Nowadays, evolution just tinkers with old body plans.

如今，进化只是按照老的体形横剖面修修补补。

The crazy thing is that scorpions' basic body plan really hasn't changed.

疯狂的是，蝎子的基本身型并没有改变。

Studies of a rather unfortunate-looking worm suggest that we're the new kids on the body plan block.

对一只看起来很不幸的蠕虫的研究表明，我们才是身体结构方面上的新孩子。

And it turns out this is a pretty solid body plan, because scorpions just keep existing.

事实证明这是一个相当可靠的身型，因为蝎子持续存在着。

All shared a basic body plan of three parts, or lobes-head, tail, thorax-from which comes the name.

三叶虫的身体都有个相同的基本结构，分为三个部分或三片叶——头、尾和胸。三叶虫的名字由此而来。

Which is perfect because we animals are born with essentially the same body plan that we'll carry into adulthood.

这很完美，因为我们动物天生的身体结构与成年后的身体结构基本相同。

Many of the creatures employed body plans that were not simply unlike anything seen before or since, but were bizarrely different.

许多生物的横剖面是以前和之后完全没有见过的，简直是奇形怪状的。

So you can take on all these different body plans.

所以你可以接受所有这些不同的身体计划。

That's because they have simple body plans – essentially tube-like structures that filter feed – and they have relatively few types of cell.

这是因为它们的身体结构简单，本质上是过滤饲料的管状结构，并且它们的细胞种类相对较少。

Bilaterean body plans can be roughly divided into three sections.

两侧身体的轮廓可以大致分为三个部分。

By this time, dinosaurs had already acquired a variety of body plans and adaptations.

到这个时候，恐龙已经获得 了各种身体计划和适应。

They have a relatively simple body plan, and relatively few different types of cells, which probably helps.

它们的身体结构相对简单，不同类型的细胞相对较少， 这可能有所帮助。

Generally in the animal kingdom, once you evolve a bilaterally symmetrical body plan you don’t go back.

一般来说，在动物王国中，一旦你进化出双边对称的身体计划，你就不会再回头了。

Well, it looks like the roots of that weird slinky body plan lie in the expansion of grasslands.

好吧，看起来那个奇怪的紧身计划的根源在于草原的扩张。

And this led to the formation of new body plans that the world had never seen before.

这导致 了世界从未见过的新身体计划的形成。

Their weird body plans were just a kind of youthful exuberance - the evolutionary equivalent, as it were, of spiked hair and tongue studs.

它们古怪的体形横剖面只是处于一种生气勃勃的青春阶段——在某种程度上类似于进化中的尖毛和舌尖。

And once they developed their multi-armed, face-down body plan, starfish had a foot in the door.

一旦他们开发出多臂、面朝下的身体计划，海星就踏入了大门。

And this is where we see those two major mustelid body plans start to take shape.

这就是我们看到这两个主要的鼬类身体计划开始形成的地方。

Well, scientists may now have an answer, and they’ve found it by looking at the genes which encode body plans.

好吧，科学家现在可能有了答案，他们通过观察编码身体计划的基因找到了答案。

But how does a body plan get skinnier?

但是身体计划如何变得更苗条呢？