2022年12月25日 VOA慢速英语：内华达化石遗址可能是古代爬行动物的诞生地

 

Scientists have found new information about an area in the American state of Nevada that contains fossils of giant marine reptiles.
科学家们发现了有关美国内华达州一个地区的新信息，该地区包含巨型海洋爬行动物的化石。
 
Scientists previously thought it was a place where they came to die. But they now think it may have been where the reptiles came to give birth.
此前，科学家们认为这是他们死亡的地方。但他们现在认为它可能是爬行动物产子的地方。
 
The area is famous for its fossils from giant ichthyosaurs. Those are reptiles that controlled the ancient seas and could grow up to the size of a school bus.
该地区以巨型鱼龙化石而闻名。这些是控制古代海洋的爬行动物，可以长到校车那么大。
 
The name ichthyosaur means fish lizard. The creatures were underwater predators with large flippers and big mouths full of teeth.
鱼龙这个名字的意思是鱼蜥蜴。这些生物是水下捕食者，有大鳍状肢和长满牙齿的大嘴巴。
 
The ichthyosaur bones in Nevada were found in the 1950s. Since then, many scientists who study fossils, or paleontologists, have investigated how all these creatures could have died together. Now, researchers have proposed a different idea in a study recently published in the publication Current Biology.
内华达州的鱼龙骨骼是在 1950 年代发现的。从那时起，许多研究化石的科学家或古生物学家研究了所有这些生物如何一起死亡。现在，研究人员在最近发表在《当代生物学》杂志上的一项研究中提出了不同的想法。
 
"Several lines of evidence all kind of point towards one argument here: That this was a place where giant ichthyosaurs came to give birth," said co-writer Nicholas Pyenson. He is a fossil marine mammals expert at the Smithsonian National Museum of Natural History.
“几条证据都指向这里的一个论点：这是巨型鱼龙出生的地方，”合著者尼古拉斯·佩恩森说。他是史密森尼国家自然历史博物馆的海洋哺乳动物化石专家。
 
The area is in Nevada's Berlin-Ichthyosaur State Park. The area used to be a sea. But it now sits in a dry area near an old mining town, said lead writer Randy Irmis, a paleontologist at the University of Utah.
该地区位于内华达州的柏林鱼龙州立公园。该地区曾经是大海。但它现在坐落在一个古老的 采矿城镇附近的干旱地区，主要作者、犹他大学的古生物学家 Randy Irmis 说。
 
The creature's skeletons are very large. Their vertebrae are about 25 centimeters. Bones from their flippers are as thick as large rocks. To get a look at the skeletons, researchers used 3D scanning to create a detailed digital model, Irmis said.
这种生物的骨骼非常大。它们的椎骨长约 25 厘米。他们脚蹼上的骨头和大石头一样厚。Irmis 说，为了查看骨骼，研究人员使用3D扫描创建了一个详细的数字模型。
 
They identified fossils from at least 37 ichthyosaurs from the area, dating back about 230 million years. The bones were preserved in different rock layers. That suggests the creatures could have died hundreds of thousands of years apart rather than all at once, Pyenson said.
他们鉴定了该地区至少 37 种鱼龙的化石，可追溯到大约 2.3 亿年前。骨头保存在不同的岩层中。Pyenson 说，这表明这些生物可能相隔数十万年而不是同时死亡。
 
A major discovery came when the researchers found some tiny bones among the massive adult fossils. The researchers learned that they belonged to embryos and newborns, Pyenson said.
当研究人员在巨大的成年化石中发现一些微小的骨头时，一项重大发现就来了。Pyenson 说，研究人员了解到它们属于胚胎和新生儿。
 
The researchers concluded that the creatures traveled to the area in groups for protection as they gave birth, like today's marine animals. The fossils are believed to be from the mothers and their young ones that died there over the years.
研究人员得出结论，这些生物在分娩时成群结队地前往该地区寻求保护，就像今天的海洋动物一样。这些化石被认为来自多年来死在那里的母亲和她们的孩子。
 
"Finding a place to give birth separated from a place where you might feed is really common in the modern world — among whales, among sharks," Pyenson said.
Pyenson 说：“在现代世界，鲸鱼和鲨鱼中，找到一个与喂食的地方分开的地方分娩是很常见的，”Pyenson 说。
 
Other information helped rule out some previous explanations.
其他信息有助于排除之前的一些解释。
 
Testing the chemicals in the dirt did not turn up any signs of volcanic activities or major changes to the local environment. And research showed that the reptiles were preserved on the ocean floor far from the shore — meaning they probably did not die in a mass beaching event, Irmis said.
测试泥土中的化学物质没有发现任何火山活动或当地环境发生重大变化的迹象。Irmis 说，研究表明，这些爬行动物保存在远离海岸的海底——这意味着它们可能没有在大规模搁浅事件中死亡。
 
The new study offers a likely explanation for an area that has confused paleontologists for many years, said Dean Lomax. He is an ichthyosaur specialist at England's University of Manchester who was not involved with the research.
迪恩·洛马克斯 (Dean Lomax) 说，这项新研究为多年来困扰古生物学家的一个区域提供了一个可能的解释。他是英国曼彻斯特大学的鱼龙专家，并未参与这项研究。
 
All may not be known, but the study "really helps to unlock a little bit more about this fascinating site," Lomax said.
一切可能不为人知，但这项研究“确实有助于更多地了解这个迷人的网站，”洛马克斯说。