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，并且由许多独特的种组成。

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

因此，牙素迅速成为地质学家工具包中最方便的工具之一。

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

事实上，古生代的许多细分实际上是根据某些牙石种首次或最后出现的时间来定义的。

But conodont elements can do more than just that!

但牙素可以做的止于此！

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

它只比它的早期亲戚盲鳗和牙更像鱼，它们与它们有一个共同的祖先。

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种牙的首次出现来定义。

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

事实证明，牙素在受热时实际上会改变颜色。

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

但与此同时，古生学家仍然知道牙是一种什么样的。

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

所以事实证明它们是牙石；它们是吃牙的生的化石！

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

但是， 当古生学家花了大约一百年的时间争论什么是牙时，地质学家正在发现牙的作用。

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

但进一步的研究表明，在这些化石中发现的牙素实际上存在于的内脏中。

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，在蒙大拿州发现了一些被认为是牙的隐约鱼类生的化石。

Please allow me to introduce you to the conodonts.

请允许我向您介绍牙。

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

多亏了这些美丽的标本，我们才知道牙毕竟是一种鱼！

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”。这些素都非常小。

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

像现代的七鳃鳗和盲鳗一样， 牙是无颌鱼，它们是最早和最成功的脊椎群之一。

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

它们的最终灭绝结束了 3 亿年来牙作为世界海洋群落基石的作用。

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.

一千万年之后，温暖的浅海充满了微小的植和——基本上是大量大型生的开胃菜，如同三叶虫，牙虫，腕足类和珊瑚。

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，细小的、类似牙齿的牙素集中在的嘴里——但也在它的喉咙里！

Throughout their history, conodonts were affected by several mass extinctions, including the Great Dying at the end of the Permian Period 252 million years ago.

纵观它们的历史， 牙受到了几次大规模灭绝的影响，包括 2.52 亿年前二叠纪末期的大灭绝。