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This is Scientific American's 60-Second Science, I’m Steve Mirsky. Got a minute?

Biologists often attempt to construct a genealogy¹ that shows the relationships of all life on earth. One well-accepted effort compares the nucleic acid sequences that code for ribosomal RNA and a few proteins in many different organisms. The result shows clear groupings. The bacteria cluster together, the eukaryotes—that’s you and frogs and maple² trees—all go together. And archae, a distinct kind of single cell, go together. A few years ago, researcher Song Yang decided³ to look at similarly shaped regions of proteins in various organisms. Yang’s mentor⁴, Russell Doolittle, discussed the work at an evolutionary⁵ biology conference on May 1st at Rockefeller University in New York City. Yang compared the DNA⁶ sequences of the similarly shaped protein sections. The resulting map of relationships almost completely matched the one made from different data sources. Which is good confirmation⁷ that the genealogy of life on earth is indeed what researchers thought it was.

Thanks for the minute for Scientific American's 60-Second Science. I'm Steve Mirsky.

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1 genealogy
n.家系，宗谱
参考例句：
He had sat and repeated his family's genealogy to her,twenty minutes of nonstop names.他坐下又给她细数了一遍他家族的家谱，20分钟内说出了一连串的名字。 He was proficient in all questions of genealogy.他非常精通所有家谱的问题。

2 maple
n.槭树，枫树，槭木
参考例句：
Maple sugar is made from the sap of maple trees.枫糖是由枫树的树液制成的。 The maple leaves are tinge with autumn red.枫叶染上了秋天的红色。

3 decided
adj.决定了的，坚决的；明显的，明确的
参考例句：
This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。 There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。

4 mentor
n.指导者，良师益友；v.指导
参考例句：
He fed on the great ideas of his mentor.他以他导师的伟大思想为支撑。 He had mentored scores of younger doctors.他指导过许多更年轻的医生。

5 evolutionary
adj.进化的；演化的，演变的；[生]进化论的
参考例句：
Life has its own evolutionary process.生命有其自身的进化过程。 These are fascinating questions to be resolved by the evolutionary studies of plants.这些十分吸引人的问题将在研究植物进化过程中得以解决。

6 DNA
(缩)deoxyribonucleic acid 脱氧核糖核酸
参考例句：
DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。 Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

7 confirmation
n.证实，确认，批准
参考例句：
We are waiting for confirmation of the news.我们正在等待证实那个消息。 We need confirmation in writing before we can send your order out.给你们发送订购的货物之前，我们需要书面确认。