The surprising secrets of hummingbird flight - Kristiina J. Hurme and Alejandro Rico-Guevara

譯者: Camila Lin 審譯者: Yi-Ping Cho (Marssi)

And the clock starts...

即將開始......

now.

就是現在。

Did you miss it?

你看到了嗎？

It wasn’t some bug buzzing by or a weird trick of the light.

那不是什麼嗡嗡飛過的蟲子， 也不是什麼奇怪的光線把戲。

You just saw a hummingbird perform astonishing aerial acrobatics,

你剛剛看到的是一隻蜂鳥。

牠表演了驚人的空中特技： 在半空中吃午餐，

eat lunch in midair, pollinate a flower, and then escape a threat upside down—

為一朵花授粉，然後 倒著飛來逃離威脅。

all in a matter of seconds.

一切都發生在數秒之間。

So let’s slow down the action, and unpack each step in this blazing-fast feast.

讓我們放慢這些動作， 拆解這場如閃電般快速的視覺饗宴。

First up, their incredibly rapid flight.

首先，是牠們極其快速的飛行。

Hummingbirds typically beat their wings 30 to 40 times per second,

蜂鳥每秒通常能拍翅 30 到 40 下，

creating the high-frequency hum they’re named for.

這會產生高頻的嗡嗡聲， 牠們的英文名字也是由此而來。

To flap their wings at this speed,

為了以這種高速拍打翅膀，

hummingbirds have evolved giant pectoral muscles

蜂鳥進化出巨大的胸肌，

that comprise over a third of some species’ bodyweight.

有幾種蜂鳥的胸肌 甚至佔了體重的三分之一。

But the real secret to their fine-tuned flight is all in the wrist.

但這個精心調整的飛行方式， 奧秘在於牠們的腕關節。

Most birds only generate lift on the downstroke of each flap,

絕大多數的鳥，只能在每次 往下揮翅的時候產生升力，

while using the upward recovery stroke to set up their next wing beat.

而翅膀往上時， 則是為下一次的揮翅做準備。

Hummingbirds however, turn their wrists during the upstroke,

但蜂鳥在舉起翅膀時， 會轉動牠們的腕關節，

changing their wing’s angle to flap in a figure 8 pattern

改變翅膀的角度， 以 8 字型拍打翅膀，

that continually generates lift throughout their wingbeats.

如此一來，在整個拍翅的過程中， 就能持續產出升力。

Alongside their massive muscles, this special lift-producing technique

除了牠們巨大的肌肉， 這種特殊的騰升技術，

allows hummingbirds to achieve sustained hovering flight—

讓牠們能夠在空中懸浮，

an aerial feat no other bird can perform.

這是其他鳥類都無法做到的空中絕技。

Hovering lets hummingbirds slow to a stop almost instantly

懸浮能讓蜂鳥瞬間減速， 幾乎能立即停止行進，

and assess scenarios in midair.

並評估空中的各種可能情況。

Then, they can take off in any direction,

然後，牠們又能往任何方向起飛，

reaching speeds faster than a fighter jet, relative to the bird’s size.

將蜂鳥的體型納入考量， 牠們的速度比噴射戰鬥機更快。

And since they can beat each of their wings at different speeds and angles,

而因為牠們能以不同速度 與角度分別拍動翅膀，

the birds can perform incredible spins and turns

牠們能在向後飛或倒著飛的時候，

all while flying backwards or even upside down.

同時做出驚人的急轉或迴旋。

Of course, flying this way can be exhausting.

當然，以這種方式飛行很耗體力。

Hovering is one of the most energy intensive forms of movement

懸浮是動物王國中，

in the animal kingdom.

最耗能的移動方法之一。

And relative to their body size,

而考量到牠們的體型大小，

hummingbirds have the highest metabolic rates of all vertebrates.

蜂鳥的新陳代謝率 是脊椎動物中最高的。

This leads them to eat very frequently—

這讓牠們必須頻繁進食，

often consuming an average of four meals an hour while flying.

在飛行時，通常 15 分鐘就得吃一餐。

Fortunately, their hovering lets them eat at remarkable angles without perching,

幸運的是，牠們的懸浮技能 能讓牠們不必停下，

consuming food that would otherwise be impossible to reach.

以驚人的角度，成功吃到 以平常的方法搆不著的食物。

Using their long slender bills,

牠們能用細長的喙

they reach deep inside flowers and pump out nectar

深入花心，

再用牠們細長且有溝槽的舌頭， 將花蜜抽進口中。

with their thin grooved tongues.

This sugary liquid is a hummingbird’s most important energy source,

這種含糖液體 是蜂鳥最重要的能量來源。

and a single bird consumes six times its weight in nectar every day

如果把一隻蜂鳥每天數百頓的 簡餐加起來，牠們攝取的花蜜總量，

over hundreds of small meals.

高達自己體重的六倍。

Each of these sugary snacks also pollinates the flower being visited

在蜂鳥採食每一份含糖點心的時候， 牠們同時也會沾上花粉，

with pollen left on the bird from previous meals.

為下一朵被拜訪的花授粉。

That's just a rough idea of what hummingbirds can do in several seconds.

以上只是大略說明 蜂鳥在數秒內能做到什麼事。

But if we hang around a little longer,

但如果我們再待久一點，

we might see their aerial acrobatics put to a more dangerous test.

我們也許能看見，牠們的空中特技 受到更危險的考驗。

Hummingbirds keep track of which flowers they've recently drained,

蜂鳥總是密切關注著 牠們最近吸乾的花，

as well as those they plan to drain next.

還有那些牠們計畫要去採蜜的花。

And each bird will fight ruthlessly to defend this floral territory

每隻蜂鳥都會為了保衛花花領地 冷酷無情地戰鬥，

from their only real competition: other hummingbirds.

而牠們唯一真正的競爭者 即是：其他蜂鳥。

Using their spear-like bills and blindingly fast flight,

決鬥的兩隻蜂鳥用牠們尖矛般的喙，

以及令人眼花撩亂的快速飛行 在空中互相追逐，

dueling hummingbirds chase each other through the air,

aggressively stabbing and plucking feathers.

狠刺對方並啄去羽毛。

The bills of some species are specialized for fighting,

有些種類特化出戰鬥專用的喙，

with spiny tips, hooks, or even saw-like serrations.

它們有帶刺的喙尖、倒鉤， 甚至還有針狀的細齒。

Some hummingbirds employ these aerial fencing techniques

有些蜂鳥也將這些空中比武技術

to chase off larger birds like hawks and owls.

運用在驅逐鷹或貓頭鷹等更大的鳥上。

But the most extreme fights are between male hummingbirds

但最激烈的打鬥莫過於兩隻公蜂鳥

competing for flowers and females.

爭奪花朵與母蜂鳥。

Fortunately, these duels are rarely deadly.

幸運的是，這些決鬥幾乎都不會致命。

After 15 to 20 seconds, one bird will typically surrender—

在 15 到 20 秒後， 通常就會有一隻蜂鳥率先投降，

flying off to seek its breakfast elsewhere.

飛往別的地方尋找早餐。

After all this fighting, feeding, and flying,

在這些打鬥、覓食跟飛行後，

hummingbirds sometimes need to sleep off the day’s events

蜂鳥有時必須以休眠 這種溫和的冬眠形式，

in a mild form of hibernation called torpor.

恢復因白天一連串事件而消耗的體力。

Their hearts— proportionally the largest in the animal kingdom—

牠們的心臟重量佔全身體重的比例 是動物王國中最高的。

slow from 1,200 beats per minute to a mere 50.

而牠們一分鐘的心跳數 會從 1200 下逐漸降到僅有 50 下。

But when they wake up 4 to 7 hours later,

但在4到7小時後，等到牠們醒來，

their lightning-fast metabolism kicks back into gear.

牠們如閃電般快速的 新陳代謝率又會再度啟動。

With all this speed and strength,

蜂鳥擁有這種速度跟力量，

it’s no wonder the Aztecs revered these energetic birds

也難怪阿茲特克人 會認為這些精力充沛的鳥

as agents of the god of war Huitzilopotchli—

是戰神維齊洛波奇特利的使者。

a reminder that immense power can come in the smallest packages.

這也提醒著我們記得：微小的事物中， 也可能蘊藏著巨大的力量。