Experimentally replicated blade tools produced with heat treated silcrete. Some of these tools may have been mounted unto a wood handle to create a tool with disposable blades, as pictured above. Credit: © Science/AAAS
From Live Science:
Early humans crossed a threshold around 75,000 years ago, when they started painting symbols, carving patterns and making jewelry. A new study found they also began to use fire to make tools around that time.
Until now, this complex, multi-step process for tool making was only known to occur as recently as 25,000 years ago in Europe. But the new findings show this breakthrough occurred much earlier, and in Africa, not Europe.
By heating up stones in a fire before chipping away at them to make blades, early humans could make tools sharper and produce them more efficiently.
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