Equation 7 · Hominin Evolution and Deep Prehistory: A First-Principles Introduction
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where through are allele frequencies at site i in an outgroup, a candidate-admixed population, a comparison population without the admixture, and the archaic source, respectively. The estimator exploits a simple logic: if population has interbred with the archaic lineage and has not, should share systematically more rare variants with than does, in proportion to the fraction of its genome that traces to that admixture event. This is why admixture claims in the literature are reported as percentages with confidence intervals rather than as a binary yes/no — the estimate is statistical, built from many thousands of sites, not read off a single marker.
Sources cited in the article section
- [1] A Draft Sequence of the Neandertal Genome ↗
- [2] Genetic history of an archaic hominin group from Denisova Cave in Siberia ↗
- [7] Ancient Genomics of Modern Humans: The First Decade ↗
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