VOA科学技术2024--Corals May Have Been First Glow-in-the-Dark Animals

A new study suggests ancient corals found deep in the ocean were the first animals to glow in the dark. To glow means to shine a steady light.

Many animals, insects and sea life have the ability to glow. But a study from biologists based in the United States suggests corals started glowing 540 million years ago.

Andrea Quattrini is curator of corals at the Smithsonian Museum of Natural History in Washington, D.C. She was one of the writers of the study. Quattrini said the ability to light up helps creatures living in the deep-sea to communicate.

"It's very important in deep waters," Quattrini said.

The new study recently appeared in the publication Proceedings¹ of the Royal Society B.

Scientists know about many ocean animals that light up, including fish, squid, octopus², jellyfish and even sharks. The ability to glow is called bioluminescence, it comes from a chemical reaction.

Some animals use the light as protection. Others use it to find a mate.

Steven Haddock is another study co-writer. He is a marine³ biologist at the Monterey Bay Aquarium⁴ Research Institute in California. He explained that scientists used a paintbrush attached to an underwater vehicle to lightly touch the luminous⁵ coral. Haddock said the coral, when touched, begins to glow pink, orange, white, blue and purple.

Danielle DeLeo is another study co-writer and a marine biologist at the Smithsonian. She said in some kinds of coral, the whole body glows. In others, "only parts of their branches will glow," she said.

Scientists do not fully⁶ know the function of the glowing for coral. They do not know if it is meant to attract or keep away certain organisms, or possibly both. But DeLeo said the fact that corals light up so often means that the glowing serves a critical function.

It is one thing to try to learn about why the corals light up. But how did the researchers determine that coral had been glowing for over 500 million years?

To answer the question, the scientists built a family tree using genetic⁷ data from 185 species of glowing coral. They decided⁸ the common ancestor of all the glowing coral lived 540 million years ago and could glow just like the current coral.

Before this research, marine scientists believed the earliest example of a glowing sea creature was a shrimp⁹ that lived about 270 million years ago.

Coming up with an age of the earliest glowing coral helps add more information to the timeline of the development of life on Earth. The oldest glowing coral is now placed in the time of the Cambrian explosion, when life on Earth developed quickly.

Words in This Story

curator -n. a person who watches over something or keeps things in order

branch -n. the part of a plant or tree growing off the main stalk or trunk

determine -v. to think about something in order to reach a conclusion

1 proceedings   

n.进程，过程，议程；诉讼(程序)；公报

参考例句：

• He was released on bail pending committal proceedings. 他交保获释正在候审。
• to initiate legal proceedings against sb 对某人提起诉讼

2 octopus   

n.章鱼

参考例句：

• He experienced nausea after eating octopus.吃了章鱼后他感到恶心。
• One octopus has eight tentacles.一条章鱼有八根触角。

3 marine   

adj.海的；海生的；航海的；海事的；n.水兵

参考例句：

• Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
• When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。

4 aquarium   

n.水族馆，养鱼池，玻璃缸

参考例句：

• The first time I saw seals was in an aquarium.我第一次看见海豹是在水族馆里。
• I'm going to the aquarium with my parents this Sunday.这个星期天，我要和父母一起到水族馆去。

5 luminous   

adj.发光的，发亮的；光明的；明白易懂的；有启发的

参考例句：

• There are luminous knobs on all the doors in my house.我家所有门上都安有夜光把手。
• Most clocks and watches in this shop are in luminous paint.这家商店出售的大多数钟表都涂了发光漆。

6 fully   

adv.完全地，全部地，彻底地；充分地

参考例句：

• The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气，然后全部呼出。
• They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。

7 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。

8 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。

9 shrimp   

n.虾，小虾；矮小的人

参考例句：

• When the shrimp farm is built it will block the stream.一旦养虾场建起来，将会截断这条河流。
• When it comes to seafood,I like shrimp the best.说到海鲜，我最喜欢虾。