Name: 【TED-Ed】為什麼藍鯨如此巨大？ Why are blue whales so enormous? - Asha de Vos
Uploaded: 2013-09-02T03:39:15.000Z
Duration: 5 min 21 s

進階形容詞比較級句型

They're at least two times as big as the biggest dinosaurs,

藍鯨的體型比最大的恐龍 至少大兩倍，

by feeding exclusively on tiny shrimp-like creatures called krill

我們稱為磷蝦的蝦狀小生物 就長得如此巨大。

that are no bigger than your little finger.

磷蝦的體型甚至不及你的小指頭呢。

seems to have driven the evolution of the blue whale.

似乎促使了藍鯨演化成現在的樣貌。

Basically, the whale accelerates towards a prey patch

基本上，藍鯨覓食時會加速游向獵物

To increase the capacity, its mouth expands.

為了增加容量，它的嘴吧會不斷延展擴張。

The special, accordion-like blubber layer

that extends from its snout to its belly button

enables the whale to engulf large quantities

the whale takes in 125% of its body weight

藍鯨都吞入相當於牠體重 1.25 倍的

the comb-like structure made of the same stuff

成分和我們的指甲及頭髮一樣，

It's pretty crazy that the blue whale's heart

藍鯨的心臟跟一台小型車一樣大

a child could crawl through its arteries,

牠的動脈大得足以讓小孩在裡頭爬行，

its tongue weighs as much as an elephant,

光是牠的舌頭，就跟一隻大象一樣重，

the whale could choke on a loaf of bread.

It's estimated that blue whales eat four tons of krill per day.

根據估計，藍鯨一天可以吃下四噸的磷蝦。

所獲取的能量 為其所消耗的九十倍。

Every mouthful of krill provides almost 480,000 calories,

每一口磷蝦，藍鯨都能從中攝取 四十八萬卡路里，

the same amount you get from eating 1,900 hamburgers.

甚至連陸地上最大的動物──大象，

than the largest living land animal, the elephant.

there's a point at which the legs of that animal

They need legs shaped like stout pedestals

In water, the situation is quite different.

Buoyancy counteracts the gravitational pull on the body

and their great bulk is therefore partially supported

有一部份是被水的浮力支撐住的。

So, the ocean is a great place for species

海洋可以說是提供了 想要長得大一點的動物

The other secret to their size is their diet.

飲食也在 龐大的身軀背後扮演重要的角色。

the whale's have specialized to catch enormous quantities

which provides the energy needed to grow so big.

提供其長到如此巨大所需的能量。

海洋像是 這些龐然大物的樂土。

Well, while lunge feeding may have allowed blue whales

這麼說好了， 雖然「衝刺進食」

by enabling them to feed efficiently in dense prey patches,

Scientists compared all the costs involved with lunge feeding

科學家將「衝刺進食」所需代價

to the energy gained from the krill they eat.

與從磷蝦身上獲取的能量 做了比較。

What they found is that when the whale's body increases in size,

the energy that body demands rises faster

than the extra energy they get from their food.

遠超過食物來源所能提供的量。

Feeding whales needs 15 times the energy required to remain still

「衝刺進食」所需能量 是維持靜止時的十五倍，

and 5 times more energy than used when swimming.

根據計算，使用「衝刺進食」的動物

that the largest a lunge feeder can grow is 33 meters,

Turns out blue whales have a lot to thank krill for:

看起來藍鯨可是欠了磷蝦不少人情：

that would not have been possible if krill were not so small.

藍鯨不可能發展出 這麼細緻的、演化上的環境適應。

It's incredible that these tiny creatures

have allowed blue whales to really push the limits

竟能使藍鯨挑戰 地球上生物體形的最大極限，