One that's of special interest to us mammals: the cynodonts.

我们哺乳特别感兴的一种：犬齿兽类。

One way successful cynodonts, like Thrinaxodon, might have done this is through burrowing.

成功的犬齿兽类，如 Thrinaxodon，可通过挖洞来做到这一点。

Cynodonts probably also survived thanks to their ability to avoid predators and keep a low profile.

犬齿兽类也可幸下来，这要归功于它们开捕食者并保持低调。

Meanwhile, the descendants of those little cynodonts persisted through the entire Mesozoic Era, hiding in the dinosaur's shadows.

与此同时，那些小犬齿兽类的后代， 在整个中生代一直在，躲在恐龙的阴影下。

And in that burrow, researchers discovered the nearly complete remains of a small animal called Thrinaxodon, one of the early mammal relatives known as cynodonts.

在那个洞穴中， 研究人员发现了一种名为 Thrinaxodon 的小型几乎完整的遗骸，它是被称为犬齿兽的早期哺乳亲属之一。

The oldest known example of a cynodont burrow is dated to around 251 million years ago — just at the boundary between the Permian Period and the Triassic, when the Great Dying was coming to a close.

已知最古老的犬齿兽洞穴的例子可以追溯到大约 2.51 亿年前——就在二叠纪和三叠纪的交界处，当时大灭绝即将结束。