About six million years ago, Sahelanthropus, one of our earliest human ancestors, may have swung down from a tree in Africa and started to walk upright. He had a smaller brain than we do, a flatter face and a heavy eyebrow ridge. In fact, he looked a bit like an ape, which is not surprising — humans descended from apes more than six million years ago.
Walking on two legs gave early humans lots of advantages over other animals. Standing upright made them taller, so they could see farther to look for food or spot danger. Having their arms free allowed them to carry things, use tools or fight.
As humans’ brains developed and grew bigger, our ancestors wanted to explore and see what was beyond the next hill. About 1.8 million years ago, some early humans began to leave Africa. They first traveled to Eurasia (now China and India). Later, about 800,000 years ago, humans arrived in Europe.
About 200,000 years ago, Homo sapiens — modern humans like us — evolved in Africa. They migrated to the Middle East around 125 000 years ago, then on to South Asia by 50,000 years ago. They also sailed to Australia around that time. About 40,000 years ago, Homo sapiens arrived in Europe, and in East Asia approximately 10,000 years after that.
No one knows for sure when humans traveled to North America. Sometime between 30 000 and 14 000 years ago, they likely sailed from Asia across the North Paci c. Then they continued down the west coast of North America and even as far south as South America
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