Those hefty molars helped us grind up fibrous veggies.

那些碩大的臼齒幫我們磨碎了纖維素。

Then, around 1 million to 2 million years ago,

那麼，大約在100萬至200萬年前。

we invented cooking,

我們發明了烹飪。

which softened food so we didn't need to chew as much.

它使食物變軟，所以我們不需要咀嚼那麼多。

That put wisdom teeth out of a job.

這讓智齒失去了工作。

Around 10,000 years ago,

大約在一萬年前。

we began to farm and cook our food even more.

我們開始耕種，並更多地烹飪我們的食物。

With less work to do, our powerful jaws shrank,

隨著工作的減少，我們有力的下巴也縮了起來。

making it harder for those extra teeth

讓那些多餘的牙齒更難長出來

to fit in our mouths.

以適應我們的嘴。

And today, we suffer the consequences.

而今天，我們卻要承受這樣的後果。

Gum infection, tooth decay, even tumors.

牙齦感染，蛀牙，甚至腫瘤。

But, unfortunately, annoying extra molars

但是，不幸的是，惱人的多出的臼齒。

aren't the only way evolution screwed us over.

並不是只有進化論才把我們搞垮的。

All primates, including humans, have something in common:

所有的靈長類動物，包括人類，都有一些共同點。

We have incredibly bony feet.

我們有一雙骨感十足的腳。

Each one contains 26 bones.

每個人都有26根骨頭。

Together, that's almost a quarter

加在一起，差不多有四分之一

of all the bones in our body.

在我們身體的所有骨骼中。

Now, this foot design makes perfect sense

現在，這個腳的設計很有意義

to our ancient primate ancestors,

我們的遠古靈長類動物的祖先。

because all those tiny moving parts

因為所有這些微小的運動部件

made their feet flexible enough to cling to branches.

使它們的腳靈活得可以緊緊抓住樹枝。

But here's the problem:

但問題就在這裡。

Once our ancestors left the trees

一旦我們的祖先離開樹

and started walking upright,

並開始直立行走。

we needed a more rigid, stable foot to balance

我們需要一個更堅硬，更穩定的腳來平衡

and propel ourselves from one step to the next.

並推動我們自己從一個臺階走向另一個臺階。

We didn't lose a single bone.

我們沒有失去一根骨頭。

The result? Our feet are too flexible,

結果呢？我們的腳太靈活了。

and they can easily twist the wrong way,

而且他們很容易扭錯方向。

which leads to all sorts of foot-related ailments,

導致各種與腳有關的疾病。

like sprains, stress fractures, and tendonitis.

如扭傷、應力性骨折和肌腱炎。

If that's not bad enough,

如果這還不夠糟的話

walking upright also messed up our spine.

直立行走也把我們的脊柱弄得亂七八糟。

In animals that walk on all fours,

在四肢行走的動物中。

the spine arches like a bridge,

脊樑拱起如橋。

which helps support the weight

這有助於支持重量

of their internal organs dangling beneath.

他們的內臟在下面垂著。

Then, 6 million years ago,

那麼，600萬年前。

our ancestors first stood up

吾祖先立

and forced that smooth arch into an S shape.

並將那光滑的拱形逼成S形。

The top is curved outward to support the weight of our head,

頂部向外彎曲，以支撐我們頭部的重量。

and the bottom is curved inward

而底部向內彎曲

to keep our torso in line with our feet,

以使我們的軀幹與腳步保持一致。

so we can balance.

所以我們可以平衡。

Unfortunately, this design isn't very sound.

可惜的是，這種設計並不是很完善。

That bend in our lower back

腰部的彎曲

puts a tremendous amount of pressure on our backbone.

給我們的骨幹帶來了巨大的壓力。

So it's no wonder that 60% to 70% of people worldwide

所以，難怪全球有六七成的人... ...

experience lower-back pain sometime in their life.

在他們的一生中的某個時候會經歷下背部疼痛。

Speaking of pain, let's talk about

說到疼痛，我們來談談

getting hit in the testicles.

被擊中的睪丸。

Unlike most of your organs,

不像你的大部分器官。

they hang outside your body,

他們掛在你的身體外面。

so they aren't protected by muscles, fat, and bone,

所以他們沒有被肌肉、脂肪和骨骼保護。

which makes them a prime target for incoming soccer balls.

這使得他們成為傳入足球的主要目標。

So why are we, and many other mammals,

那麼，為什麼我們，還有很多其他的哺乳動物。

stuck with such a risky arrangement?

受困於這樣的風險安排？

Well, it turns out, sperm are healthiest

原來，精子是最健康的。

when they're stored in a cool place.

當它們被存放在陰涼的地方時。

So we hold them as far away from the body as possible

所以我們拿著它們的時候要儘可能的遠離身體

to keep them a few extra degrees below body temperature.

讓他們的體溫多低幾度。

And humans have it especially bad.

而人類的情況特別嚴重。

Since we walk upright, gravity pulls

由於我們是直立行走，重力會拉動

on our exposed testes,

在我們裸露的睪丸上。

which can lead to a potentially excruciating condition

這可能導致一個潛在的痛苦的狀況

called inguinal hernia.

稱為腹股溝疝氣。

And while this might feel like the worst thing ever,

雖然這可能會讓人感覺是最糟糕的事情，

other evolutionary quirks can be deadly.

其他的進化怪癖可能是致命的。

Take the dangerous way our throat is structured.

以我們的喉嚨結構的危險方式。

It contains two important tubes,

它包含兩個重要的管。

the trachea, or windpipe, where air travels,

氣管，即氣管，空氣流通的地方。

and the esophagus, where food travels.

和食道，食物在那裡流動。

These pipes are nestled so close together,

這些管子是如此緊密地依偎在一起。

it's just plain stupid.

這只是普通的愚蠢。

Because when you swallow,

因為當你吞下。

food can slip into your windpipe and block airflow,

食物會滑入氣管，阻塞氣流。

causing you to choke or suffocate.

導致你窒息或窒息。

Every year, about 5,000 Americans die

每年約有5,000名美國人死亡

by choking on food.

因噎廢食。

Meanwhile, other animals have a more sensible arrangement,

同時，其他動物有更合理的安排。

where their windpipe and esophagus

氣管和食管處

are far away from each other.

是相距甚遠。

So, why don't we have that setup?

那麼，為什麼我們沒有這種設置呢？

Well, by sticking the pipes together,

好吧，通過把管子粘在一起。

we can open up extra space in our throats,

我們可以打開額外的空間 在我們的喉嚨。

which acts like an echo chamber

如同迴音室

to amplify sound to help us talk.

來放大聲音，幫助我們說話。

But evolution doesn't always come with a silver lining.

但進化並不總是一帆風順的。

In the 18th century, millions of sailors

在18世紀，數以百萬計的水手

suffered from a horrible disease called scurvy.

患上了一種可怕的疾病，叫壞血病。

Their gums would swell and bleed

他們的牙齦會腫脹出血

as their skin disintegrated and their brains decayed.

因為他們的皮膚在分解，大腦在腐爛。

The culprit?

罪魁禍首？

Away from shore for months on end,

連續幾個月遠離海岸。

the sailors had no access to fresh fruits and vegetables,

水手們無法獲得新鮮水果和蔬菜。

key sources of vitamin C,

維生素C的主要來源。

which plays a crucial role in how our body

這對我們的身體起著至關重要的作用

repairs damaged tissue, bone, and nerves.

修復受損的組織、骨骼和神經。

Now, humans, along with other apes,

現在，人類與其他猿類。

guinea pigs, some bats, birds, and fish,

豚鼠，一些蝙蝠，鳥類和魚類。

are the only animals that would ever have this problem,

是唯一會出現這種問題的動物。

because everyone else can produce their own vitamin C,

因為別人都可以自己生產維生素C。

no oranges needed.

不需要橙子。

Meanwhile, humans have a gene mutation

同時，人類有一個基因突變

that prevents us from doing the same.

阻止我們做同樣的事情。

Which normally wouldn't be a problem

這通常不會是一個問題

for our ancient, fruit-eating ancestors,

為我們古老的、吃水果的祖先。

who didn't trap themselves on ships

船大不壓死人

without fresh fruit for months.

幾個月沒有新鮮水果。

Now, there doesn't seem to be any benefit to this mutation,

現在看來，這種變異並沒有什麼好處。

which just goes to show,

這正好說明。

evolution isn't always helpful.

進化並不總是有用的。

In fact, it can make life a whole lot worse.

事實上，它可以讓生活變得更糟糕。