1.And conodonts were all of those things -- abundant, widespread, and composed of lots of distinctive species.

牙就是所有这些——数量丰富、分布广泛，并且由许多独特物组成。机翻

2.Likewise, in the Triassic Period, nearly every age is defined by the first appearance of various conodonts.

同样，在三叠纪时期，几乎每个时代都由各牙首次出现来定义。机翻

3.But conodont elements can do more than just that!

但牙元素可以做不止于此！机翻

4.In fact, many subdivisions of the Paleozoic are actually defined by when certain conodont species first or last appear.

事实上，古生代许多细分实际上是根据某些牙石物首次或最出现时间来定义。机翻

5.It turns out that conodont elements actually change color when they're heated up.

事实证明，牙元素在受热时实际上会改变颜色。机翻

6.But meanwhile, paleontologists still had no idea what kind of animals conodonts were.

但与此同时，古生物学家仍然不知道牙是么样动物。机翻

7.So conodont elements quickly became one of the handiest tools in the geologist toolkit.

因此，牙元素迅速成为地质学家工具包中最方便工具之。机翻

8.So it turned out that they weren't conodont animals; they were fossils of creatures that ate conodont animals!

所以事实证明它们不是牙石动物；它们是吃牙动物生物化石！机翻

9.Please allow me to introduce you to the conodonts.

请允许我向您介绍牙。机翻

10.But further study revealed that the conodont elements found in those fossils were actually in the animals' guts.

但进步研究表明，在这些化石中发现牙元素实际上存在于动物内脏中。机翻

11.In the 1970s, fossils of some vaguely fish-like creatures were found in Montana that were thought to be conodont animals.

在 20 世纪 70 年代，在蒙大拿州发现了些被认为是牙动物隐约鱼类生物化石。机翻

12.But while paleontologists were spending a hundred years or so debating what conodonts were, geologists were discovering what conodonts could do.

但是， 当古生物学家花了大约百年时间争论么是牙时，地质学家正在发现牙作用。机翻

13.So they were given the name conodont, which means " cone tooth." These elements are all verrry tiny.

因此，它们被命名为牙石，意思是“圆锥齿”。这些元素都非常小。机翻

14.Thanks to these beautiful specimens, we were able to learn that conodont animals were a kind of fish after all!

多亏了这些美丽标本，我们才知道牙动物毕竟是鱼！机翻

15.It was only marginally more fish-like than its earlier relatives, hagfish and conodonts, with which it shared a common ancestor.

它只比它早期亲戚盲鳗和牙更像鱼，它们与它们有个共同祖先。机翻

16.One hundred million years later, the warm, shallow seas were packed with tiny plants and animals — essentially, hors d'oeuvres for a plethora of bigger creatures like trilobites, conodonts, brachiopods, and corals.

千万年之，温暖浅海充满了微小植物和动物——基本上是大量大型生物开胃菜，如同三叶虫，牙虫，腕足类和珊瑚。

17.Check out " The Most Useful Fossils in  the World" , to learn more about conodonts.

查看“世界上最有用化石”，了解有关牙更多信息。机翻

18.And the fossils also revealed that the tiny, tooth-like conodont elements were concentrated in the animal's mouth -- but also in its throat!

化石还显示，细小、类似牙齿牙元素集中在动物嘴里——但也在它喉咙里！机翻

19.Like modern lampreys and hagfish, conodonts were jawless fish, and they were one of the earliest and most successful groups of vertebrates.

像现代七鳃鳗和盲鳗样， 牙是无颌鱼，它们是最早和最成功脊椎动物群之。机翻

20.Their final extinction brought an end to 300 million years of conodonts' role as a cornerstone of the world's ocean communities.

它们最终灭绝结束了 3 亿年来牙作为世界海洋群落基石作用。机翻