VOA科学技术2023--Scientists Recover Genetic RNA from Extinct Tasmanian Tiger

Scientists Recover Genetic² RNA from Extinct Tasmanian Tiger

Researchers say they have recovered genetic material from the Tasmanian tiger, an Australian animal that has long been extinct. The discovery could help scientists learn more about these creatures before they disappeared from Earth.

The recovered material is called ribonucleic acid, or RNA. RNA is a group of molecules³ present in all living cells that is important for genetic activity. It is similar to DNA⁴, the molecules that contain an organism's genetic instructions.

RNA carries genetic information it receives from DNA. RNA combines groups of proteins that organisms require to live and works to control cell metabolism⁵.

The researchers said the recovered RNA came from skin and muscle from the remains⁶ of a Tasmanian tiger stored since 1891 in a museum in Stockholm, Sweden.

Scientists have in recent years taken DNA from different ancient animals and plants. But the team said it was the first time RNA has been recovered from an extinct animal.

Scientists believe the Tasmanian tiger once lived on the Australian continent and surrounding islands. It was a top predator⁷ at the time, hunting kangaroos and other animals. The last known Tasmanian tiger is believed to have died in a Tasmanian zoo in 1936.

Emilio Mármol Sánchez is with the Centre for Palaeogenetics in Stockholm. He was the lead writer of a study describing the research results. The study recently appeared in the publication Genome Research.

Sánchez told Reuters news service RNA material gives scientists "a taste of the real biology" involving the cells and tissues of the Tasmanian tigers before they went extinct.

Marc Friedländer of Stockholm University was a co-writer of the study. He said, "If we want to understand extinct species, we need to understand what gene¹ complements⁹ they have and also what the genes¹⁰ were doing, and which were active."

Researchers have questioned how long RNA could survive at room temperature. The remains stored at the Swedish Natural History Museum were in a state of semi-mummification. This means skin, muscles and bones remained, but inside organs were lost.

"Most researchers thought that RNA would only survive for a very short time - like days or weeks - at room temperature," said evolutionary¹¹ geneticist Love Dalén. He is with the Centre for Palaeogenetics. Dalén added that while this might be the case when remains are wet, it does not appear to be so when they are dried.

The Tasmanian tiger looked similar to a wolf, except for the tiger-like lines appearing on its back. When people arrived in Australia about 50,000 years ago, large animal population losses followed. The arrival of European colonizers in the 18th century destroyed the remaining populations around the island of Tasmania.

Private "de-extinction" programs have been launched with the aim of bringing back some extinct animals. These include the Tasmanian tiger, flightless dodo bird and wooly¹² mammoth¹³.

However, many researchers have warned about the difficulties of using genetic processes to actually recreate an extinct species. While Sánchez of the Centre for Palaeogenetics said he too has concerns about such processes, he noted¹⁴ that he does "advocate for more research on the biology of these extinct animals."

Words in This Story

extinct – adj. not existing anymore

metabolism – n. all the chemical processes in the body, especially the ones that use food

predator – n. an animal that hunts and kills other animals for food

complement⁸ – n. something that makes something else seem good, appealing or complete

mummify – v. to preserve a dead body as a mummy: a dead body that is prevented from decaying by being treated with special substances before being covered in cloth

advocate – v. to publicly suggest or support an idea, development or way of doing something

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 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

4 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。

5 metabolism   

n.新陈代谢

参考例句：

• After years of dieting,Carol's metabolism was completely out of whack.经过数年的节食，卡罗尔的新陈代谢完全紊乱了。
• All living matter undergoes a process of metabolism.生物都有新陈代谢。

6 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

7 predator   

n.捕食其它动物的动物；捕食者

参考例句：

• The final part of this chapter was devoted to a brief summary of predator species.本章最后部分简要总结了食肉动物。
• Komodo dragon is the largest living lizard and a fearsome predator.科摩多龙是目前存在的最大蜥蜴，它是一种令人恐惧的捕食性动物。

8 complement   

n.补足物，船上的定员；补语；vt.补充，补足

参考例句：

• The two suggestions complement each other.这两条建议相互补充。
• They oppose each other also complement each other.它们相辅相成。

9 complements   

补充( complement的名词复数 )； 补足语； 补充物； 补集（数）

参考例句：

• His business skill complements her flair for design. 他的经营技巧和她的设计才能相辅相成。
• The isoseismal maps are valuable complements to the instrumental records. 等震线图是仪器记录有价值的补充资料。

10 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

11 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。

12 wooly   

adj.毛茸茸的；糊涂的

参考例句：

• I like the feel of this cloth and it has a warm wooly feel.我喜欢这块布的手感,它摸上去毛茸茸的很暖和。
• He wore a brown t-shirt with jeans and a pair of shoes,with a wooly hat covering his hair.小贝身穿一件棕色t恤，搭配牛仔裤和皮鞋，头戴一顶盖住头发的羊毛帽子。

13 mammoth   

n.长毛象；adj.长毛象似的，巨大的

参考例句：

• You can only undertake mammoth changes if the finances are there.资金到位的情况下方可进行重大变革。
• Building the new railroad will be a mammoth job.修建那条新铁路将是一项巨大工程。

14 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。