古代石器工具揭示275萬年前早期人類的卓越發明才能！

A recent discovery in northwest Kenya is changing what scientists know about the earliest humans. At an archaeological site called Namorotukunan, researchers found stone tools that were used by primitive humans as far back as 2. 75 million years ago. These tools, which look like ordinary rocks, were actually made with great skill and precision. The most surprising part of the discovery is that these early humans used stone tools continuously for about 300,000 years. Before this, experts believed that early tool use was random and short-lived, but the evidence from Namorotukunan shows that the knowledge of making tools was passed down through many generations.

Professor David Braun from George Washington University led the research team. He said that this discovery provides strong evidence for a major change in our understanding of human evolution. The tools found at the site were so sharp that researchers could cut their fingers on them. Over ten years, archaeologists uncovered 1,300 artifacts, including sharp flakes, hammerstones, and stone cores. These were made using a technique called Oldowan, which is known as the first widespread method of making stone tools. The same types of tools were found in three different layers of the site, with each layer representing a different period in time. The deeper the layer, the older the tools. Many of the stones were carefully chosen for their quality, showing that the toolmakers were skilled and knew exactly what they needed.

The landscape around Namorotukunan changed dramatically over time, shifting from lush wetlands to dry grasslands and even semideserts. Normally, animals would have to adapt to these changes by evolving or moving away. However, the people living in the region managed to survive by using technology instead of changing their bodies. They used stone tools to find food, such as cutting open animal carcasses and digging up plants. Evidence at the site shows that animal bones were broken and cut with these tools, meaning that meat was a consistent source of food. The technology allowed these early humans to access different types of food as the environment changed. The people living at Namorotukunan had relatively small brains and lived alongside other early humans called australopithecines, who had larger teeth and a mix of chimpanzee and human traits. This finding challenges the idea that continuous tool use only began much later, when humans had evolved larger brains. Professor Braun explained that the tools at Namorotukunan were used before the increase in brain size, suggesting that early humans were more inventive and adaptable than previously thought. The ability to use technology to survive in changing environments can now be traced back to 2. 75 million years ago, and possibly even earlier.