Oldest Stone Tools Outside Africa Unearthed in China

[Judi Lynn]

Six artifacts date to 2.1 million years ago, potentially rewriting what we know about which species led the migration out of Africa



(Zhu et. al./Nature)

By Jason Daley
smithsonian.com
July 12, 2018

Throughout the 20th century, the widely accepted story of humanity’s migration from Africa began with a human ancestor called Homo erectus, a relatively big-brained, tall species of hominin that began to venture all across Asia more than a million years ago. But in recent decades, new evidence has begun to punch holes in that timeline. Now, reports Carl Zimmer at The New York Times, new stone tools unearthed in China indicate someone made it 8,000 miles from Africa to east Asia as far back as 2.12 million years ago, and that someone probably wasn’t Homo erectus.

Zimmer reports that back in 1964, researchers found the skull of a Homo erectus in the Lantian area of the Shaanxi province, which at the time they placed at around 1.15 million years. When researchers revisited the Lantian site in the early 2000s, however, they determined that the layer the skull came from was older—about 1.63 million years old. They also noticed what appeared to be stone tools embedded 200 feet up in a cliff face.

That observation led to 13 years of painstaking excavations. During that time, the team found that various human ancestors occupied the site in Shangchen’s southern Chinese Loess Plateau between 1.26 and 2.12 million years ago. According to their study, published in the journal Nature, the researchers uncovered 80 stone artifacts found in 11 layers of soil deposited when the climate was warm and wet. They also uncovered 16 artifacts in six layers that date to a time when the climate conditions were colder and drier.

Most importantly, they were able to date the layers of soil using a technique called paleomagnetism by looking at certain minerals which align with the Earth’s magnetic field, which occasionally flip flops. The oldest artifacts were found in a layer sandwiched between rock formed 2.14 million years ago and 1.85 million years ago. Based on their position, the researchers estimate six of the tools are 2.12 million years old, making them the oldest stone tools found outside Africa.

More:
https://www.smithsonianmag.com/smart-news/oldest-stone-tools-outside-africa-unearthed-china-180969621/