SSS 2012-02-28
时间：2018-12-24 作者：英语课 分类：Scientific American(二)月
英语课
This is Scientific Ameican 60 second Science, I'm Cynthia Graber, this will just take a minute!
Cave painting connects us with our prehistoric 1 artist ancestors. But there's a dearth 2 of such illustration in the Americas. Now a cave in Brazil has been found to house the oldest New World image known.
The shelter was excavated 3 from 2002 to 2009. In the last days there, scientists exposed a foot-high figure in the bedrock. It has a c-shaped head, two outstretched arms, two legs, and a very visible penis.
Using radiocarbon dating, the researchers dated an ash layer to between 9300 and 10,500 years ago. A hearth 4 found about an inch above the drawing gives similar results. And the researchers used a technique called optically stimulated 5 luminescence on sediment 6, which also dated to around 10-12,000 years ago.
The scientists say this makes the petroglyph the oldest reliably dated cave art in the Americas. The research was published in journal Public Library of Science One.
Echoes of this style exist in other early art in the region, amidst diverse styles throughout North and South America. The researchers the range of images reveals a spectrum 7 of symbolic 8 thought dating back to early in the history of human colonization 9 of the hemisphere.
Thanks for the minute, for Scientific American 60 second Science, I'm Cynthia Graber
1 prehistoric
adj.（有记载的）历史以前的，史前的，古老的
- They have found prehistoric remains.他们发现了史前遗迹。
- It was rather like an exhibition of prehistoric electronic equipment.这儿倒像是在展览古老的电子设备。
2 dearth
n.缺乏，粮食不足，饥谨
- There is a dearth of good children's plays.目前缺少优秀的儿童剧。
- Many people in that country died because of dearth of food.那个国家有许多人因为缺少粮食而死。
3 excavated
v.挖掘( excavate的过去式和过去分词 )；开凿；挖出；发掘
- The site has been excavated by archaeologists. 这个遗址已被考古学家发掘出来。
- The archaeologists excavated an ancient fortress. 考古学家们发掘出一个古堡。 来自《简明英汉词典》
4 hearth
n.壁炉炉床，壁炉地面
- She came and sat in a chair before the hearth.她走过来，在炉子前面的椅子上坐下。
- She comes to the hearth,and switches on the electric light there.她走到壁炉那里，打开电灯。
5 stimulated
a.刺激的
- The exhibition has stimulated interest in her work. 展览增进了人们对她作品的兴趣。
- The award has stimulated her into working still harder. 奖金促使她更加努力地工作。
6 sediment
n.沉淀，沉渣，沉积(物)
- The sediment settled and the water was clear.杂质沉淀后，水变清了。
- Sediment begins to choke the channel's opening.沉积物开始淤塞河道口。
7 spectrum
n.谱，光谱，频谱；范围，幅度，系列
- This is a kind of atomic spectrum.这是一种原子光谱。
- We have known much of the constitution of the solar spectrum.关于太阳光谱的构成，我们已了解不少。
8 symbolic
adj.象征性的，符号的，象征主义的
- It is symbolic of the fighting spirit of modern womanhood.它象征着现代妇女的战斗精神。
- The Christian ceremony of baptism is a symbolic act.基督教的洗礼仪式是一种象征性的做法。
9 colonization
殖民地的开拓，殖民，殖民地化； 移殖
- Colonization took place during the Habsburg dynasty. 开拓殖民地在哈布斯堡王朝就进行过。
- These countries took part in the colonization of Africa. 这些国家参与非洲殖民地的开发。