BANGKOK: A digital reconstruction of a million-year-old skull indicates humans may have diverged from ancient ancestors 400,000 years earlier than previously believed and possibly in Asia rather than Africa.
These findings stem from the reconstruction of a crushed skull discovered in China in 1990, potentially resolving the longstanding “Muddle in the Middle” period of human evolution.
Experts not involved in the research cautioned that the findings are likely to be disputed, highlighting ongoing uncertainties within the human evolutionary timeline.
The skull, labelled Yunxian 2, was originally thought to belong to the human forerunner Homo erectus.
Modern reconstruction technologies revealed features more closely aligned with species believed to have existed later, including Homo longi and our own Homo sapiens.
“This changes a lot of thinking,“ said Chris Stringer, an anthropologist at London’s Natural History Museum who participated in the research team.
He added that the discovery suggests our ancestors had already split into distinct groups one million years ago, indicating a much earlier and more complex evolutionary split.
If confirmed, the findings imply there could have been much earlier members of other early hominins, including Neanderthals and Homo sapiens.
The research also challenges the longstanding assumption that early humans dispersed exclusively from Africa, according to Michael Petraglia from Griffith University’s Australian Research Centre for Human Evolution.
Petraglia noted that east Asia may have played a very key role in hominin evolution, representing a potential big change in understanding.
Published in the journal Science, the study used advanced CT scanning and virtual reconstruction techniques to model the complete Yunxian 2 skull.
Scientists partially relied on another similar skull to shape their model before comparing it to over 100 other specimens.
The resulting model displays a distinctive combination of traits, with some features similar to Homo erectus and others, like larger brain capacity, closer to later species.
Stringer explained that Yunxian 2 may help resolve the confusing array of human fossils from between one million and 300,000 years ago.
Much about human evolution remains debated, with Petraglia describing the study’s findings as provocative though grounded in solid work.
Andy Herries, an archaeologist at La Trobe University, expressed skepticism, noting that fossil morphology is not always a perfect indicator for human evolution based on genetic analysis.
Herries stated that the interpretation does not fully account for the known genetic histories of these species.
These findings represent the latest in a series of recent research complicating our understanding of human origins.
Homo longi, or “Dragon Man”, was only identified as a new species and close human relative in 2021 by a team including Stringer.
The authors emphasised that fossils like Yunxian 2 demonstrate how much remains to be learned about our origins. – AFP