Scientists Find a Mysterious 'Ghost Lineage' In the DNA of West Africans| Ancient DNA| Ghost DNA

[08/06, 10:27 am] M Qamar Nazir: (Inside Science) — A mysterious extinct "ghost" human lineage that was an even more distant relation than Neanderthals may have interbred with the ancestors of modern West Africans, significantly contributing to their gene pool, a new study finds.
[08/06, 10:27 am] M Qamar Nazir: Some made their way out of Africa before we did, including the familiar Neanderthals in Eurasia and the newfound Denisovan lineages in Asia and Oceania.
[08/06, 10:29 am] M Qamar Nazir: Prior work estimated the ancestors of modern humans split about 700,000 years ago from the lineage that gave rise to Neanderthals and Denisovans, and the ancestors of Neanderthals and Denisovans diverged from one another about 400,000 years ago.
[08/06, 10:30 am] M Qamar Nazir: The story is a bit more tangled than the timeline suggests, as genetic analysis of fossils of these extinct lineages has revealed they once interbred with modern humans,
[08/06, 10:30 am] M Qamar Nazir: unions that may have endowed our lineage with helpful mutations as we began expanding across the world about 194,000 years ago.
[08/06, 10:30 am] M Qamar Nazir: Neanderthal DNA makes up roughly 1.8% to 2.6% of the genomes of modern humans from outside Africa, whereas Denisovan DNA makes up 4% to 6% of modern Melanesians.