Which group of amniotes do you think dinosaurs belong to?

你认为恐龙属于哪一组羊膜动物？

These arid wastelands would’ve been uninhabitable for early tetrapods, but not for the amniotes.

这些干旱的荒地 对于早期的四足动物来说是不适宜居住的，但对于羊膜动物来说却不是。

So the initial 30% of the history of the amniote egg unfolded without leaving a trace.

因此，羊膜卵的最初 30% 的历史展开得无影无踪。

Amniotes with one temporal fenestrae are called synapsids.

具有一个颞孔的羊膜动物称为突触。

And amniotes with two temporal fenestrae are called diapsids.

具有两个颞孔的羊膜动物被称为双孔动物。

Because, eggs, especially soft-shelled, leathery eggs like we'd expect to see in early amniotes, don't fossilize well.

因为，蛋，尤其是我们期望在早期羊膜动物中看到的软壳革质蛋，不能很好地变成化石。

Amniotes can be subdivided into several groups based on the number of holes or fenestra in the skull.

羊膜动物可以根据头骨上的孔或孔的数量细分为几个组。

Now, reptiles are amniotes, and so are mammals.

现在，爬行动物是羊膜动物，哺乳动物也是。

But the amniotes, being better adapted to drier conditions, expanded into a variety of new niches, and dominated the land.

但是羊膜动物更好地适应了干燥的环境，扩展到各种新的生态位，并主宰了土地。

But on an increasingly dry planet, that gave amniotes a critical advantage.

但在一个日益干燥的星球上，这给了羊膜动物一个关键的优势。