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A human skull unearthed in central China and dated to around 1mn years ago could overturn prevailing assumptions about the origins of Homo sapiens and the timeline of human evolution the BBC reports.
The fossil, known as Yunxian 2, was originally thought to belong to Homo erectus, the first species of humans to develop larger brains. Fresh analysis by Chinese authorities, however, indicates it is closer to Homo longi, a sister lineage of both Neanderthals and modern humans.
If correct, this would place the emergence of Homo sapiens at least 500,000 years earlier than the current consensus, extending the period of co-existence between major human species.
Questions are bound to be raised though, and with China having in recent years made at least half a dozen claims on much more recent historical 'events' that have little to no archaeological evidence to back them, this will in some circles be seen as Beijing looking to compete with Africa as the traditional starting point of human civilisation.
The findings for now at least rely on a combination of morphological study and genetic modelling. Both approaches suggest that large-brained humans were diversifying far earlier than previously assumed. This interpretation would mean that early representatives of Homo sapiens including Neanderthals and Homo longi may have walked the Earth together almost 1mn years ago, potentially interacting and interbreeding over a prolonged span of evolutionary history.
Such a shift would, the BBC report adds, help explain the long-standing confusion over a number of fossils dated between 800,000 and 100,000 years ago that have thus far resisted clear classification into one camp or the other. As such, The re-dating of Yunxian 2 offers a framework in which these remains could be organised into branches of three closely related lineages, alongside their more primitive ancestors in Asia and Europe.
The work is based on three skulls excavated in Hubei Province in central China. The specimens had been crushed and distorted, complicating earlier assessments. Researchers, however, managed to reconstruct their original form using digital scanning and computer modelling, enabling a more accurate comparison with other hominin species.
If validated, the conclusions would imply that Homo sapiens did not arise solely in Africa 300,000 years ago, as has long been assumed, but had already begun to take shape much earlier and possibly across a wider geographical area. The Chinese findings mean that the presence of million-year-old fossils in both Africa and Europe leave the precise origin of those early humans unresolved.
Given other recent claims on as of yet unproven historical ‘facts’ by Beijing though, the study is only likely to add fuel to a debate in a field where disagreements are routine.
Digital reconstruction reveals Yunxian 2 crania as early member of Homo longi
Summary author: Walter Beckwith
A digital reconstruction of the nearly one-million-year-old Yunxian 2 cranium from China, which corrected previous distortions inherent in the fossil, suggests it belonged to the Asian Homo longi clade. This means the cranium represents an early branch of the sister lineage to modern humans that may have included the enigmatic Denisovans.
Fossil evidence shows that, during the Middle Pleistocene, multiple Homo lineages with diverse physical forms coexisted. Much of what is known about human evolution and archaic hominins relies on fossil skulls. Yet many specimens from this era are damaged and/or deformed, leading to uncertainties concerning species interpretations. For example, the Yunxian crania from China date back nearly a million years and exhibit a mosaic of primitive traits resembling Homo erectus alongside features suggestive of later species, such as Homo sapiens. However, because one of these skulls, Yunxian 2, was highly distorted, its evolutionary position has long been uncertain. Using advanced CT scanning and digital reconstruction techniques, Xiaobo Feng and colleagues corrected the compression and distortions in the Yunxian 2 crania. According to Feng et al., phylogenetic analyses incorporating the reconstructed Yunxian 2 crania revealed a mix of previously unknown primitive and derived traits, suggesting that the fossil belongs to the Asian H. longi clade – a sister group to Homo sapiens, which likely included the Denisovans. Individuals within the H. longi clade exhibit distinctive traits, including a larger braincase, narrower spacing between the eyes, a more pronounced glabellar depression, and a lower, elongated frontal bone, which are characteristics clearly visible in the Yunxian 2 fossil. The authors also show that Yunxian fossils are likely the oldest within the longi clade, though not the most basal. Given the fossil’s blend of primitive traits from earlier humans and more derived features shared with H. longi and H. sapiens, Feng et al. suggest that the Yunxian group may represent a transitional form, capturing an early phase of rapid diversification within these lineages.
Journal
Science
Article Title
The phylogenetic position of the Yunxian cranium elucidates the origin of Homo longi and the Denisovans
Article Publication Date
25-Sep-2025
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