Scientists have discovered two [1] previously unknown ancestral "ghost" lineages that contributed genetic material to modern humans [1, 2].
This discovery alters the understanding of human evolution by proving that the ancestral tree is more complex than previously documented. By identifying these hidden lineages, researchers can better map how ancient populations interacted and migrated across the globe.
The findings resulted from a new DNA analysis method designed to uncover secrets about extinct ancestors [1]. This approach allows scientists to detect genetic signatures in living populations even when no physical fossils of the ancestor have been found. These lineages are termed "ghost" lineages because they exist only as genetic echoes within the genomes of current humans [1, 2].
Dr. Eske Sandsjö, the lead researcher, said the team was able to identify two [2] distinct lineages that contributed genetic material to the populations of Europe and Asia during the Late Pleistocene [2]. This period of the Pleistocene epoch is characterized by significant glacial activity and shifts in human migration patterns.
Researchers said the discovery highlights the interwoven nature of human history. The presence of these lineages suggests that modern humans encountered and interbred with more diverse groups of hominins than the well-known Neanderthals or Denisovans [1].
One researcher said this new method of analyzing modern humans’ DNA is revealing secrets about extinct ancestors [1]. The study indicates that these genetic contributions were not isolated incidents, but part of a broader pattern of prehistoric interaction [1].
Another researcher said these ghost lineages are a testament to the complex and interwoven history of human evolution [1]. The team continues to analyze genomic data to determine if other such lineages remain hidden in different global populations [1, 2].
““These ‘ghost’ lineages are a testament to the complex and interwoven history of human evolution,””
The identification of these ghost lineages suggests that the human family tree is far more branched than the traditional linear model. By finding DNA from ancestors for whom no fossil record exists, scientists are shifting the focus of paleoanthropology from physical remains to genomic data, potentially uncovering entire lost species through the biology of living people.
