VOA慢速英语2021--研究:苏门答腊犀牛的好消息

Study: Good News About Sumatran Rhinos²

A genetic³ study of Sumatran rhinoceroses⁵ is providing what scientists call "good news" for the critically endangered animal. Experts say fewer than 100 of them remain in existence.

Researchers report that the two wild rhino¹ populations on the islands of Borneo and Sumatra showed unexpectedly good genetic health in a new study. The study also showed surprisingly low levels of inbreeding.

Inbreeding is the result of producing young from closely related parents.

The Sumatran rhinoceros⁴ is known for its two small horns and a thin coat of reddish-brown hair. It is the closest living relative to the wooly⁶ rhinoceros of the last Ice Age.

Nicolas Dussex helped lead the study that was published in Nature Communications.

"With such small population sizes, we were expecting much higher inbreeding," he said.

Dussex added that the findings suggest there may still be time to save the genetic diversity of the animal.

Researchers studied the genomes of seven rhinos from Borneo, eight from Sumatra and six from the former Malay Peninsula population.

The Sumatran rhinoceros is the smallest of the world's five rhinoceros species, weighing around 700 to 800 kilograms. The animal lives in rainforest areas. It also lives alone, except when mating and raising young. The animals once lived across a wide area of Southeast Asia, from the Himalayas to Borneo and Sumatra.

Illegal hunting, or poaching, and environmental destruction have hurt its population. The Sumatran rhinoceros population fell by about 70 percent over the past two decades.

Johanna von Seth was the study's lead author. She says genetic diversity is very important to the animal's long-term survival.

It permits, she said, "adaptation to future environmental changes and diseases." Adaptation means a change in an animal that makes it better able to live.

The researchers said steps such as moving rhinos for mating or using artificial insemination could cause an exchange of genes⁷ between the Borneo and Sumatra populations.

The Sumatran rhinoceros has shown low reproductive success in captivity⁸ and faces a high risk of inbreeding in the wild because of its small numbers.

Inbreeding creates a heightened risk of genetic problems. Scientists had feared that reports of health issues among these rhinos were evidence of a dangerously inbred population.

Love Dalén was a co-writer of the study.

"It's important to remember that the Sumatran rhino is still on the verge⁹ of extinction¹⁰ due to non-genetic factors," he said.

A factor is something that helps produce a result or effect.

Dalén said that the study showed that the species' genetics alone will not necessarily cause its extinction. But, problems from environmental destruction of its homelands and illegal hunting must be solved also, he said.

Words in This Story

species -- n. biology : a group of animals or plants that are similar and can produce young animals or plants : a group of related animals or plants that is smaller than a genus

captivity -- n. the state of being kept in a place (such as a prison or a cage) and not being able to leave or be free : the state or condition of being captive

artificial insemination – n. medical: a medical process in which semen is used to make a woman or female animal pregnant without sexual intercourse¹¹

on the verge of – expression at the point when (something) is about to happen or is very likely to happen

extinction -- n.the state or situation that results when something (such as a plant or animal species) has died out completely

1 rhino   

n.犀牛，钱, 现金

参考例句：

• The rhino charged headlong towards us.犀牛急速地向我们冲来。
• They have driven the rhino to the edge of extinction.他们已经令犀牛濒临灭绝。

2 rhinos   

n.犀牛（rhino的复数形式）

参考例句：

• There are many reports of people taming and even training Indian rhinos. 有许多关于人们驯养甚至训练印度犀牛的记载。 来自辞典例句
• The rhinos had fed during the night in the rice fields of these villagers. 犀牛夜里在这些村民的庄稼地里也已吃饱了。 来自辞典例句

3 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。

4 rhinoceros   

n.犀牛

参考例句：

• The rhinoceros has one horn on its nose.犀牛鼻子上有一个角。
• The body of the rhinoceros likes a cattle and the head likes a triangle.犀牛的形体像牛，头呈三角形。

5 rhinoceroses   

n.钱，钞票( rhino的名词复数 )；犀牛(=rhinoceros)；犀牛( rhinoceros的名词复数 )；脸皮和犀牛皮一样厚

参考例句：

• Rhinoceroses and dragons for once will let us walk in peace. 犀牛与龙安歇，让我们能平静地行走。 来自互联网
• Although the rhinoceroses are very heavy, they can run very fast. 犀牛虽然体型笨重，但仍能以相当快的速度行走或奔跑。 来自互联网

6 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。

7 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

8 captivity   

n.囚禁；被俘；束缚

参考例句：

• A zoo is a place where live animals are kept in captivity for the public to see.动物园是圈养动物以供公众观看的场所。
• He was held in captivity for three years.他被囚禁叁年。

9 verge   

n.边，边缘；v.接近，濒临

参考例句：

• The country's economy is on the verge of collapse.国家的经济已到了崩溃的边缘。
• She was on the verge of bursting into tears.她快要哭出来了。

10 extinction   

n.熄灭，消亡，消灭，灭绝，绝种

参考例句：

• The plant is now in danger of extinction.这种植物现在有绝种的危险。
• The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。

11 intercourse   

n.性交；交流，交往，交际

参考例句：

• The magazine becomes a cultural medium of intercourse between the two peoples.该杂志成为两民族间文化交流的媒介。
• There was close intercourse between them.他们过往很密。