Researchers Announce Discovery of Early Human Ancestor
A group of scientists announced Thursday what they say is the discovery of remains from an early ancestor of human beings.
Bones from the species were found two years ago inside a cave at a United Nations World Heritage Site, near Johannesburg, South Africa. The South African government has named the area the “Cradle of Humankind” because of its rich collection of ancient human-like remains.
The scientists are calling the new species, ‘Homo naledi. The word naledi means “star” in South Africa’s Sesotho language.
The scientists reported that about 1,500 bones have been recovered from the cave. They said the bones come from at least 15 individuals. The team reported its findings in the journal eLIFE.
Lead scientist Lee Berger works at the University of Witwatersrand. He said the discovery “was right under our nose in the most explored valley of the continent of Africa.” Mr. Berger spoke to reporters Thursday in Johannesburg.
“This is a great moment for us. It is a moment that was perhaps two years in the making. For some of you who may follow our adventures since November of 2013. But in fact, it is 90 years in the making: 90 years of exploration here in South Africa for human origins.”
The scientists said the newly discovered species ‘Homo naledi’ probably stood up straight when walking. They said a normal adult stood about 1.5 meters tall and weighed about 45 kilograms.
The researchers described the hands and feet of the new species as human-like. But they said the ribs, shoulders and pelvis were closer to other early ancestors than to those of modern humans.
The Associated Press reported that Mr. Berger said his team is not claiming that Homo naledi was a direct ancestor of modern-day people.
The researchers believe neledi developed between 2.5 million and 2.8 million years ago, but the bones might be younger than that. The team said dating the bones is one of their projects.
Also unclear is why the bones were in a hard-to-reach part of the cave in the first place. Scientists wondered whether others could have placed dead bodies there in a kind of behavior rarely found in early humans.
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1.The researchers described the hands and feet of the new species as human-like. But they said the ribs, shoulders and pelvis were closer to other early ancestors than to those of modern humans.
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2.Also unclear is why the bones were in a hard-to-reach part of the cave in the first place. Scientists wondered whether others could have placed dead bodies there in a kind of behavior rarely found in early humans.
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两年前，科学家们是在位于南非约翰内斯堡附近一个联合国世界遗址的洞穴里发现这种物种的骨化石的 。因该地区拥有丰富的古人类骨化石，因此南非政府将该地区命名为“人类摇篮”，科学家们将此发现的新物种命名为“智人之星”，Naledi这个单词在南非塞索托语中意为“明星” 。
科学家称，从该洞穴中复原出大约1500块骨化石 。他们还表示，这些骨化石至少来自于15个人 。研究人员在“eLIFE”杂志上发表了他们这一发现 。
领导这个小组的是威特沃特斯兰德大学的美国古人类研究学家李·伯杰 。伯杰先生于周四在约翰内斯堡接受采访时表示“这一伟大的发现正是位于非洲大陆考察次数最多的山谷中，可以说是在我们的眼皮底下发现的 。”
“这是一个伟大的时刻，是历经两年多不懈努力才换来的 。可能有些人认为我们是从2013年11月才开始这项研究的，但实际上却历经了90年，我们在南非这个地方对人类起源进行探索已长达90年 。”
研究人员相信“智人之星”大约在250到280万年前出现，但是这次发现的骨化石可能属于更晚时期的 。该研究小组还表示，接下来确定骨化石的年龄是他们的工作内容之一 。
然而，尚未清楚的是这些骨化石为什么最初是在该洞穴难以到达的位置被发现的 。科学家们猜测是不是其他人将遗体安放在此处，这种行为在早期人类活动中是很少见的 。