Scientists solve mystery over copycat butterflies

 　　CANBERRA, Aug. 17 (Xinhua) -- Australian scientist on Wednesday said his international research team has discovered the trick on how butterfly learn to change its wing pattern to avoid being eaten by birds.

　　The Amazonian butterfly, Heliconius numata, has learnt to carry out a single genetic² switch to alter its wing pattern so it appears to be another bad-tasting butterfly that birds will avoid.

　　Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at Australia's University of Melbourne was part of the international research team, which was led by scientists at Centre National de la Recherche³ Scientifique (CNRS) and the University of Exeter in United Kingdom.

　　Dr. Lee said the historical mystery had puzzled researchers for decades.

　　"Charles Darwin was puzzled by how butterflies evolved such similar patterns of warning coloration," Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at the University of Melbourne told Western Australia Today.

　　"We have now solved this mystery, identifying the region of chromosome⁴ responsible for changing wing pattern."

　　He said the research team identified a genetic switch known as a supergene, which allowed the butterfly to morph into several different forms, allowing one species to mimic⁵ another.

　　"It is amazing that by changing just one small region of the chromosomes⁶, the butterfly is able to fool its predators⁷ by mimicking⁸ a range of different butterflies that taste bad," he said.

　　"The butterflies rearrange this supergene DNA⁹ like a small pack of cards, and the result is new wing patterns. It means that butterflies look completely different but have the same DNA.

　　"There are other butterflies doing similar tricks, but this is the most elegant one.

　　"I was just fascinated by how elegant they were."

　　He said the discovery proves that small chromosomal¹⁰ changes can preserve successful gene¹ combinations, and thus help a species to adapt.

　　The findings of the study are published on August 14 in the international journal Nature.

1 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

2 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

3 recherche   

adj.精选的；罕有的

参考例句：

• Applicants should have good PC skills with common office software,email and internet recherche.在办公软件、电子邮件、网络检索等个人电脑应用方面，申请人应具备良好的操作技能。
• The restaurant prides itself on its recherche menu.饭店以其精美的菜单自豪。

4 chromosome   

n.染色体

参考例句：

• Chromosome material with exhibits of such behaviour is called heterochromatin.表现这种现象的染色体物质叫做异染色质。
• A segment of the chromosome may become lost,resulting in a deletion.染色体的一个片段可能会丢失，结果产生染色体的缺失。

5 mimic   

v.模仿，戏弄；n.模仿他人言行的人

参考例句：

• A parrot can mimic a person's voice.鹦鹉能学人的声音。
• He used to mimic speech peculiarities of another.他过去总是模仿别人讲话的特点。

6 chromosomes   

n.染色体( chromosome的名词复数 )

参考例句：

• Chromosomes also determine the sex of animals. 染色体也决定动物的性别。 来自《简明英汉词典》
• Each of four chromosomes divide longitudinally. 四种染色体的每一种都沿着纵向分裂。 来自《现代汉英综合大词典》

7 predators   

n.食肉动物( predator的名词复数 )；奴役他人者（尤指在财务或性关系方面）

参考例句：

• birds and their earthbound predators 鸟和地面上捕食它们的动物
• The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》

8 mimicking   

v.（尤指为了逗乐而）模仿( mimic的现在分词 )；酷似

参考例句：

• She's always mimicking the teachers. 她总喜欢模仿老师的言谈举止。
• The boy made us all laugh by mimicking the teacher's voice. 这男孩模仿老师的声音，逗得我们大家都笑了。 来自辞典例句

9 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。

10 chromosomal   

adj.染色体的

参考例句：

• Like mRNA, both tRNA and rRNA are transcripts of chromosomal DNA. tRNA及rRNA同mRNA一样，都是染色体DNA的转录产物。 来自辞典例句
• In mammalian species, a variety of chromosomal rearrangements are known to exist. 在哺乳类的物种中，已知有许多类型的染色体内部重新排列。 来自辞典例句