The Dimetrodon was in fact a synapsid.

异齿龙实际上是一种动物。

The synapsids divided into four streams, only one of which survived beyond the Permian.

分成四支，只有一支闯过了二叠纪。

So there's branchiopods, ostracods, copepods, cladocerans...and besides the crustaceans, there's a lot more.

有叶足动物、介形动物、桡足类动物、水蚤类动物....除了甲壳类动物外，还有很多。这是真的，还有很多。

Synapsids were one of the four main divisions of early reptilian life, the others being anapsids, euryapsids, and diapsids.

是早期爬行动物的4个主要部之一，其他3个部分别是缺、调和双。

Synapsids had one hole in their lower temples; diapsids had two; euryapsids had a single hole higher up.

颥部有1个；双有2个；调只有上部1个。

The earliest armored fish we have fossils of is called Sacabambaspis, a member of the subclass known as Arandaspida.

我们有化石记录的最早的装甲鱼被称为萨卡班巴斯皮斯，它是阿拉达斯皮达的一员。

All modern amphibians—frogs, toads, salamanders, and the legless caecilians—belong to the same subclass of animals known as the Lissamphibia.

所有现代两栖动物——青蛙、蟾蜍、蝾螈以及无腿的盲蛇蛙——都属于同一个动物，称为滑体两栖。

Hematites, for example, was one of the earliest coleoids, and it had a cone-shaped shell inside its soft body.

例如， 红铁矿贝是最早的鞘动物之一，它柔软的身体内部有一个锥形的壳。

So with the ammonites gone, when conditions improved, the coleoids rose up and took their place.

所以当菊石消失后，当环境条件改善时，鞘动物兴起并取而代之。

And it's actually quite a small animal because contrary to all the famous theropods like the Tyrannosaurus, theropods started out as quite small animals.

与所有著名的兽脚目恐龙（如霸王龙）相反，事实上，它是一种体型娇小的动物，因为兽脚动物一开始是相当小的。

They were the first coleoids Like Sphooceras millions of years before them, coleoids wrapped their soft mantles around their hard shells.

他们是最早的鞘动物， 就像他们之前的千万年的Sphooceras一样，鞘动物将其柔软的外套膜包裹坚硬的壳周围。

But the coleoids were able to take refuge in the deep sea, and were no longer dependent on their shells.

但鞘动物能够躲进深海，并不再依赖它们的壳。

Armed with these adaptations, coleoids began to take advantage of a new niche: the deep sea.

凭借这些适应性特征，鞘开始利用一个新的生态位：深海。

Today, coleoids have colonized every marine ecosystem on the planet, and they play a vital role in ocean food webs.

今天， 鞘动物已经占据了地球上的每一个海洋生态系统，并海洋食物网中扮演着至关重要的角色。

Among the several subclasses (or " orders" in biology) of reptiles are snakes and lizards, turtles and tortoises, crocodiles and alligators, and the tuatara, a marine lizard in New Zealand.

几个(或生物学的“目”)的爬虫类中，有蛇和蜥蜴、乌龟和陆龟、鳄鱼和短吻鳄以及虫蜥蜴——一种现存于新西兰的海蜥蜴。

In Conseil I had a seasoned specialist in biological classification, an enthusiast who could run with acrobatic agility up and down the whole ladder of branches, groups, classes, subclasses, orders, families, genera, subgenera, species, and varieties.

康塞尔，我有一位经验丰富的生物分类专家，一位狂热的生物分类爱好者，他可以像杂技演员一样敏捷地分支、类群、、、目、科、属、属、种和变种的整个阶梯上上奔跑。