您现在的位置: 纽约时报中英文网 >> 纽约时报中英文版 >> 科学 >> 正文

中国科学家在琥珀中发现带羽毛的恐龙尾

更新时间:2016-12-15 10:54:32 来源:纽约时报中文网 作者:佚名

That Thing With Feathers Trapped in Amber? It Was a Dinosaur Tail
中国科学家在琥珀中发现带羽毛的恐龙尾

While most paleontologists dig up prehistoric bones from the ground, Lida Xing hunts for fossils in the amber markets of Myanmar. In 2015, he made a remarkable find: Trapped in what looked like golden glass was the feathered tail of a dinosaur.

大多数古生物学家都是从地下挖掘史前遗骨,邢立达却在缅甸的琥珀市场上寻找着化石的踪迹。2015年,他有了一个了不起的发现:在看似像一块金色玻璃的东西里封存着一段有羽毛的恐龙尾部。

Along with the primitive plumage, the 99-million-year-old amber also preserved soft tissue and eight complete vertebrae. The tail bones indicated that the specimen belonged to a dinosaur that was not a prehistoric bird and also provided researchers with insight into the evolution of feathers.

除了原始羽毛,这块9900万年前的琥珀还将软组织和8节完整的椎骨保存了下来。尾骨显示该标本来自一只恐龙,而非史前鸟类,还让研究者得以更加深入地了解羽毛的演化。

A 99-million-year-old piece of amber with a feathered dinosaur tail trapped inside.
来自9900万年前的一块琥珀内,封存着一条长着羽毛的恐龙尾巴。

“This is the first time that skeletal material from a dinosaur has been found in amber,” Dr. Xing, who is a paleontologist at China University of Geosciences in Beijing, said in an email. He and his colleagues published their findings Thursday in the journal Current Biology.

“这是首次在琥珀中发现恐龙的骨骼物质,”北京中国地质大学的古生物学家邢立达在电子邮件中表示。周二,他和同事在《当代生物学》(Current Biology)期刊上发表了他们的研究成果。

After performing a CT scan and microscopic analysis, Dr. Xing and his colleagues realized that the feathers did not belong to a bird because the specimen’s tail vertebrae were not fused into a rod, as they are in modern birds. The feathers most likely belonged to a baby nonavian theropod, meaning it looked more similar to a velociraptor or Tyrannosaurus rex than to a modern bird. That said, it was probably only about the size of a sparrow.

经过CT扫描和显微分析,邢立达及其同事意识到这些羽毛并不属于一只鸟,因为该标本的尾椎没像现代鸟类那样结合成杆状。这些羽毛极有可能属于一只年幼的非鸟兽脚类恐龙,意即样子更接近伶盗龙或者暴龙,而非现代鸟类。据推测,它的大小或许跟一只麻雀相仿。

After death, the tiny dinosaur’s body was most likely covered in tree resin. The resin is produced as a defense mechanism against insect infestations. When it dries it becomes a plasticlike substance that can survive for millions of years.

这只小恐龙死后,尸体极有可能被裹在树脂里。树脂是树木为防御昆虫侵袭而分泌的物质,变干后呈塑料状,可以留存成百上千万年。

“Once the resin leaks out on the side of the tree it’s like a big sticky trap waiting for anything to fall into it,” said Ryan McKellar, a paleontologist at the Royal Saskatchewan Museum in Canada and an author of the study. “Then once the next resin falls on top of the existing one, it seals it in.”

“树脂从树干侧面流出后,就好像一个富于粘性的大陷阱,等待着自投罗网的任何东西,”该论文作者之一、加拿大萨斯喀彻温省皇家博物馆(Royal Saskatchewan Museum)的古生物学家瑞安·麦凯勒(Ryan McKellar)说。“等到新流出的树脂落到原有树脂顶上,它就会被封存起来。”

After Dr. Xing found the amber, he sent it to Dr. McKellar, an amber expert, to further investigate the specimen.

邢立达发现了这块琥珀以后,将其送到了身为琥珀专家的麦凯勒手中,以便对标本做进一步研究。

“When it hit my desk, I was blown away,” Dr. McKellar said. “It’s one of those things where you’re like ‘Wow, it’s the closest you’ll ever get to holding a fleshed-out dinosaur in your hands.”

“当它来到我的案头时,我深受震撼,”麦凯勒说。“这种东西会让你觉得,‘哇,把一只活生生的恐龙握在手中,差不多就是这种感觉了吧。’”

Using a high-powered microscope, Dr. McKellar recorded images of the amber. He found that the underside of the feathers was white and the top was chestnut brown. But it was not the color that fascinated him the most.

麦凯勒使用高倍显微镜记录下了琥珀的图像。他发现羽毛腹面呈白色,背面则呈栗棕色。但最让他感兴趣的并不是色彩。

“I was seriously puzzled by the feather structure we’re seeing in this sample,” he said.

“我们在这个标本中看到的羽毛结构曾经让我极为困惑,”他说。

Most modern bird feathers have a central shaft called a rachis; think of the ink rod in a quill pen. Branching from the rachis are smaller shafts called barbs, and then branching from the barbs are even smaller filaments called barbules. But this specimen lacked the rachis; it just had barbs and barbules down its ribbonlike tail.

大多数现代鸟类的羽毛都有被称为羽轴的中心轴;想想鹅毛笔的墨水杆吧。沿着羽轴伸展开去的较小的杆状物叫做羽枝,沿着羽枝伸展开去的更小的细丝则叫小羽枝。但这件标本没有羽轴,带状尾巴上只有羽枝和小羽枝。

“They are more fuzzy than sleek,” Dr. McKellar said. “It shapes our view of how feathers came to develop in modern birds, and it gives us a rare glimpse of what dinosaurs looked like and potentially what feathers were being used for in the mid-Cretaceous.”

“它们毛茸茸的,没那么光滑,”麦凯勒博士说。“这就帮助我们形成了对现代鸟类羽毛的演化的认识,并为我们提供了一个窥探恐龙面貌的难得机会,还有可能帮助我们探寻白垩纪中期的羽毛是什么样子。”

The finding suggests that the barbs and barbules evolved before the rachis in feathers. That is interesting because the rachis seems to aid in flight. It could be that dinosaurs with more primitive feathers used them for temperature regulation, camouflage and visual signaling, rather than flight.

该发现表明,羽毛中的羽枝和小羽枝是先于羽轴进化出来的。这就很有趣了,因为羽轴似乎有助于飞行。拥有更为原始的羽毛的恐龙,当初可能将其用于调节身体温度、伪装和发出视觉信号,而非辅助飞行。

“It’s a spectacular specimen,” said Mark Norell, a paleontologist from the American Museum of Natural History, who was not involved in the study. He added that because the feathers were found with the vertebrae, there was no question they belonged to a nonavian theropod dinosaur as opposed to a prehistoric bird. “This is a novel feather type that we haven’t seen before.”

“这是一件令人惊叹的标本,”美国自然历史博物馆(American Museum of Natural History)的古生物学家马克·诺雷尔(Mark Norell)说。并未参与该研究的诺雷尔还表示,鉴于羽毛是和那些椎骨一起被发现的,毫无疑问它们属于一只非鸟兽脚类恐龙,而非史前鸟类。“这是我们以前没有见过的一种新的羽毛类型。”

“全文请访问纽约时报中文网,本文发表于纽约时报中文网(http://cn.nytimes.com),版权归纽约时报公司所有。任何单位及个人未经许可,不得擅自转载或翻译。订阅纽约时报中文网新闻电邮:http://nytcn.me/subscription/”

相关文章列表