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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，這烏賊會有一個可怕的問題，
because it's got this dying, thick culture of bacteria and it can't sustain that.
因為在它的體內，這些黏稠的細菌會不斷的增長，死亡，烏賊無法維持這些細菌的生長。
And so what happens is every morning when the sun comes up the squid goes back to sleep, it buries itself in the sand,
因此每天早上當太陽升起后，它將自己埋藏在沙中，進入睡眠，
and it's got a pump that's attached to its circadian rhythm,
而且它有一個與日夜周期同步的活泵，
and when the sun comes up it pumps out like 95 percent of the bacteria.
當太陽升起時，它將大約95%的細菌排出體外。
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.
既然細菌被稀釋了，這些小荷爾蒙分子也隨之消失，因此它們不發光了，但烏賊當然不在意。
It's asleep in the sand. And as the day goes by the bacteria double,
它正在沙中睡覺呢。當一天過去，這些細菌持續分裂生長，
they release the molecule, and then light comes on at night, exactly when the squid wants it.
它們釋放出這些分子，然后又開始在晚上發光，剛好就是烏賊需要光線的時候。
First we figured out how this bacterium does this,
我們先了解這些細菌為什么會有這種現象，
but then we brought the tools of molecular biology to this to figure out really what's the mechanism.
然后我們使用分子生物學的方法來研究真正的分子機制是什么。
And what we found -- so this is now supposed to be, again, my bacterial cell
我們發現了--再一次，想象這是我的細菌
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.
費氏弧菌有一種蛋白質，這個紅色的方塊--它是制造這小荷爾蒙分子的酵素。
And then as the cells grow, they're all releasing that molecule into the environment, so there's lots of molecule there.
當細胞生長時，他們全都釋放這個分子到環境中，因此環境里有一堆這種分子。
And the bacteria also have a receptor on their cell surface that fits like a lock and key with that molecule.
這些細菌的細胞表面，同時還有一種受器，與此分子的構造就如同鑰匙與鎖一般的吻合。
These are just like the receptors on the surfaces of your cells.
它們就如同你身體細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
當這些分子增加到一定的量時--也意味著這些細胞數量的增加，
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.
荷爾蒙與受器相結合，訊息開始向細胞內部傳遞，這個訊息告訴這些細胞開始表現此集體行為，并開始發光。
