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把蜂鸟放到风洞前会发生什么 – 译学馆
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把蜂鸟放到风洞前会发生什么

What Happens When You Put a Hummingbird in a Wind Tunnel? | Deep Look

蜂鸟总是饥肠辘辘。身为地球上最小的鸟类 它们的新陈代谢频率
Hummingbirds are ravenous. These tiniest of birds have the highest metabolism
比其他任何恒温动物都要高
of any warm blooded animal.
而且它们主要以花蜜为食
And they’re fueled by flower nectar.
为了吃到花蜜 蜂鸟发展出了任何其他鸟类都不曾拥有的本领
To get it, they’ve developed skills no other birds have.
它们能倒飞 能长时间悬停
They can fly backwards and hover for long stretches of time.
蜂鸟的喙能保持稳定 像外科医生手中的手术刀
Their beaks stay steady like a surgeon’s scalpel,
但它们的翅膀振动频率非常快 达到80次/秒
but their wings beat furiously, up to 80 times a second.
而且蜂鸟能在风中 甚至雨中悬停
And they can hover in wind. In rain even.
大多数蜂鸟比五分硬币还轻
Most of these birds weigh less than a nickel.
没准一阵风就能把它们刮跑
You’d think they’d get blown away.
那么 蜂鸟是怎么办到的?
So how do they pull it off?
加大伯克利分校的科学家们将蜂鸟带进实验室 进行详细观察
Scientists at UC Berkeley brought hummingbirds into the lab for a closer view.
首先 野生蜂鸟必须接受训练 每次一只 从装满糖水的
First, the wild birds had to be trained, one at a time, to feed from an artificial flower
人造花朵中进食
filled with sugar water.
蜂鸟的翅膀拍打起来与直升飞机的旋翼转动时一样速度奇快 肉眼难以看清
Hummingbird wings buzz like helicopter blades – too fast for the naked eye to see.
但通过高速摄像机–1000帧/秒–的记录 科学家们
But by recording them with a high-speed camera – at 1000 frames a second — scientists
能看清蜂鸟双翼的每次运动。他们终于能详细观察悬停的过程了
can see the individual wing movements. They can actually see how hovering works.
大部分鸟类通过上下拍动翅膀飞行。但蜂鸟则前后拍动翅膀 双翼以“8”字轨迹运动
Most birds flap their wings up and down to fly. But hummingbirds move their wings backward
形象地说 像在划桨一样
and forward in a figure eight movement, like oars.
在向上划和向下划的过程中产生了升力 蜂鸟得以
This generates lift during the upstroke and the downstroke, which helps hummingbirds stay
保持平衡 不会忽高忽低
stable, instead of bobbing up and down.
但是当遇到糟糕天气的时候 蜂鸟要如何应对呢?
But how would a hummingbird respond when the weather gets rough?
为找到答案 科学家们将蜂鸟放进风洞并开始记录
To find out, the scientists moved the hummingbird into a wind tunnel and began recording.
风从笼子右侧吹入– 速度达到20英里/时(译注:约等于32千米/时)
The wind is coming from the right side of t he cage – up to 20 miles per hour.
蜂鸟必须在风中飞行才能吃到糖水
The hummingbird must fly into the wind to get the sugar water.
这段高速录影展示了蜂鸟如何在气流吹来的方向扭动身体
This high-speed footage shows how it turns and twists its body in the direction of the
通过翅膀保持控制 并把尾巴当舵以保持稳定
air flow, while using its wings for control and its tail like a rudder to stay steady.
即使下雨也无法阻止蜂鸟进食
Even rain can’t stop the hummingbird from feeding.
看到它是如何甩掉身上的雨滴了吗?像淋湿的狗一样
See how the bird shakes off drops of water from its body, like a wet dog?
蜂鸟必须不停进食。它们每天需要消化与体重相等的花蜜
The birds can’t afford not to eat. They have to consume their weight in nectar
才能生存
every day to survive.
花朵也需要蜂鸟。蜂鸟在进食的过程中 起到传播花粉的作用
And the flowers need them too. As they eat, hummingbirds spread pollen from plant to plant.
这便是共生现象–鸟与花之间的互利互惠关系
It’s a symbiosis – a two-way street between a bird and a flower.
这些微小的飞行机器已经进化出了独特的生存技巧
These tiny flying machines have evolved ways to hold up their end of the bargain,
风雨无阻
rain, wind or shine.

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