Ancient 'ghost' lineages embedded in every human genome, new study finds

A new method scans 500+ present‑day human genomes and reconstructs ancestral genealogies to reveal two previously unknown archaic lineages contributed to modern humans: a widespread 'ghost' lineage that left about 0.5%–1% of genomes in all people (likely from Homo heidelbergensis) and a 'super‑archaic' lineage dating to around 1.8 million years ago that is found in Oceanian genomes within Denisovan DNA at about 0.002%, implying interbreeding with extinct relatives far earlier in our history. The approach does not require fossil DNA and reinforces a view of human evolution as a web of repeated interbreeding rather than a simple branching tree. Published in Science (2026) by Moorjani and colleagues.