This is because they are spawned from polyps on the seabed.

这是因它们是从海底的螅体中产生的。

He's also a polyp, bristling and squishy, a creature Picasso himself called a turd.

他本人则像只竖着刚毛粘乎乎的螅，对这生物，毕加索之一坨屎。

But hydra have neural nets of diffuse brain cells, rather than a dense organ-like we have.

但螅有弥漫的脑细胞构成的神经网络，而不像我们有一密集的器官。

See, hydra bodies are really simple: one head and one foot lined up along a single body axis.

看，螅的身体真的很简单：一头和一只脚沿着一身体轴排成一行。

Coral is made of tiny transparent animals called polyps, with thousands of them in each chunk.

珊瑚由螅体的微小明动物组成，中有数千。

Hydra have thin, parallel actomyosin fibers running throughout their body, like our muscle tissue.

螅有细而平行的肌动球蛋白纤维遍布全身，就像我们的肌肉组织一样。

No decline in fertility, or increase in mortality, was observed at any point in the hydra life cycle.

在螅生命周期的任何时候都没有观察到生育率下降或死亡率增加。

And even though hydra regeneration is a little more extreme, it’s similar to how we humans heal wounds and develop as embryos.

尽管螅的再生有点极端，但它类似于我们人类治愈伤口和发育成胚胎的方式。

Every cell in a hydra’s body is replaced every three to four weeks, by fresh cells produced by brand new stem cells.

螅体内的细胞三到四星期就会被全新干细胞产生的新鲜细胞更换一次。

But unlike butterflies, if Turritopsis get wounded or if times get tough, they can morph backwards, reverting to their immature polyp form until conditions improve.

而与蝴蝶不同的是，如果受伤或者生存条件恶劣，灯塔母们可以回到之前的阶段，在状况改善之前变回它们非成熟期时类似螅虫的样子。

Like some giant tortoises that can reach near 200 years and some small freshwater animals of the genus Hydra that appear not to age at all.

像一些巨型龟的寿命能活到将近两百岁，还有一些螅属的淡小动物，它们看起来一点也没有走向衰老的痕迹。

On the other hand, slices of hydra shaped like closed rings didn’t fold so well, and formed spheroids with different regions of actomyosin aligned in different ways.

另一方面，形状像闭合环的螅切片折叠得不太好， 形成了不同区域的肌动球蛋白以不同方式排列的球体。

In addition to their characteristics, in these cnidarians, there's the leap of the formation of a third layer of tissue during development, from the polyp state to certain jellyfish, such as some that belong to the taxon of hydromedusae.

除了它们的特征，在这些刺胞动物之间，在发育过程中，还有第三层组织形成的飞跃，从息肉状态到某些母，比如一些属于螅纲的母。

This hydra is a freshwater polyp that’s a centimeter long, and reproduces both asexually and sexually, can regenerate after it’s been cut into pieces, including being able to regenerate its ENTIRE HEAD, and, as it turns out, is pretty much immortal.

这种螅是一种一厘米长的淡螅体，可以无性繁殖和有性繁殖， 在被切成碎片后可以再生，包括能够再生它的整头部， 而且事实证明， 它几乎是不朽的。