美国科学60秒 SSS 2013-03-14
时间:2018-12-24 作者:英语课 分类:Scientific American(三)月
英语课
This is Scientific American 60 second Science, I’m Sophie Bushwick. Got a minute?
It was thought that saltwater seas separated Central and South America millions of years ago. But a recent discovery may render that idea all wet. Because archaeologists in Panama have dug up the remains 1 of ancient alligator 2 relatives—which were freshwater creatures. The work is in the Journal of Vertebrate Paleontology.
Excavations 3 at the Panama Canal have turned up many fossils. Recently, two partial skulls 4 were found embedded 5 in rocks that date back more than 19 million years, which makes them the oldest crocodilian fossils ever found in Central America. The skulls are from two species of the freshwater reptiles 6 called caimans. Modern caimans are related to North American alligators 7 but live only in South America.
To reach Panama, the caimans must have left South America around the beginning of the Miocene epoch 8, when ocean separated the two continents. These freshwater animals should only have been able to cross a short expanse of saltwater. So at the time, Central and South America may have been much closer than we thought. Either that, or those caimans hitched 9 a ride
Thanks for the minute for Scientific American 60 second science, I’m Sophie Bushwick.
1 remains
n.剩余物,残留物;遗体,遗迹
- He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
- The remains of the meal were fed to the dog.残羹剩饭喂狗了。
2 alligator
n.短吻鳄(一种鳄鱼)
- She wandered off to play with her toy alligator.她开始玩鳄鱼玩具。
- Alligator skin is five times more costlier than leather.鳄鱼皮比通常的皮革要贵5倍。
3 excavations
n.挖掘( excavation的名词复数 );开凿;开凿的洞穴(或山路等);(发掘出来的)古迹
- The excavations are open to the public. 发掘现场对公众开放。
- This year's excavations may reveal ancient artifacts. 今年的挖掘可能会发现史前古器物。 来自辞典例句
4 skulls
颅骨( skull的名词复数 ); 脑袋; 脑子; 脑瓜
- One of the women's skulls found exceeds in capacity that of the average man of today. 现已发现的女性颅骨中,其中有一个的脑容量超过了今天的普通男子。
- We could make a whole plain white with skulls in the moonlight! 我们便能令月光下的平原变白,遍布白色的骷髅!
5 embedded
a.扎牢的
- an operation to remove glass that was embedded in his leg 取出扎入他腿部玻璃的手术
- He has embedded his name in the minds of millions of people. 他的名字铭刻在数百万人民心中。
6 reptiles
n.爬行动物,爬虫( reptile的名词复数 )
- Snakes and crocodiles are both reptiles. 蛇和鳄鱼都是爬行动物。 来自《简明英汉词典》
- Birds, reptiles and insects come from eggs. 鸟类、爬虫及昆虫是卵生的。 来自《现代汉英综合大词典》
7 alligators
n.短吻鳄( alligator的名词复数 )
- Two alligators rest their snouts on the water's surface. 两只鳄鱼的大嘴栖息在水面上。 来自辞典例句
- In the movement of logs by water the lumber industry was greatly helped by alligators. 木材工业过去在水上运输木料时所十分倚重的就是鳄鱼。 来自辞典例句