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[翻译]SCIENCE IN THE NEWS - The Longest Living Vertebrate is… a Shark

更新时间:2016/8/28 8:49:41 来源:本站原创 作者:佚名

New research found the longest living animal on Earth with a backbone is – a shark.

新的研究发现,地球上最长寿的脊椎动物是一种鲨鱼。

The research, published in Science magazine, found the Greenland shark is the longest living vertebrate – or animal with a backbone-- in the world. The gray-colored sharks live in the cold waters of the Arctic and are named after Greenland, the world’s largest island.

这项发表在《科学》杂志上的研究发现,格陵兰鲨是世界上最长寿的脊椎动物。这种灰色的鲨鱼生活在北极地区的冰冷水域,并且以全球最大的岛屿格陵兰岛命名。

After examining one of these sharks, scientists decided it was born in the icy waters about 400 years ago, and only died recently.

科学家在检查其中一头鲨鱼后判断它大约于400年前在这片冰冷水域中出生,并且最近才死亡。

An international team of biologists and physicists was able to estimate the ages of 28 dead female Greenland sharks by studying the lenses of their eyes. It is a new way to learn the age of an animal.

一个由生物学家和物理学家组成的国际小组通过研究这28头死去的雌性格林兰鲨的眼球晶体能够估算出它们的年龄。这是一种了解动物年龄的新方法。

Eight of the sharks were probably 200 years old or more, and could even have been 300 years old. That would make them older than the bowhead whale, which earlier was believed to have been the oldest vertebrate at about 211 years old, according to the Associated Press.

据美联社报道,其中8头鲨鱼可能有200岁或以上,甚至可能已经300岁了。这使得它们的寿命超过了弓头鲸,之前一直认为寿命在211岁左右的弓头鲸是最长寿的脊椎动物。

This also means Greenland sharks can live more than three times longer than humans. Many people these days can expect to live into their eighties. African elephants average about 70 years.

这也意味着格林兰鲨的寿命是人类的三倍以上。如今很多人有望活到80多岁。非洲象的平均寿命大约为70年。

The oldest of the Greenland sharks the scientists studied was nearly 5 meters long. It was thought to have been 392 years old when it was caught four years ago. But because the testing method is so new, it is not exact.

科学家们研究的最长寿的格林兰鲨将近5米长,据认为四年前这头鲨鱼被捕捞时已经有392岁。但是因为这种测试方法是新出现的,所以尚不准确。

The study’s lead author is Julius Nielsen, a marine biologist from Denmark. He says the 392 number could be off by as much as 120 years in either direction. That means the shark was probably born sometime between the years 1500 and 1740, with 1620 being the most likely.

这项研究的主要作者是丹麦海洋生物学家朱利叶斯·尼尔森(Julius Nielsen)。他说,392这个数字上下有高达120年的出入,这意味着这头鲨鱼可能出生在1500年到1740年之间,而1620年最为接近。

"It's an estimate. It's not a determination," Nielsen said. "It is the best we can do."

尼尔森说,“这只是估算值,并非测定值。我们最多只能做到这点。”

Even at the lowest age, the shark would have been 272 years old when it died, and still would be the longest-living animal with a backbone, Nielsen said.

尼尔森表示,即使是估算的最小年龄,这头鲨鱼在死亡时也已经272岁了,它仍然是最长寿的脊椎动物。

"I don't know why they get as old, but I hope someone will find out," Nielsen said.

尼尔森说,“我不知道它们为什么这么长寿,但是我希望有人会找出来。

Christopher Lowe is director of the shark lab at California State University in Long Beach. He was not part of the study, but praised it.

克里斯托弗·洛(Christopher Lowe)是加州大学长滩分校鲨鱼实验室的主任。他并未参与该研究,但是对此赞不绝口。

In an email to AP, Lowe wrote that he is not surprised that Greenland sharks live a long time. But, he said, "I'm really shocked by the magnitude of that longevity."

洛在一封写给美联社的邮件中写道,他对格陵兰鲨的长寿并不感到意外。但他表示,“我对这一长寿的量级真的感到震惊。”

Lowe said that when the water is deep and cold, that usually means fish can live a long time.

洛表示,深冷水域通常意味着鱼类可以活很长时间。

Why? It could be because the cold water slows down an animal’s metabolism—or the way it processes food into energy.

为什么呢?这可能是因为冷水会减慢动物的新陈代谢,也就是将食物转化为能量的方式。

While Greenland sharks are among the largest fish in the world, they only grow about one centimeter a year. That fact caught Nielson’s attention and he decided to find a way to determine their age.

虽然格林兰鲨是全球最大的鱼类之一,它们每年只生长1厘米左右。这一情况引起了尼尔森的注意,他决定找到一种办法来确定它们的年龄。

To get the age estimates, Nielsen and his team used a complex system that combines chemical tests, mathematical models and growth measurements.

为了估算年龄,尼尔森及其小组采用了一种结合化学试验、数学模型和生长测量的复杂系统。

The research also suggested the female Greenland sharks do not mate and have babies until they are about 150 years old.

该研究还表明,雌性格林兰鲨在大约150岁前不会交配以及产仔。

That may not be good news, because the Greenland sharks may not have many young. If too many are caught, the species could die out.

这也许不是一个好消息,因为这样格陵兰鲨就不会有很多幼仔。如果太多格陵兰鲨被捕捞,这种物种就可能会灭绝。

The scientists worry that the sharks are being caught up and killed with other species by commercial fisheries.

科学家们担心这种鲨鱼同其它物种一起被商业渔业捕捞和杀害。

Some animals without backbones can live even longer. A clam, found in waters off Iceland, lived to be 507 years old. And scientists say some sponges are estimated to be more than 2,000 years old.

一些无脊椎动物可以活得更久。冰岛水域发现的一种蛤可以活到507岁。科学家称,一些海绵动物估计超过了2千岁。

I’m Anne Ball, and I'm Bryan Lynn.

Words in This Story

vertebrate – n. animal with a backbone

lens – n. the clear part of the eye that focuses light to see images

determination – n. finding out or calculating something

magnitude – n. the size or importance of something

longevity – n. the length of life

metabolism – n. the process that a living thing makes food and water into energy

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