Yet again, the history of the human family has been rewritten.
A new study has found that Homo erectus, one of the oldest human ancestors found outside of Africa, perhaps didn’t reach Southeast Asia until much more recently than previously thought.
Reporting in the journal Science, researchers argue that Homo erectus arrived in Java 1.3 to 1.5 million years ago, nearly 300,000 years later than previously believed. Importantly, this dating helps to dispel the controversial notion that Homo erectus originated in Asia. Although just a matter of a few hundred thousand years, this dating reaffirms that Homo erectus evolved in Africa.
At the archaeological site of Sangiran in Java, researchers have previously found 100 hominin fossils, belonging to at least three different species. Among those are a gang of Homo erectus fossils that are thought to be the oldest hominin fossils in Southeast Asia.
Homo erectus, which means "upright man," are the direct ancestors of several human species, including Neanderthals, Denisovans, and modern humans. Their arrival, sometime around 2 million years ago, marked the beginning of a bigger, faster, and smarter hominin lineage. They are also the longest-lived of all human species. It’s uncertain why they went extinct, but we know they roamed Earth for almost 2 million years right up until around 120,000 years ago.
The dating of Homo erectus’ arrival on the island of Java is important as it helps to piece together the complex puzzle of early hominin migrations out of Africa and across Eurasia. However, putting a date on the arrival to Sangiran has proved controversial, not least because of the area's complex volcanic geology.
For this new study, a team of Japanese anthropologists studied the volcanic material found below and within the layers where the hominin remains were discovered. Analysis of this sediment suggests that hominins arrived at the area much earlier than thought, most likely around 1.3 million years ago and no earlier than 1.5 million years ago. This means that Homo erectus’ dispersal across Asia took a lot longer than previously assumed.
Just last month, another piece of the Homo erectus puzzle was discovered when a study determined the age of the last known settlement of the species. Using a set of bones unearthed in the 1930s, the researchers argue that the last settlement of this species was at Ngandong, a site on the Indonesian island of Java, between 108,000 and 117,000 years ago, long after the arrival of modern humans to the area.