It's in most items on grocery store shelves, from chips to breakfast cereals to beverages and even baby formula.

它存在於雜貨店貨架上多數物品中，從洋芋片到早餐麥片到飲料，甚至嬰兒配方奶。

Corn makes up around 20% of the nutrition for all humans worldwide,

玉米約佔全世界所有人類營養的 20%，

which makes it all the more surprising that corn, basically, shouldn't be edible at all.

這使得玉米基本上根本就不應該被食用這件事變得更驚人。

Of course, it's a completely legit human food now, but, to get there, corn has had to come a long way.

當然，它現在是完全可以給人類吃的食物，但為了達到這個目標，玉米走了很長遠的路。

There are a whole host of reasons why corn never should've been one of the plants we domesticated for food,

有一大堆的理由說明玉米為什麼本來不應該成為我們改良為食物的植物之一，

much less one of the top 10 staple crops on our plates.

更不用說成為我們十大主食作物之一了。

So, this is the unlikely story of an unassuming grass that became one of the heavy-hitters of the human diet.

所以說，這是一個不太可能發生的故事，講述一種不起眼的草如何成為人類飲食中的重頭戲之一。

The evolution of corn, also called "maize" in some parts of the world, is sort of a rags-to-riches story of the food world.

玉米在一些地方被成為玉蜀黍，其演變基本上是食世界從無到有的故事。

9,000 years ago, there was no corn as we know it.

9 千年前，還沒有我們所知的玉米。

The closest thing was a grass called "Teosinte" that grew in modern-day southern Mexico.

最接近的東西是一種稱為 Teosinte 的草，在現今墨西哥南部生長。

Teosinte produces cobs that are only about a sixth of the size of a modern ear of corn, with between 5 and 12 kernels per ear that break apart easily,

Teosinte 生產的玉米只有今日玉米的六分之一大，每穗有 5 至 12 容易掰開的玉米粒，

as opposed to modern corn's hundreds of kernels on a sturdy cob.

相比之下，現代玉米是在結實的棒子上，有數百顆玉米粒。

And those kernels were puny, tough, and literally indigestible, so the people who encountered Teosinte wouldn't have bothered with the kernels at all.

那些玉米粒又小又硬，基本上無法消化，所以那些人看到 Teosinte 的人根本就不會去吃這些玉米粒。

Because it's an annual grass that looks exactly nothing like modern corn,

因為它是一種全年生的草，看起來完全不像現代玉米，

for a very long time, scientists were flummoxed about where Teosinte fit in corn's family tree, and if it did at all.

科學家們有很長一段時間都感到困惑，關於 Teosinte 在玉米家譜中的位置，以及它是否應該在其上。

The debates over corn's true ancestry became so contentious that it became known as the "corn wars".

關於玉米真正祖先的辯論變得極有爭議，因此也被稱為玉米戰爭。

And that battle raged for nearly half a century, until additional genetic evidence showed, once and for all, that Teosinte alone was the ancestor of modern corn.

這場鬥爭持續了近半個世紀，直到更多遺傳學證據一次性地表明，Teosinte 是現代玉米的祖先。

And thus, a corn truce was called, and there was peace in the land.

因此，玉米戰爭休戰、土地上出現了和平。

Huzzah!

歡呼吧！

It's likely that Teosinte was first cultivated by humans around the Balsas River Valley of southern Mexico about 9,000 years ago.

Teosinte 很可能是在大約 9 千年前，墨西哥南部巴爾薩斯河谷附近一個小鎮被人類首次種植。

The Teosinte plant's stalks contain a sweet juice, kind of like sugar cane.

Teosinte 的莖稈含有一種甜汁，有點像甘蔗。

And archaeologists think that the stalks were the only reason Mesoamericans even cultivated it in the first place, and it had nothing to do with the kernels.

而考古學家認為，這些莖稈是中美洲人一開始種植了 Teosinte 的唯一原因，而它與玉米粒沒有任何關係。

Mesoamerican people would either chew on the stalks or juice them to ferment the sweet liquid into alcohol,

中美洲人會咀嚼莖稈或把它榨成汁，已將甜味液體發酵為酒，

because that's also a thing humans like to do with plants that contain sugary liquids.

因為這也是人類喜歡對含甜液植物做的一件事。

Genetic studies have provided evidence that corn came directly from Teosinte,

基因研究已經提供了證據，證明玉米直接來自於 Teosinte，

but it's less clear how the focus of cultivating the plant changed from stalk to kernel.

但不太清楚培養植物的重點是如何從莖部轉換到玉米粒。

What we do know is that it likely took just a few genetic changes to transform the hard-shelled Teosinte seeds into something that could nourish a civilization.

我們所知道的是，它很可能只花了一些基因變更就將有堅硬外殼的 Teosinte 種子轉變成可以滋養一個文明的東西。

Over time, the nomadic people who cultivated Teosinte started selecting the characteristics of the plants they liked best.

隨著時間推移，種植 Teosinte 的遊牧民族開始選擇他們最喜歡的植物特點。

Eventually, they set their sights on making the kernels as tender and plentiful as possible.

最終，他們把目光投向了使玉米粒儘可能地鮮嫩和豐富。

Each Teosinte kernel is covered in a rock-hard shell called "glume" that renders it basically inedible to humans.

每個 Teosinte 果粒都覆蓋堅硬的外殼，稱為 glume，讓它基本上不能為人類所食用。

The glume on the kernels of Teosinte keeps the seed intact as it travels through an animal's digestive system or over winters on the ground for months,

果粒上的 glume 讓種子在穿越動物消化系統時或是越冬數月時保持完整，

which is very useful for the plant, but not for whoever's trying to eat it.

這對植物非常有用，但對想吃它的人卻沒有用。

Ancient cultivators most likely began selecting seeds of Teosinte with the softest glume.

古代耕種者可能是由選擇glume 最柔軟的 Teosinte 種子開始。

And these days, that glume is the part of the corn on the cob that gets stuck between your teeth.

現代的 glume 是你在吃整根玉米時，卡在你牙齒間的東西。

Another big step in making corn out of Teosinte involved boosting the starch content in the kernels.

用 Teosinte 生長玉米所涉及的另一大步驟是提高果核中的澱粉含量。

Corn is about 73% starch by weight, which is much higher than Teosinte's kernels, and it's what makes corn a great source of fast calories.

玉米的澱粉含量約為 73%（按重量計算），這比 Teosinte 果核要高得多，而這正是使玉米成為快速熱量的重要來源。

Scientists still don't know a lot about the early cultivation of corn.

科學家們對玉米的早期種植仍然了解不多。

They're still investigating how corn developed multiple rows of kernels per ear and that solid cob you can really grab onto, among other things.

他們仍在研究玉米是如何在每個果穗上形成多排果核，以及可以真正抓住的堅實的玉米芯，還有其它東西。

All these changes show us that corn as we know it today would never have existed if people hadn't started tinkering with it.

所有這些變化向我們表明，如果人們沒有動手腳，我們今天所知道的玉米將永遠不會存在。

In fact, modern corn is completely unable to reproduce without human help because it doesn't have a mechanism for dispersing its seeds.

事實上，現代玉米在沒有人類幫助的情況下完全無法繁殖，因為它沒有傳播種子的機制。

So, thanks to the painstaking work of these ancient agriculturalists, humanity got a new, hard-won cereal crop.

因此，由於這些古代農學家的辛勤工作，人類獲得了來之不易的新穀類作物。

But even after corn's human architects had created a starchy, delicious grain, more work was necessary to make it as nutritious as possible.

但即使在玉米的人類建築師創造出一種含澱粉的美味穀物之後，仍需要做更多的工作才能使其盡可能有營養。

Because, remember, corn was never the best candidate for food in the first place.

因為，請記住，玉米從來都不是食物的最佳候選者。

To this day, corn is among the least nutritious staple crops.

時至今日，玉米是營養最差的主食作物之一。

Although it contains many of the nutrients we need, many of the nutrients aren't in a form that can be absorbed by the human body.

雖然它含有很多我們需要的營養物質，但很多營養物質並不是以人體可以吸收的形式存在。

But the pre-Colombian people of Mesoamerica who cultivated corn also invented a process called "nixtamalization",

但是種植玉米的中美洲前哥倫比亞人也發明了一種叫做「鹼法烹調」的過程，

which turned corn into more than just a side dish and allowed it to be the basis of millions of people's diets.

使玉米不再只是一道配菜，而是成為數百萬人飲食的基礎。

Nixtamalization involves cooking and then steeping the corn kernels in an alkaline solution of water and wood ash.

鹼法烹調涉及烹飪，然後將玉米粒浸泡在水和木灰的鹼性溶液中。

After the cooking process, the kernels are washed multiple times to remove the outer shell of the kernels as well as (the) excess alkaline solution.

烹飪過程結束後，內核會被多次清洗，以去除內核的外殼和多餘的鹼性溶液。

The result is a slurry called "nixtamal", which was ground into a soft dough that could be used to make things like tortillas and tamales.

結果是一種叫做 nixtamal 的漿液，它被磨成柔軟的麵團，可以用來製作玉米餅和玉米粉蒸肉等東西。

And it turns out that treating it with calcium hydroxide wasn't just making it taste better.

事實證明，用氫氧化鈣處理它不僅僅是讓它味道更好。

It was unlocking nutrients that would save lives.

它也正在解鎖將拯救生命的營養物質。

See, nixtamalization solved a lot of the nutritional problems with corn that we mentioned.

是這樣的，鹼法烹調解決了我們提到的玉米的許多營養問題。

It increases the dietary fiber, calcium, and the bioavailability of iron in the grain, meaning how much of it you can actually absorb.

它增加了穀物中的膳食纖維、鈣和鐵的生物利用度，也就是實際可以吸收的量。

But most importantly, it also increases the bioavailability of niacin, also called vitamin B3.

但最重要的是，它還增加了菸酸（也稱為維生素 B3）的生物利用度。

Niacin is a coenzyme, which means it's necessary for the functions of other enzymes in the body.

菸酸是一種輔酶，這意味著它對體內其它酶的功能必不可少。

It's instrumental in turning food into energy, making fats and cholesterol, and creating and repairing DNA, among other critical tasks.

它有助於將食物轉化為能量、製造脂肪和膽固醇、創造和修復 DNA 以及其它重要任務。

When Europeans came to Mesoamerica, they began eating corn and brought it back to Europe with them.

當歐洲人來到中美洲時，他們開始食用玉米並將其帶回歐洲。

But when it became widely eaten as a staple crop there, those growing and eating it skipped the nixtamalization part.

但是當它在那裡作為主要作物被廣泛食用時，那些種植和食用它的人跳過了鹼法處理部分。

As a result, they came down with a disease called "pellagra", which is a nasty combo of diarrhea, skin rashes, mouth sores, and dementia.

結果，他們患上了一種叫做「糙皮病」的疾病，這是一種腹瀉、皮疹、口腔潰瘍和癡呆症的嚴重組合。

And the culprit was a lack of niacin.

而罪魁禍首是缺乏菸酸。

Now, to be clear, it's perfectly fine to eat corn that hasn't been nixtamalized; we do it all the time.

現在，要點明，吃沒有經過鹼法處理的玉米是完全沒問題的，我們一直這樣做。

I mean, who doesn't love a corn on the cob?

我是說，誰不喜歡吃整根玉米呢？

Pellagra is only a concern if you aren't getting your niacin from any other parts of your diet, like, say, if you're only eating corn that wasn't nixtamalized.

只有當你沒有從飲食的任何其他部分獲取菸酸時，糙皮病才會成為一個問題，比如，如果你只吃沒有鹼化的玉米。

Which means, if the Mesoamericans who cultivated corn didn't also invent nixtamalization, eating mostly corn would have made them sick.

這意味著，如果種植玉米的中美洲人沒有發明鹼煮法，那麼主要吃玉米會讓他們生病。

So, it never could've become foundational to their diets, and, in turn, it never would've become such a big part of ours.

因此，它永遠不可能成為他們飲食的基礎，反過來，它也永遠不會成為我們飲食的重要組成部分。

It was against all odds that corn became edible, and then plentiful, and then yummy and nutritious.

玉米是在逆境中變得可以食用的，然後變得豐滿、然後好吃又有營養。

In that order.

按照這個順序。

So, the next time you're enjoying a taco, just take a moment to think about the many coincidences that brought that corn tortilla to your plate in the first place.

因此，下次享用塔可餅時，花點時間想想將玉米餅帶到盤子裡的許多初始巧合。

This video, and the fact that you may be feeling a craving for tortilla chips right now, was made possible thanks to our friends over at Patreon.

感謝我們在 Patreon 的朋友，讓這部影片以及你現在可能想吃玉米片的事實得以實現。

Our patrons support the work we do on this channel, and, in exchange, they get access to a bunch of perks.

我們的讚助人支持我們在這個頻道上所做的工作，作為交換，他們可以獲得大量福利。

For example, access to our exclusive Discord, bloopers from our video shoots, and our behind-the-scenes podcast.

例如，取得獨家 Discord 內容、影片拍攝 NG 片段花絮，以及我們的幕後播客。

So, if that sounds like a good deal, you can head over to patreon.com/scishow to sign up or just to learn more.

因此，如果這聽起來很划算，您可以前往 patreon.com/scishow 註冊或單純了解更多資訊。

Thanks for watching.

謝謝各位觀看。