2022年12月25日 VOA慢速英語：內華達化石遺址可能是古代爬行動物的誕生地

 

Scientists have found new information about an area in the American state of Nevada that contains fossils of giant marine reptiles.
科學家們發(fā)現了有關美國內華達州一個地區(qū)的新信息，該地區(qū)包含巨型海洋爬行動物的化石。
 
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，科學家們認為這是他們死亡的地方。但他們現在認為它可能是爬行動物產子的地方。
 
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.
該地區(qū)以巨型魚龍化石而聞名。這些是控制古代海洋的爬行動物，可以長到校車那么大。
 
The name ichthyosaur means fish lizard. The creatures were underwater predators with large flippers and big mouths full of teeth.
魚龍這個名字的意思是魚蜥蜴。這些生物是水下捕食者，有大鰭狀肢和長滿牙齒的大嘴巴。
 
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.
內華達州的魚龍骨骼是在 1950 年代發(fā)現的。從那時起，許多研究化石的科學家或古生物學家研究了所有這些生物如何一起死亡?，F在，研究人員在最近發(fā)表在《當代生物學》雜志上的一項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.
“幾條證據都指向這里的一個論點：這是巨型魚龍出生的地方，”合著者尼古拉斯·佩恩森說。他是史密森尼國家自然歷史博物館的海洋哺乳動物化石專家。
 
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.
該地區(qū)位于內華達州的柏林魚龍州立公園。該地區(qū)曾經是大海。但它現在坐落在一個古老的 采礦城鎮(zhèn)附近的干旱地區(qū)，主要作者、猶他大學的古生物學家 Randy Irmis 說。
 
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.
這種生物的骨骼非常大。它們的椎骨長約 25 厘米。他們腳蹼上的骨頭和大石頭一樣厚。Irmis 說，為了查看骨骼，研究人員使用3D掃描創(chuàng)建了一個詳細的數字模型。
 
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.
他們鑒定了該地區(qū)至少 37 種魚龍的化石，可追溯到大約 2.3 億年前。骨頭保存在不同的巖層中。Pyenson 說，這表明這些生物可能相隔數十萬年而不是同時死亡。
 
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.
當研究人員在巨大的成年化石中發(fā)現一些微小的骨頭時，一項重大發(fā)現就來了。Pyenson 說，研究人員了解到它們屬于胚胎和新生兒。
 
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.
研究人員得出結論，這些生物在分娩時成群結隊地前往該地區(qū)尋求保護，就像今天的海洋動物一樣。這些化石被認為來自多年來死在那里的母親和她們的孩子。
 
"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 說：“在現代世界，鯨魚和鯊魚中，找到一個與喂食的地方分開的地方分娩是很常見的，”Pyenson 說。
 
Other information helped rule out some previous explanations.
其他信息有助于排除之前的一些解釋。
 
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.
測試泥土中的化學物質沒有發(fā)現任何火山活動或當地環(huán)境發(fā)生重大變化的跡象。Irmis 說，研究表明，這些爬行動物保存在遠離海岸的海底——這意味著它們可能沒有在大規(guī)模擱淺事件中死亡。
 
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·洛馬克斯 (Dean Lomax) 說，這項新研究為多年來困擾古生物學家的一個區(qū)域提供了一個可能的解釋。他是英國曼徹斯特大學的魚龍專家，并未參與這項研究。
 
All may not be known, but the study "really helps to unlock a little bit more about this fascinating site," Lomax said.
一切可能不為人知，但這項研究“確實有助于更多地了解這個迷人的網站，”洛馬克斯說。