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But then if you think about it, the squid has this terrible problem
但是如果你再深入地想一下，这乌贼会有一个可怕的问题，
because it's got this dying, thick culture of bacteria and it can't sustain that.
因为在它的体内，这些黏稠的细菌会不断的增长，死亡，乌贼无法维持这些细菌的生长。
And so what happens is every morning when the sun comes up the squid goes back to sleep, it buries itself in the sand,
因此每天早上当太阳升起后，它将自己埋藏在沙中，进入睡眠，
and it's got a pump that's attached to its circadian rhythm,
而且它有一个与日夜周期同步的活泵，
and when the sun comes up it pumps out like 95 percent of the bacteria.
当太阳升起时，它将大约95%的细菌排出体外。
Now the bacteria are dilute, that little hormone molecule is gone, so they're not making light -- but of course the squid doesn't care.
既然细菌被稀释了，这些小荷尔蒙分子也随之消失，因此它们不发光了，但乌贼当然不在意。
It's asleep in the sand. And as the day goes by the bacteria double,
它正在沙中睡觉呢。当一天过去，这些细菌持续分裂生长，
they release the molecule, and then light comes on at night, exactly when the squid wants it.
它们释放出这些分子，然后又开始在晚上发光，刚好就是乌贼需要光线的时候。
First we figured out how this bacterium does this,
我们先了解这些细菌为什么会有这种现象，
but then we brought the tools of molecular biology to this to figure out really what's the mechanism.
然后我们使用分子生物学的方法来研究真正的分子机制是什么。
And what we found -- so this is now supposed to be, again, my bacterial cell
我们发现了--再一次，想象这是我的细菌
is that Vibrio fischeri has a protein -- that's the red box -- it's an enzyme that makes that little hormone molecule, the red triangle.
费氏弧菌有一种蛋白质，这个红色的方块--它是制造这小荷尔蒙分子的酵素。
And then as the cells grow, they're all releasing that molecule into the environment, so there's lots of molecule there.
当细胞生长时，他们全都释放这个分子到环境中，因此环境里有一堆这种分子。
And the bacteria also have a receptor on their cell surface that fits like a lock and key with that molecule.
这些细菌的细胞表面，同时还有一种受器，与此分子的构造就如同钥匙与锁一般的吻合。
These are just like the receptors on the surfaces of your cells.
它们就如同你身体细胞表面上的受器一般。
When the molecule increases to a certain amount -- which says something about the number of cells
当这些分子增加到一定的量时--也意味着这些细胞数量的增加，
it locks down into that receptor and information comes into the cells that tells the cells to turn on this collective behavior of making light.
荷尔蒙与受器相结合，讯息开始向细胞内部传递，这个讯息告诉这些细胞开始表现此集体行为，并开始发光。
