Chromosome‑level ancestry reshapes pigmentation

Comparing pigmentation scores on classifier‑labelled chromosome tracts (e.g., WSH‑labelled vs non‑WSH) reveals that phenotype changes can occur within ancestral genomic segments rather than only by shifts in overall ancestry proportions. This means whole‑genome ancestry percentages can mislead when inferring where and when traits like pale skin evolved. — It implies that headlines linking modern traits to single ancient groups oversimplify history and that methodology (how you label tracts) can change historical claims with political and cultural consequences.