Ancient stone tools found in China shake up human ancestor timeline (again)
Archaeologists have discovered ancient tools and bones in China that, once again, shake up the timeline of the human origin story. The items are more than two million years old, indicating that early hominins had spread much further east earlier than previously thought.
Although it's being updated all the time, the general consensus holds that hominins – the group of our ancestors that are more closely related to humans than to chimps – originated in Africa, before spreading out into Europe and Asia about 1.8 million years ago.
But more recent discoveries suggest our ancestors had packed their bags and left home way before then. A set of startlingly-human footprints found in the Greek islands date back some 5.7 million years, while 7-million-year-old bones found in Greece and Bulgaria are so old that it led researchers to wonder (somewhat controversially) whether humans and chimps actually split from their last common ancestor in Europe, not Africa.
Thankfully, the new find isn't quite so dramatic, but it's no less fascinating. At a maximum age of 2.12 million years, the recently-discovered artifacts are about 270,000 years older than bones and stone tools found in Dmanisi, Georgia, which are widely accepted to be the oldest remains of hominins beyond Africa. Not only that, they're much further from Africa than human ancestors were believed to have spread at that time.
The discovery was made in Shangchen on the Chinese Loess Plateau. Alongside animal bone fragments, the team found 80 stone tools, including a notch, scrapers, cobble, hammer stones and pointed pieces, which all showed clear signs of use. Most of them were made of quartz and quartzite that are believed to have come from the nearby Qinling Mountains.
Whoever left them behind weren't just passing through, either. These artifacts were found in 17 different layers of dust and fossil soil, deposited during different climates over the span of close to a million years, from 2.12 to 1.2 million years ago.
Although our history is literally set in stone, we wouldn't be surprised if future discoveries force us to continue editing the narrative.
The research was published in the journal Nature.
Source: Exeter University