纪录片《侏罗纪之谜》 第23期 大西洋的形成（在线收听）

And scientists realised there was a barrier that was beginning to form at exactly the right time,

科学家们意识到那道屏障正好也在当时开始形成

something else that was created as the super-continent split apart: the Atlantic Ocean.

超大陆的分裂还创造了别的东西：大西洋

In the mid-Jurassic the new ocean flooded in,

中侏罗世诞生了一片新的大洋

cutting present day North America off from South America.

隔开了今天的北美洲和南美洲

Because of the oceans, animals would have been isolated on the newly formed continents

因为有了海洋，动物被隔离在新生大陆上

allowing them to evolve separately and creating many new types of dinosaur.

使得它们独自进化成许多种新的恐龙

It's a process scientists call vicariance, but vicariance is very difficult to prove.

科学家们称这一过程为地理分隔，但是地理分隔很难得到证明

Up until now it's been very difficult to demonstrate the connection between vicariance and dinosaur diversity in the middle Jurassic.

直到现在我们都很难证明地理分隔和中侏罗世恐龙多样性之间的联系

We have lacked any site that has sufficient high resolution to show us any connection between these processes.

我们还没能找到一个地方能充分说明这些过程之间的关系

But that was before Argentina.

但这只是在阿根廷这次发现之前

The first clues about vicariance came from something surprising,

第一条地理分隔的线索来自一个令人吃惊的发现

a discovery that seemed to have nothing to do with dinosaurs.

这一发现似乎与恐龙没有任何关系。