A Nature paper published on 13 May reports that enamel proteins from six Chinese Homo erectus fossils are adding molecular evidence to the branching history behind human intelligence evolution, even if the study does not identify where intelligence itself came from.
The team analysed teeth from Zhoukoudian, Hexian and Sunjiadong in China, using ancient enamel proteins rather than DNA — which is usually long gone at this age — to place the fossils more precisely in the hominin family tree.
For years, the broad story of human origins was tidy enough for a textbook: Homo erectus spreads widely, later lineages branch off, and eventually the line leading to us acquires the cognitive traits bundled into human intelligence evolution. The new study keeps the fossils but makes the tree messier, which in this field is usually what better data does.
The Nature paper says the Chinese H. erectus record spans roughly 2.1 million to 1.6 million years ago and disappears around 0.4 million to 0.3 million years ago. One of the key specimens, a tooth labelled PA69 from Zhoukoudian, comes from layers dated to about 0.42 million years ago.
“Our study shows that paleoproteomics can provide molecular evidence for Middle Pleistocene hominins where ancient DNA is unavailable,” the authors wrote in the paper. That matters because enamel proteins survive where DNA often does not, giving researchers a way to test relationships that were previously argued mostly from skull shapes and jaw fragments.
Live Science reported that the results point to “deep genetic links” between H. erectus and modern humans, with the implications running through Denisovan-related ancestry. That does not mean these fossils reveal the origin of thought, language or planning. It means the ancestry of the populations that eventually produced those traits may have involved more overlap and more surviving branches than older linear models allowed.
The study looked at six individuals dated to about 400,000 years ago, drawn from three Chinese sites. The paper's contribution is partly technical: it combines fossil sampling with newer experimental and computational methods for reading ancient enamel proteins. In a field where the usual outcome is “the biomolecules are too degraded,” getting usable molecular data from this period is the interesting part.
An independent expert reaction in the available coverage was blunt. “It raises the question of whether we know what Homo erectus even is,” palaeoanthropologist John Hawks at the University of Wisconsin–Madison, who was not involved in the study, told Live Science. That is about taxonomy, but taxonomy is doing real work here: if the labels on these populations are fuzzier than scientists thought, then clean stories about the ancestry behind human intelligence evolution get fuzzier too.
Context from other recent fossil finds points in the same direction. Scientific American reported in January on 773,000-year-old Moroccan fossils that may sit near the ancestry of Homo sapiens, Neanderthals and Denisovans, while a Nature commentary argued those remains illuminate African ancestors of our species. The annoying habit of the evidence, if you like dry summaries, is that every new well-dated find seems to add another branch instead of removing one.
This was a protein study on a handful of fossils, not direct evidence about cognition, and the paper does not claim to explain intelligence.
The next milestone is likely more molecular sampling from additional Middle Pleistocene fossils, as researchers test whether enamel proteins can clarify where East Asian H. erectus fits relative to Denisovans and other archaic humans. The study appears in Nature as “Enamel proteins from six Homo erectus specimens across China.”
Key Takeaways
- A Nature paper published on 13 May 2026 analysed enamel proteins from six Homo erectus fossils in China.
- The fossils came from Zhoukoudian, Hexian and Sunjiadong, with one key Zhoukoudian tooth dated to about 0.42 million years ago.
- The study uses ancient enamel proteins because DNA usually does not survive in fossils this old.
- The findings complicate the hominin family tree linked to human intelligence evolution rather than directly explaining the origin of intelligence.
- Outside commentary says the results may blur the taxonomic boundaries around Homo erectus itself.
Further Reading
- Enamel proteins from six Homo erectus specimens across China — The primary Nature paper on ancient enamel proteins from Chinese H. erectus fossils.
- New analysis finds 'deep genetic links' between Homo erectus and modern humans — A reported summary of the study and its implications for hominin relationships.
- Fossil Discovery of New Human Ancestor May Connect Us to Neandertals and Denisovans — Context on another recent fossil find relevant to ancestry debates.
- Of all the quarries: Casablanca fossils reveal African ancestors of Homo sapiens — Nature commentary on the Casablanca fossils and their place in human origins research.
Originally published on novaknown.com
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