Humans eat lots of weird stuff, but one thing we almost never eat is poop,

人類會吃很多怪東西，但不包括大便，

either because we're naturally grossed out by it, or because we've learned that poop contains nasty pathogens.

要不是因為我們自然地覺得排泄物很噁，就是知道其帶有骯髒的病原體。

But for lots of animals, feces is a regular part of the menu.

但對大多數動物來說，糞便是常吃的菜色。

That's partly because poop isn't necessarily as dangerous as we think.

這是因為糞便其實不如我們想像的危險。

While poops from sick individuals can contain disease-causing bacteria, viruses, and parasites — and contaminate anything they touch —

雖然病人的糞便可能有病原細菌、病毒、寄生蟲，還會污染觸及的一切，

healthy poops are usually just water, harmless bacteria, undigested food, and some metabolic waste and dead cells.

健康的大便其多半只含有水、無害細菌、未消化的食物、一些新陳代謝排洩物和死去的細胞。

Poison control centers consider accidental ingestion of poop, human or otherwise, to be minimally toxic.

毒物控制中心認為，誤食人類或動物糞便是鮮少有害。

And doctors even prescribe poop pills from healthy people to combat hard-to-treat gut infections.

醫生甚至會開糞便藥丸處方簽，利用健康人士的糞便醫治棘手的內臟感染。

And because the digestive process doesn't usually manage to suck all the nutrients out of food, poop is nutritious.

而且由於消化過程通常不會吸收所有食物營養，剩餘的會殘存於糞便。

Herbivores, for example, leave a third of food nutrients in their poop.

舉例來說，草食動物的糞便殘存三分之一的食物營養。

As a result, animals like dung beetles and flies subsist almost entirely on nutrients from the poop of other animals.

因此糞金龜和蒼蠅這類的動物以其他動物的糞便維生。

And for thousands of years, humans have built toilets over pigsties because pigs can get almost all of their nutrition from human poop.

而千年以來，人類都將糞坑設立於豬圈上方，因為豬隻能夠從人類糞便獲取所需營養。

And while some dogs will snarf down pretty much any poop they come across,

雖然有些狗一看到任何糞便就開吞，

lots of dogs will actually use their keen noses to sniff out fresh poop that has specific vitamins or enzymes they're craving.

許多狗其實會先用靈敏的鼻子分辨含有特定維他命和酶的新鮮糞便，這些才是牠們想要的。

And some animals regularly extract leftover nutrients from their own poop.

而有些動物則會定期從「自己」的便便吸收殘存營養。

For example, when gorillas feed on the hard seeds of the Dialium tree,

舉例來說，大猩猩吞下摘亞木的種子時，

their gut bacteria soften the tough seeds but don't extract many nutrients.

牠們的腸道細菌將種子硬殼軟化，但並不會吸收到太多營養。

So when times are tough, gorillas will often eat their excrement to extract the seeds' full complement of fat and sodium.

所以在食物短缺時，大猩猩往往會吃自己的排洩物好吸收種子完整的油脂和納。

And when the southern cassowary eats cassowary plums,

還有，如果鶴鴕吃下灰乳木，

the fruits are so big and the bird's digestive tract is so short that the cassowary poops out whole chunks of the fruit;

由於牠們的消化管太小，果實則太大，鶴鴕會排洩出整顆果實，

it then turns around and picks them out to eat, and digest, again.

然後回過頭再次吞下肚，重新消化。

Other animals absolutely have to eat their own poop.

其他一些動物則是「必須」吃自己的糞便。

For example, rabbits eat lots of the same foods that ruminants like cows do,

舉例來說，兔子和其他反芻動物 (例如牛) 吃一樣的食物，

but while cows have long, complex digestive tracts that give the microbes inside time to break down the tough plant cells,

不過牛有又長又複雜的消化道，給予腸道細菌足夠時間分解堅硬的植物细胞，

rabbits have much shorter guts.

而兔子的腸道卻短得多。

So, after a yummy plant meal, they poop a soft mucus-covered cluster that contains the partially digested food and the microbes in charge of digesting it.

所以在享用完一頓全素佳餚後，牠們拉出覆有黏液的柔軟團塊，其中含有部分消化的食物和負責消化的微生物。

Then they gobble the whole package back up in order to recover the nutrients and bring the microbes back into their guts.

然後整組原封不動吞回肚，重拾營養和腸道微生物。

Finally, the rabbit poops real rabbit poop.

到最後，兔子才會真的拉出便便。

Koalas, too, must eat their own poop.

無尾熊也必須吃自己的糞便。

Or at least their own mom's poop.

或至少，吃牠們媽媽的糞便。

They have a specialized diet of eucalyptus leaves,

牠們的主食是尤加利葉，

which are both fibrous and toxic, and koala babies aren't born with the specialized bacteria needed to break it down.

這種葉子纖維多，而且有毒，無尾熊寶寶沒有能夠分解尤加利葉的特殊益生菌。

So for several weeks, the baby just eats pap:

所以寶寶出生後幾個月都只吃一種流質食物 ——

a soft, green poop chock-full of those bacteria that the mom makes special for her little one.

軟呼呼的綠色糞便，裡頭含有無尾熊媽媽給小無尾熊的「細菌特餐」。

Pap both supplies nutrients and gives the baby the microbes it needs to digest its future food.

這種流質食物能供給寶寶營養及未來消化所需的微生物。

As baby food goes, this number 2 is second to none.

以寶寶食物而言，這種食物營養滿分！

Feeding your baby poop is a pretty strange strategy.

餵自己的小孩吃大便是蠻怪的。

But feeding your baby to a predator is an even stranger one.

不過把小孩餵給掠食者就更怪了。

When a quokka mom gets cornered, she sometimes ejects a helpless joey from her pouch and runs the other way.

短尾矮袋鼠媽媽窮途末路時，會將無助的幼獸從袋中投出，然後往反方向逃跑。

And this actually sort of makes sense, she has a spare!

但這種行為其實說得通，因為牠不只有一個孩子！