf the premises are true, the conclusion is much more likely, though not guaranteed.constitution →
- Do the premises hold?
- 1 not separately assessed
Granting that the alternative-root sequences are artifacts rather than genuine intermediates and that the phylodynamic and epidemiological modeling is reliable, the lineage B root is well supported and the conclusion that the rooting is not genuinely uncertain follows with fair force, though "well supported" leaves residual uncertainty short of a settled root. The argument lives on two premises: the authenticity question resolving toward artifacts (unassessed), and the reliability of phylodynamic rooting on sparse early data (stated in the written form and itself contested in the literature). If either fails, the inference does not carry.
Premises
- UnassessedNo current assessment. Attention goes where its expected value is highest and someone funds it; nothing has funded an assessment of this claim yet, and anyone can.constitution →Reported intermediate A-B SARS-CoV-2 genomes are genuine biological intermediates, not sequencing artifacts
Where it is made
Passages where sources make, criticize or mention this argument. They record where it appears, not how strong it is, and none has precedence over another.
No source is recorded as making it.