Ancient skull pushes back Homo sapiens origins by 400,000 years, study says

An international team reported in Science that Yunxian 2, a fossil skull found in Hubei Province, China, is not Homo erectus and instead belongs to an early longi-related lineage linked to Denisovans, pushing the origin of Homo sapiens to more than one million years ago. The researchers say the finding indicates the human lineage split into distinct groups far earlier than previously believed, a conclusion that challenges the widely cited view that the Homo sapiens lineage began around 600,000 years ago. The team notes that the result, if confirmed, would rewrite much of the established timeline of human evolution and the geographic spread of early hominins across Asia and Africa. "This changes a lot of thinking because it suggests that by one million years ago, our ancestors had already split into distinct groups," said Chris Stringer, an anthropologist at the Natural History Museum in London. "Our research reveals that Yunxian 2 is not Homo erectus, but an early member of the longi clade and linked to the Denisovans," he added.

Yunxian 2 was discovered in 1990, badly crushed by excavators, and dated to roughly one million years ago. For years it was tentatively assigned to Homo erectus at the Yunxian site in central China. In the new study, researchers employed CT scanning, light imaging, and virtual reconstruction to produce a physical model of the skull as it would have appeared uncrushed. The reconstruction also incorporated small elements from Yunxian 1, another skull found at the site in 1989. The team then compared the Yunxian 2 model with 104 other fossil specimens and high-quality replicas to place it within the hominin family tree more accurately. The work was led by scientists from Fudan University, Shanghai, and the Chinese Academy of Sciences, Beijing, in collaboration with Stringer of the Natural History Museum.

The study’s findings describe a skull that carries a mosaic of traits. It retains some primitive features typical of Homo erectus, such as a large, squat braincase and a pronounced brow ridge, and a projecting lower face. Yet it also exhibits derived characteristics in the midface and posterior braincase and an overall brain size that appears larger than what is typically assigned to Homo erectus. Those patterns point toward affinity with the longi lineage, which includes Homo longi (Dragon Man) and, more broadly, connections to Denisovans. The authors emphasize that while Yunxian 2 shows some longi-like features, the authors are cautious about prematurely classifying it as Homo longi; they describe the skull as part of an early longi clade and say further data will be needed before a definitive taxonomic assignment is made.

The team’s principal conclusion, published in Science, is that Yunxian 2 is not Homo erectus but an early member of the longi clade and linked to the Denisovans. Stringer said, "This changes a lot of thinking because it suggests that by one million years ago, our ancestors had already split into distinct groups, pointing to a much earlier and more complex human evolutionary split than previously believed." Nevertheless, the researchers stopped short of naming Yunxian 2 as Homo longi for now, noting that additional data from a third skull found at Yunxian in 2022—Yunxian 3—will serve as an important test of the new reconstruction. They plan to extend their analyses to include more fossil material and other data sources to refine this new picture.

Beyond Yunxian 2, the paper’s authors outline a broader, updated framework for early human evolution in Asia. The Dragon Man lineage, previously identified from the Harbin cranium in northeastern China, is tied to a broader Asian longi lineage. The team emphasizes that this lineage may have arisen more than a million years ago, with later connections to Denisovans, a mysterious archaic group known from Siberia and parts of Asia. Denisovans themselves are a Denisovan DNA lineage that mixed with modern humans in different regions of Asia, leaving traces in the genomes of contemporary populations.

The researchers describe a radically different view of the human family tree: over the last 800,000 years, the major branches of large-brained hominins may trace to as few as five principal lines—Asian erectus, heidelbergensis, longi, sapiens, and neanderthalensis—and these groups were already diverging far earlier than previously recognized. The notion of a simple, linear progression from Africa to the rest of the world is replaced by a portrait of an intricate tapestry of migrations, replacements, and interbreeding among diverse hominins across continents.

Homo sapiens are thought to have evolved in Africa and began migrating out of the continent roughly 60,000 to 70,000 years ago, eventually reaching Europe and Asia. In these journeys, modern humans encountered Neanderthals (Homo neanderthalensis) and Denisovans, with interbreeding leaving genetic footprints in many populations today. Denisovan DNA, for instance, persists at notable levels in some Indigenous populations of Oceania and Asia, with recent research identifying distinct Denisovan ancestry in East Asia and Oceania that suggests multiple waves of contact between early humans and Denisovans.

The researchers behind the Yunxian 2 study stress that much remains to be learned about these early populations. The discovery highlights how Asia may have harbored multiple, interacting lineages long before modern humans left Africa in large numbers. It also underscores the value of integrating fossil evidence with advanced imaging and comparative anatomy to reconstruct a more nuanced history of our species’ origins. The authors plan to incorporate Yunxian 3 and additional fossils into ongoing analyses, a step they say will be critical for refining the timeline and relationships among early Homo species.

Overall, the study represents a significant pivot in the science of human origins. While it will take time for a consensus to emerge, the Yunxian 2 findings contribute to a growing view that the roots of humanity are deep, diverse, and more geographically widespread than once assumed. As researchers continue to uncover and analyze early skulls from Asia, they expect the picture of how our ancestors diverged and migrated to become increasingly complex—and increasingly informative about the deep, shared story of humanity.