A 300,000-year-old skull found in China is unlike any previous human skull seen before.

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that Relic skull Dating back 300,000 years, it is unlike any other human fossil found before the modern era, which could point to a new branch in the human family tree, according to new research.

An international team of researchers from China, Spain and the United Kingdom discovered the skull – specifically the mandible, or mandible – in the Hualongdong region of eastern China in 2015, along with 15 other specimens, all of which are believed to have originated from Late Middle Pleistocene a period.

Scientists believe that the late middle Pleistocene, which began about 300,000 years ago, was a pivotal period for the evolution of hominins — species considered human or closely related — including modern humans.

Posted in Journal of Human Evolution On July 31, a study by the research team found that the mandible, known as HLD 6, is “unexpected” and does not fit into any existing taxonomic groups.

According to the study, many Pleistocene fossils of hominins unearthed in China were also difficult to classify and were previously seen as anomalies. However, this discovery, along with other recent research, is slowly changing what people know about the evolutionary pattern of the late Middle Pleistocene.

By comparing the HLD 6 mandible to those of Pleistocene hominins and modern humans, the researchers found that it had features of both.

It is shaped similarly to the lower jaw of Homo sapiens, our modern human species that evolved from Homo erectus. But it also shares the characteristics of another branch that evolved from Homo erectus, Denisovans. Like Denisovans, HLD 6 doesn’t seem to have a chin.

“HLD6 does not represent a true chin but has some weakly expressed traits that seem to predict this typical feature of Homo sapiens,” said study author María Martinón Torres, director of the National Center for Research on Human Evolution (CENIEH) in Spain.

“Hualongdong is one of the first known fossil groups in Asia to present this mosaic of primitive and Homo sapiens-like features,” she added.

The researchers hypothesized that HLD 6 must belong to a taxon that has not yet been given a name, and that modern human characteristics could have been present as early as 300,000 years ago – before modern humans appeared in East Asia.

The researchers also took into account the age of the individual the jawbone came from, as skull shapes can vary between children and adults.

HLD 6 is thought to belong to children between the ages of 12 and 13. While the researchers did not have an adult skull of the same species to compare against, they looked at the skulls of middle and late Pleistocene hominins of similar and large ages and found that their shape patterns remained consistent regardless of age, further supporting the scientists’ theory.

According to Martinón-Torres, more work is needed to properly position HLD 6.

“More excavations and studies are necessary to understand its exact location in the human family tree,” she said.