🌅 The “Ghost Ancestors” Hiding in Our DNA

SOURCE

Zhang et al. (2026)

WHAT TO KNOW

• Researchers at UC Berkeley developed a new technique to scan and compare human DNA, uncovering traces of two ancient hominin species hiding alongside the DNA of Neanderthals and Denisovans in the modern human genome. The researchers found one of these “ghost ancestors” interbred with Homo sapiens more than 50,000 years ago, contributing genes that today represent about 1% of the genomes of all modern humans. The other unidentified ancestor descended from a 1.8 million-year-old lineage and contributed genetic material indirectly via Denisovans—another one of our extinct relatives—more than 200,000 years ago.

WHY IT MATTERS

• H. sapiens, Neanderthals, and Denisovans all descended from a common ancestor in Africa, and all three hominin species once inhabited the Earth at the same time. Ancestors of modern humans diverged from the common lineage around 550,000 to 765,000 years ago, and when modern humans first migrated out of Africa some 50,000 years ago, they interbred with the two much older hominin lineages, (i.e., Neanderthals and Denisovans). Earlier work already suggested modern human genomes include genetic material beyond those two relatives, but the present study goes further by pinpointing where the contributions lie in our DNA and when their genetic material entered our own.

CONNECT THE DOTS

• Most living people of non-African ancestry inherited between 1% to 2% of their DNA from Neanderthals, while people from Asia and Oceania harbor roughly 0.1% to 6% Denisovan ancestry. Individuals from Asia and Oceania are the only populations alive today that are known to have substantial Denisovan DNA. A new study published to the bioRxiv preprint server suggests Denisovans may have towered over the other hominin species they lived alongside, potentially standing a foot taller and weighing 60 pounds heavier than Homo erectus. As a reminder, preprint studies are published prior to peer review.