字幕表 動画を再生する 英語字幕をプリント Every person living on earth today belongs to the same species: Homo sapiens. And humans worldwide have always been curious about our origins. <phrases in other languages> "Where do we come from?" We can now trace our origins back at least six million years to Africa, where the earliest humans evolved. Several early human species emerged there, and survived in a variety of environments and climates before evolving into new species or going extinct. About two million years ago some populations of early humans began to spread beyond Africa. Over hundreds of thousands of years populations moved into Asia where they faced the challenges of yet new environments and climates. New species continued to evolve, and eventually go extinct. Then about two hundred thousand years ago, a new species evolved in Africa. These were the first modern humans, the first members of our own species, the ancestors of every human being alive today. We can all trace our DNA back to these African origins. Over time populations of Homo sapiens spread throughout Africa into Europe and western Asia. In some of these places early human species lived on the verge of extinction. This journey of Homo sapiens began during challenging times. There were extreme droughts and monsoons in Africa, and other environmental upsets there and in Asia. At one point our species' population was reduced to no more than 10,000 adults. We nearly became extinct. But we are an adaptable species. Our ability to use our human traits to meet new challenges enabled us to survive. While earlier human species became extinct, modern humans continued to spread around the world. By about 17,000 years ago, Homo sapiens was not only a worldwide species, we were the sole surviving human species. We left behind a trail of fossils, evidence of our epic worldwide journey. Like some earlier humans, we evolved differences in skin color and hair texture as we adapted to different environments. But these differences are only skin deep. They follow along the continuum and do not separate modern humans into the categories some people call "races." The DNA of all modern humans is 99.9% identical. You are part of this six million year story of adaption and survival. It is written in the language of your genes, in every cell of your body. With the billions of other humans living today, you can say, <phrases in other languages> "We are all one species."
B1 中級 人間の起源。一つの種、世界に生きる (Human Origins: One Species, Living Worldwide) 1217 77 Mark Lin に公開 2021 年 01 月 14 日 シェア シェア 保存 報告 動画の中の単語