評論
打印
Narrator:Listen to part of a lecture in a Biology Class. The class has been learning about birds.
獨白:聽下面一段關于鳥類的生物學講座。本節課正在談論關于鳥類的知識。
Professor:Ok, today we are going to continue our discussion of the parenting behaviors of birds.
教授:好的，我們今天要繼續討論關于鳥類的哺育行為。
And we are going to start by talking about what are known as distraction displays.
首先我們來談談什么是分散注意力行為。
Now if you were a bird and there was a predator around.
現在，假定你們是鳥，而周圍正巧有只捕食者，
What are you going to do?
你們該如何是好？
Well, for one thing you are going to try to attract as little attention as possible, right?
首先，你會想要盡量不引起它的注意，對嗎？
Because if the predator doesn't know you are there, it is not going to try to eat you.
因為如果捕獵者不知道你在那兒，就不會來吃你。
But sometimes certain species of birds do the exact opposite when the predator approaches they do their best to try to attract the attention of that predator.
但有些鳥類的行為恰恰相反。當捕食者靠近的時候，它們想方設法去吸引其注意力。
Now why would they do that?
為什么這樣做？
Well, they do that to draw the predator away from their nests, away from their eggs or their young birds.
它們這么做是為了將捕食者從它們的巢和里面的幼鳥處吸引走。
And the behaviors that the birds engaging in to distract predators are called distraction displays.
這種調虎離山的高明策略就叫做分散注意力行為。
And there are a number of different kinds of distraction displays.
有很多種鳥類分散捕食者注意力的方法。
Most of the time, when birds are engaging in distraction displays they are going to be pretending either that they have injury or that they're ill or that they're exhausted.
大多數時間，當一鳥類要進行分散注意力行為的時候，它們會假裝受傷，或者是生病及非常疲憊。
You know something that'll make the predator thinks:Hum…here is an easy meal.
你知道,就是任何一種能讓捕食者認為嗯，這個獵物很好得手的感覺。
One pretty common distraction display was called the broken wing display.
一種比較常見的分散注意力的方法叫做斷翅法。
And in a broken wing display the bird spreads and drags the wings or its tail, and while it does that, it slowly moves away from the nests so it really looks like a bird with a broken wing.
在斷翅法中，一只鳥會散開它的翅膀和尾巴，拖著移動，它一邊這么做，一邊慢慢遠離自己的巢，看上去跟真的斷了翅膀一樣，
And these broken wing displays can be pretty convincing.
而且這斷翅會讓捕食者信以為真。
Another version of this kind of distraction display is where the birds create same impression of a mouse or some other small animals that running along the ground.
另外一種的分散注意力是鳥類制造了一種假象，好像有老鼠等小動物正在周圍。
A good example of that kind of display is created by a bird called the purple sandpiper.
這種行為的一個很好的例子是由一種叫做紫磯鷂的鳥類演繹的。
Now what's the purple sandpiper does is when a predator approaches, it drags its wings but not to give it the impression that its wings are broken but to create the illusion that it has a second pair of legs.
當捕食者在周圍時，紫磯鷂做的是拖著翅膀，但并不是要假裝翅膀斷了，而是為了制造一種有另外一雙腳的錯覺。
And then it raises its feathers, so it looks like it got a coat of fur.
它還會提升它的羽毛，看上去好像它披著一層絨毛。
And then it runs along the ground swirling left and right you know like running around a little rocks and sticks.
接著它繞著地上的小石頭、小木棍左右搖擺地跑來跑去，
And as it goes along it makes a little squeezing noises.
而且還會發出一些吱吱聲，
So from a distance it really looks and sounds like a little animal running along the ground trying to get away.
所以從遠處看，的確很像是小動物在地上逃跑的樣子。
Again to the predator, it looks like an easy meal.
同樣，這會讓捕食者覺得這是一頓能唾手可得的晚餐。
Now what's interesting is the birds have different levels of performance of these distraction displays.
有趣的是，鳥類的這種分散注意力行為有幾個不同的等級。
They don't give their top performance, their primetime performance every time.
它們并不是每次都拿出最高超的手段示人。
What they do is they save their best performances they're most conspicuous and most risky displays for the time just before the baby birds become able to take care of themselves.
它們在風險達到頂峰的時刻才會使用最厲害的方法，而當幼鳥即將出巢并且有了自理能力的時候，它們所使用的分散注意力的手段就會是冒險的。
And the time that way because that when that make the greatest investment in parenting their young.
因為保護幼鳥需要合理地投入精力。
So they are not going to put their best performance just after they laid their eggs because they have to invest that much more time and energy in parenting yet.
所以當鳥類剛下蛋后，它們不會花太多精力做分散注意力的行為，因為它們還有花費更多的精力去哺育幼鳥。
The top performance is going to come later.
高招要稍后再出。
Now you have some birds that are quite mature, are quite capable almost as soon as they hatch.
而現在一些幼鳥已經長的比較成熟了，也就是在被孵育出的一刻能夠自理，
In that case, the parent will put on the most conspicuous distraction displays just before the babies' hatch because once the babies are hatch they can pretty much take care of themselves, and then you have other birds that helpless when have hatch.
這種情況下，它們的父母將上演最顯眼的分散精力術，在幼鳥即將破殼之前，因為一旦它們破殼而出，就可以照顧自己了。
In that case, the parents will save the best performance until just before the babies get their feathers.
接著就會有其他鳥類來幫助它們孵育，這樣，父母就會將最好的分散注意力術上演到幼鳥長出羽毛。
