評論
打印
Narrator:Listen to part of a lecture in a biology class.
獨白:聽下面一段生物學課上的演講。
Professor:Ok, now I want to talk about an animal that has a fascinating set of defense mechanisms.
教授:好的，現在我想講一講一種特別的動物，它有一套令人驚嘆的防御機制。
And that's the octopus, one of the unusual creatures that live in the sea.
它就是章魚，一種生活在大海之中的不凡之物。
The octopus is prey to many species, including humans, so how does it escape its predators?
章魚的天敵包括人類在內的很多物種的捕食者，那么，它是怎樣逃脫它的捕食者的呢？
Well, let me back up here a second.
好的，我先講些背景知識吧！
Anyone ever heard of Proteus?
有誰知道普羅透斯嗎？
Proteus was a God in Greek mythology who could change form.
普羅透斯來自古希臘神話中的一位海神。他可以變形，
He could make himself look like a lion or a stone or a tree, anything you wanted, and he could go through a whole series of changes very quickly.
使自己看上去像一頭獅子或者石頭、樹木，你們能想到的一切，并且他能夠在很短的時間之內完成變形。
Well, the octopus is the real world version of Proteus.
嗯，章魚是真正存在的現世版的普羅透斯。
Just like Proteus, the octopus can go through all kinds of incredible transformations.
和他一樣，章魚也能完成各種不可思議的變形。
And it does this in three ways:by changing color, by changing its texture, and by changing its size and shape.
同時，它可以用三種方式變形:改變顏色、改變紋理、改變大小和形狀。
For me, the most fascinating transformation is when it changes its color.
對我而言，最有趣的當屬改變顏色這項了。
It's a normal skin color, the one it generally presents, is either red or brown or even grey, and it's speckled with dark spots.
它沒有變色時的一般膚色，既可能是紅的，棕色的，甚至灰色的，體表點綴有許多黑色的斑點。
But when it wants to blend in with its environment to hide from its enemies, it can take on the color of its immediate surroundings:
但是，當它試圖和環境混同為一個顏色以趨避天敵時它馬上就能變成周圍景物的顏色:
the ocean floor, a rock, a piece of coral, whatever. Charles?
大海、巖石、珊瑚，什么都行。查爾斯，你有什么問題？
Student:Do we know how that works, I mean, how they change colors?
學生:我們知道這種變化的原理嗎？我的意思是，章魚是怎么做到的？
Professor:Well, we know that the reaction that takes place is not chemical in nature.
教授:嗯，我們肯定都知道，章魚變色本質上肯定不是依靠化學反應。
The color changes are executed by two different kinds of cells in the octopus' skin, mainly by color cells on the skin's surface call chromatophores.
這種顏色變化是由章魚皮膚組織中兩種不同類型的細胞完成的，主要是體表的叫做“色素體”的顏色細胞。
Chromatophores consist of tiny sacks filled with color dye.
“色素體”由許多細小的、裝有染色劑的色袋構成。
There might be a couple hundred of these color sacks per square millimeter of the octopus' skin, and depending on the species, they can come in as many as five different colors.
在章魚皮膚表面，每一平方厘米中大概有兩百個這樣的色袋，它們可以組合成五種不同的顏色。
Each one of these sacks is controlled by muscles.
每一個色袋都由肌肉控制。
If the muscles are relaxed, the sack shrinks, and all you see is a little white point.
如果肌肉在放松狀態下，色袋就縮小，你仔細觀察的話，就會發現這些色袋看上去像小白點一樣。
But if the muscle's contract, then the sack expands, and you can see the colors.
但是，如果肌肉一旦緊縮，色袋就會膨脹，你就會看到不同的顏色。
And by expanding different combinations of these color sacks to different degrees the octopus can create all sorts of colors. Yes,Vizebo?
當然，這些顏色也是靠色袋中不同顏色的染色劑組合成的。怎么了，維澤博？
Student:And just with various combinations of those five colors, they can recreate any color in their environment?
學生:就是通過這五種顏色的不同組合，章魚們就能變成和周圍環境一樣的顏色嗎？
Professor:Well, they can no doubt create a lot with just those five colors,
教授:嗯，利用這五種顏色，它們無疑可以變出很多很多的顏色出來，
but you are right, maybe they can't mimic every color around them, so that's where the second kind of cell comes in.
但你的問題很靠譜，可能它們并不能模仿它們周圍每一種顏色，所以就有了第二種細胞。
Just below the chromatophores is a layer of cells that reflect light from the environment, and these cells help the octopus create a precise match with the colors that surround them.
在“色素體”細胞之下有一個細胞層，它們負責反射環境中的各種光，
The colors from the color sacks are supplemented with colors that are reflected from the environment, and that's how they are able to mimic colors with such precision.
這種細胞幫助章魚完美地制造出和周圍環境一致的顏色。
So, that's how octopus mimics colors.
這就是為什么章魚能夠很精確地模仿周圍環境的顏色的原因。
But they don't just mimic the colors in their environment;
不過，它們不只是模仿它們生活環境中出現的顏色；
they can also mimic the texture of objects in their environment.
它們還能模仿它們生活環境中出現物品的紋理。
They have these little projections on their skin that allow them to resemble various textures. The projections are called papillae6.
它們的皮膚上有非常小的影射器，這些名為“觸頭”影射器幫助它們模仿各種紋理。
If the octopus wants to have a rough texture, it raises the papillae.
如果章魚想要紋理粗糙一些，它就啟動“觸頭”。
If it wants to have a smooth texture, it flattens out the papillae, so it can acquire a smooth texture to blend in with the sandy bottom of the sea.
如果它想要紋理光滑一些，它就把身上的“觸頭”變得平整，這樣它看上去就會很光滑，能夠和海底的沙地混淆起來。
So the octopus has the ability to mimic both the color and the texture of its environment.
總之，章魚有能力模仿它生活環境的顏色和質地。
And it's truly amazing how well it can blend in with its surroundings.
它這種熟練地與四周混同的隱蔽能力的確令人驚嘆。
You can easily swim within a few feet of an octopus and never see it.
哪怕你游到距離章魚幾尺遠的地方，你都可能看不到它。
Student:I read that they often hide from predators by squirting out a cloud of ink, or something like that.
學生:我聽說章魚經常噴出墨云之類的東西來躲避它的天敵。
Professor:Yes. The octopus can release a cloud of ink if it feels threatened.
教授:是的，章魚確實能夠在感到威脅存在的時候，釋放墨云。
But it doesn't hide behind it, as is generally believed.
但是它并像公眾想象的那樣，躲在墨云的后面。
Um, the ink cloud is ... it serves to distract a predator while the octopus makes its escape.
嗯，墨云的作用是…它主要是吸引天敵的注意力，以便章魚能夠在這時逃開。
Um, now there's a third way that octopus can transform themselves to blend in withor mimic their environment, and that's by changing their shape and size, well, at least their apparent size.
嗯，現在該談談第三種變形以隱藏于環境之中的方式了，即改變它們的形狀和尺寸。
The muscular system of the octopus enables it to be very flexible to assume all sorts of shapes and postures.
章魚的肌肉系統使得它們身體的柔韌性很強，能夠承擔各種形狀和姿態的張力。
So it can contract into the shape of a little round stone, and sit perfectly still on the seafloor.
所以它能夠將自身體積縮小到身邊的一塊小石頭的大小，并且安穩地躺在海底。
Or it can nestle up7 in the middle of a plant and take the shape of one of the leaves.
擺這種能力所賜，它也能夠蝸居于植物中，變成植物葉子的形狀。
Even Proteus would be impressed, I think.
我想，普羅透斯看到章魚的本事，也會吃驚的。
