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

但水螅有弥漫的脑细胞构成的网络，而不像我们有一个密集的器官。

No matter what happens, though, Alexander's three-headed hydra problem just became a two-headed one.

不管发生什么，亚历山大的三头怪问题现在变成了头了。

Instead of a brain, hydras have nerve nets, the most basic nervous systems in nature.

水螅没有大脑，而是拥有网络 ，这是自然界中最基本的系统。

This year, a group of Japanese scientists demonstrated that hydras sleep.

今年，一群日本科学家 证明了水螅睡觉。

Can humans learn the secrets of longevity from the hydra, a tiny aquatic creature capable of indefinite self-renewal?

人类能否从水螅这种具有无限自我更新能力的微小水生生物身学到长寿的秘诀呢？

When you see a Source hydra panel, it looks a little bit like a normal solar module, except for just a little thicker.

Source 水力板看起来有点像普通的太阳能模块，只是稍微厚了一点。

So these regenerated hydra were more deformed, and usually had multiple body axes – like two mouths and two feet.

所以这些再生的水螅形态更加畸形，通常具有多个身体轴——比如个个脚。

Like the mythical hydra, maybe this is a beast that never can be truly  slain with just chopping off its heads.

就像话中的九头蛇一样，也许这是一种永远无法通过砍下头来真正杀死的野兽。

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

看看，水螅的身体非常简单：一个头部一个足部沿着单一身体轴线排列。

The alignment of actomyosin fibers in the spheroid lays out a structure that gets inherited throughout the new hydra’s body.

球状体中肌动蛋白-肌球蛋白纤维的排列构成了一种结构，这种结构会被继承到新生水螅的身体中。

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

尽管水螅的再生能力有点极端，但它类似于我们人类如何愈合伤口胚胎如何发育的过程。

But there are a few exceptions to this get-older-and-die thing -- including, it turns out, tiny sea creatures called hydras.

但是， 这种变老死亡的事情也有一些例外——事实证明，包括被称为九头蛇的微小海洋生物。

The team followed more than two thousand individual hydras for a combination of 3.9 million days.

研究团队跟踪了超过千只个体水螅，总计长达390万天。

And hydra – the squishy tube-shaped freshwater animal, not the mythological sea serpent or Marvel villain – are really, really good at it.

而且水螅——那种柔软的管状淡水生物，不是话中的海蛇或漫威反派——非常非常擅长此道。

And THAT is what I have been able to do that most hydras can’t.

而那就是我能做到而大多数水螅做不到的事情。

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

在水螅的生命周期中，任何阶段都没有观察到生育力下降或死亡率升。

So how do hydras not decline with age?

那么水螅为什么不会随着年龄增长而衰退呢？

But the most important factor is most likely that hydras constantly produce new stem cells.

但最重要的因素可能是水螅不断产生新的干细胞。

The hydras they studied were between zero and 41 years old, and they observed them over a period of 8 years.

他们研究的水螅年龄在零到41岁之间，观察期长达8年。

As far back as 1968, researchers found that hydra use neurotransmitters like glutamate to activate neurons and orchestrate eating, which sounds like something an organism with a brain would do.

早在1968年，研究人员就发现水螅会利用谷氨酸等递质来激活元并协调进食，这听起来就像有大脑的有机体会做的事情。