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bioRxiv · 10.64898/2026.04.07.717007

Generation-Establishment Tradeoffs Shape the Temporal Window of Recombinant Evolution

Anthony, S. J.·Wells, H. L.·Mitra, U.·Newton, P. K.
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Abstract

Recent viral coinfection experiments show that recombinant genomes are generated readily and depend strongly on infection timing and order, yet only a small fraction give rise to persistent lineages. We develop a hybrid deterministic-stochastic framework that resolves this discrepancy by coupling density-dependent recombinant generation with stochastic establishment of rare lineages. The resulting hazard of successful lineage formation is generically non-monotonic, increasing with parental abundance through enhanced generation while decreasing under competitive suppression, and exhibits a unique interior maximum in parental-density space. As parental populations evolve, their trajectory across this hazard landscape defines a sharply localized temporal window of evolutionary opportunity. These results reveal a general principle: evolutionary success is determined not only by intrinsic fitness, but by when variants arise within a dynamically changing ecological context.

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Anthony, S. J., Wells, H. L., Mitra, U., Newton, P. K.. 2026-04-09. Generation-Establishment Tradeoffs Shape the Temporal Window of Recombinant Evolution. https://doi.org/10.64898/2026.04.07.717007

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