Homo erectus, a hominin species that originated in equatorial Africa or the Caucasus region of Eurasia, arrived on the island of Java in Indonesia around 1.3 million years ago — 300,000 years later than previously thought, according to an analysis of zircon grains in tuffs from the archaeological site of Sangiran.
The World Heritage archaeological site of Sangiran in Central Java is widely regarded as one of the most important sites in understanding the evolution of our early ancestors and their slow march across the globe.
It has produced a steady stream of Homo erectus finds since 1936, now totaling over 100 specimens.
However, despite decades of research, the chronology of the Sangiran site remains uncertain and controversial, particularly the timing of Homo erectus’ first appearance in the region.
To solve this long-standing chronological controversy, Dr. Shuji Matsu’ura from Japan’s National Museum of Nature and Science and colleagues used a combination of fission-track and Uranium/Lead (U/Pb) dating to determine the age of zircon grains found above, below and within the hominin-bearing layers of the Sangiran fossil deposit.
They found that the first appearance date for the Sangiran hominins is most likely 1.3 million years ago and less than 1.5 million years ago.
“Concerning the first appearance date of Homo erectus in the Sangiran area, our results provide a probable date of 1.3 million years ago and a maximum possible date of 1.45 million years ago,” the researchers said.
“Another hominin specimen that has been contended to be the earliest Javanese Homo erectus is the Mojokerto skull from the Perning site in East Java,” they added.
“This skull is now concluded to be less than 1.49 million years old.”
“Thus, the hominin dispersal into Java is resolved to be less than 1.5 million years ago.”
The findings were published in the January 10 issue of the journal Science.