But for many other creatures, farts are no laughing matter.

但對於很多其他生物來說，放屁並不是什麼好笑的事情。

Deep in the bowels of the animal kingdom, farts can serve as tools of intimidation, acts of self-defense, and even weapons of malodorous murder.

在動物王國的內臟中，屁可以作為恐嚇的工具、自衛的手段，甚至是惡臭的殺人武器。

The smelliest parts in the animal kingdom aren't lethal, but they might ruin your trip to the beach.

動物王國中最臭的屁雖然不致命，但他們可能會毀了你的海灘之旅。

Seals and sea lions are well-known for having truly foul farts due to their diet.

海豹和海獅由於飲食的緣故，會放出非常臭的屁。

Fish and shellfish are incredibly high in sulfur.

魚類和貝類的硫含量非常高。

And during digestion, mammalian gut bacteria breaks down sulfur and amino acids containing sulfur to produce hydrogen disulphide, a gas with a smell resembling rotten eggs.

而在消化過程中，哺乳動物的腸道細菌會分解硫化物和含硫的氨基酸並生成二硫化氫， 一種聞起來像臭雞蛋的氣體。

Seals and sea lions can't help their funky flatulence, but some animals deploy their farts strategically.

海豹和海獅都沒辦法控制自己放出惡臭的屁，但有些動物放的屁卻是有策略性的。

Both the Eastern hognose snake and the Sonoran coral snake use a tactic called cloacal popping.

東部豬鼻蛇和索諾拉珊瑚蛇都會使用一種叫做「泄殖腔噴氣」的策略。

This involves sucking air into their cloaca — a hole used for urinating, defecating and reproduction— and then shooting it back out with a loud pop.

他們會先將空氣吸到泄殖腔，也就是一個用於排尿、排便和生殖的孔，然後再「碰！」的一聲噴氣出來。

These pops are no more dangerous than a sea lion's stench, but they are effective at scaring off would-be predators.

這個氣沒有比海獅的臭屁危險，但可以有效地嚇跑潛在的掠食者。

Meanwhile, the flatulence of beaded lacewing larvae are silent and deadly.

另一方面，毛蜻蛉科幼蟲的屁是無聲又致命的。

Their farts contain a class of chemical known as allomone that has evolved specifically to paralyze termites.

他們的屁中含有「利己傳訊素」，是一種專門用來麻痺白蟻的化學物質。

In fact, this allomone is so powerful, a single fart can immobilize multiple termites for up to three hours, or even kill them outright.

事實上，利己傳訊素的毒性非常強，只要一個屁就能讓一群白蟻長達三個小時無法動彈，甚至是直接殺死他們。

Either way, these toxic farts give beaded lacewing larvae to devour prey up to three times their size.

但不管哪種方式，這種毒屁讓毛蜻蛉科幼蟲有很多時間來吞食牠們體型三倍大的獵物。

For some other animals, however, holding farts in can be deadly.

然而，對有些動物而言，把屁憋住可是會致命的。

The Bolson pupfish is a small freshwater fish found in northern Mexico.

灰鱂是一種分布在墨西哥北邊的小型淡水魚。

These fish feed on algae and other small organisms in the sediment.

這些魚以沉澱物中的藻類和其他小生物為食。

But during the hottest days of the summer, this algae produces a lot of gas.

但在非常炎熱的夏日裡，這些藻類會在牠們的腹中產生大量氣體。

If a pupfish doesn't fart this gas out, it becomes buoyant — making it easy prey for passing birds.

如果灰鱂沒有將這些氣體排出來，牠們就會浮到水面上，並成為路過鳥類的獵物。

And it isn't just predators they have to worry about.

而牠們要擔心的可不只有掠食者。

Excessive gas buildup can actually burst their digestive systems.

堆積過量的氣體可能還會將牠們的消化系統撐破。

Researchers have found groups of several hundred dead pupfish that failed to fart for their lives.

研究人員曾發現數百隻死掉的灰鱂，全都是因為沒有把屁放出來而喪命。

Fortunately for humanity, animal farts can't directly harm a human — outside making us lose our lunch.

幸運的是，對人類而言，動物的屁並不會直接傷害到人類—除了影響我們的食慾以外。

But in the right circumstances, some animal flatulence can create surprisingly dangerous conditions.

但在特殊情況下，有些動物的屁會造成意想不到的危險。

In the fall of 2015, a tripped smoke alarm forced a plane to make an emergency landing.

在 2015 年的秋天，曾有一架飛機因為煙霧警報器響而緊急迫降。

Upon further inspection, officials found that there was no fire — just the burps and farts of over 2,000 goats being transported in the cargo bay.

經過進一步的調查，調查人員發現飛機並沒有起火，但貨艙裡充滿了 2000 多隻山羊所放出的嗝和屁。

The change in air pressure had caused them to pass gas en masse.

因為氣壓的變化，導致他們排出了大量的氣體。

Thankfully, this story of farting goats had relatively low costs.

幸好這個山羊放屁的故事並沒有讓人付出很大的代價。

But the most dangerous flatulence in the world may actually come from a similarly unassuming mammal: the humble cow.

但世界上最危險的屁實際上可能來自與羊同樣平易近人的動物：不起眼的牛。

There are nearly one billion cows in the world, most of them raised specifically for milk and meat.

世界上有將近 10 億頭牛，大部分都是為了生產牛奶和牛肉而飼養的。

Like goats, cows are ruminants, which means their stomachs have four chambers, allowing them to chew, digest and regurgitate their food multiple times.

和羊一樣，牛是反芻動物，代表牠們的胃有四個胃室來幫助牠們反覆咀嚼、消化及反芻食物。

This process helps them extract extra nutrients from their food, but it also produces a lot of gas.

這個過程能幫助他們從食物中獲得更多營養，卻也因此製造出很多氣體。

This is particularly troubling because one of the gases cows emit is methane, a major greenhouse gas that contributes heavily to global warming.

這是個問題，因為牛放出的其中一種氣體是甲烷—一種導致全球暖化的主要溫室氣體。

One kilogram of methane traps dozens of times more heat in the atmosphere than one kilogram of carbon dioxide.

一公斤的甲烷在大氣中吸收的熱，是一公斤二氧化碳吸收的幾十倍。

And with each cow releasing up to 100 kilograms of methane every year, these animals have become one of the biggest contributors toward climate change.

而每隻牛每年會排放多達 100 公斤的甲烷，這讓他們成為造成氣候變遷最大的元凶之一。

So while other animals may have louder, fouler, or even more toxic farts, cow flatulence may be the most dangerous gas ever to pass.

所以說，雖然其他動物的屁可能更大聲、更臭，甚至更毒，但牛的屁大概是有史以來最危險的屁。

Everybody farts. Yes, even you!

任何人都會放屁。沒錯，包括你也是！

So why exactly do we humans pass gas?

所以為什麼人類會放屁呢？

Get the fact about flatulence with this video.

藉由觀賞這部影片來瞭解腸胃脹氣的知識吧！