A bubbling primordial soup in which life forms evolved

汩汩流淌的原始湯汁，生命形式在其中進化。

over millions of years and eventually crawled from the oceans onto the land.

經過數百萬年的時間，最終從海洋中爬到陸地上。

But new research suggests that instead... it might be the other way around!

但新的研究表明，相反... ...可能是另一種方式!

We've had the idea that life began in the oceans since the 1920s, when it was first

自20世紀20年代以來，我們就有了生命起源於海洋的想法，當時它被首次提出來。

put forward. This was cemented in our minds in the 1950s by the classic Miller-Urey experiment

提出的。20世紀50年代，米勒-尤里的經典實驗使這一點在我們的腦海中牢牢地記住了。

from which scientists hypothesized that the ocean-atmospheric cycle of early earth could

科學家據此推測，早期地球的海洋-大氣循環可能是一個很好的例子。

have been the perfect conditions to instigate life... but there were many unanswered questions.

有完美的條件來激發生命... 但有許多未解答的問題。

And since then, biogenesis researchers—those are the folks who study how life began—have

從那時起，生物起源研究者--那些研究生命如何開始的人--就有了。

been kind of obsessed with finding that key catalyst that would have brought chemical

痴迷於尋找關鍵的催化劑，這將帶來化學的

components together for the very first time. And research from the past several years has shown

組件首次結合在一起。而過去幾年的研究表明

that in some situations, that special sauce could have been UV radiation.

在某些情況下，這種特殊的醬料可能是紫外線輻射。

And while some teams HAVE been able to recreate the building blocks of life using UV light,

而一些團隊已經能夠利用紫外光重新創造生命的構件。

no one has yet been able to successfully perform these transformations in experiments that

目前還沒有人能夠在實驗中成功地進行這些轉換。

replicate seawater. Meaning that our whole 'life crawls onto land from the oceans' idea…

複製海水。意思是說，我們的整個 "生命從海洋爬上陸地 "的想法... ...

could be wrong? And here's another problem: while water

會不會是錯的？還有一個問題：雖然水

is a definite requirement for life on earth...the chemical properties of straight up H2O actually

是地球上生命的必然要求......直達的H2O的化學性質其實是

break down proteins. Including things that are made of protein—nucleic acids like DNA

分解蛋白質。包括由蛋白質-核酸組成的東西，如DNA

and RNA, the genetic material that holds the blueprint for all of life.

和RNA，是承載所有生命藍圖的遺傳物質。

Now these days, living cells tightly control their water balance to protect their insides from

現在，活細胞嚴格控制自己的水分平衡，保護自己的內臟不受傷害。

water degradation, but... how are proteins supposed to have formed IN a substance that

水降解，但是... ... 如何蛋白質應該已經形成在一個物質，

actively attacks and degrades them? Scientists now call this 'the water paradox'.

主動攻擊和降解它們？科學家們現在稱之為 "水悖論"。

And in 2009, we start to get some answers. John Sutherland and his team at Cambridge

而在2009年，我們開始得到一些答案。約翰-薩瑟蘭和他在劍橋的團隊

performed a series of experiments that successfully produced two of the four nucleotides that

進行了一系列的實驗，成功地產生了四種核苷酸中的兩種。

make up RNA, using just a really simple starting mix of basic chemicals that may have been

組成RNA，使用只是一個非常簡單的基本化學品的起始混合，可能已經

found on early earth. They exposed this mixture to UV radiation and presto change-o, nucleotides!

在早期地球上發現的。他們將這種混合物暴露在紫外線輻射下，然後預知變化------核苷酸!

Now key in these experiments is that these chemicals were all dissolved in water...

現在這些實驗的關鍵是，這些化學物質都溶解在水中...

but at very high concentrations. That means LOTS of the chemicals to just a little bit of water...

但濃度非常高。這意味著，LOTS的化學品 只是一點點的水... ...

like, really strong Kool-aid. This indicates that even though water may have been involved at

就像，真正強大的酷愛。這表明，即使水可能已經參與在

the beginning of life, it couldn't have been in a giant body of water, like an ocean,

生命的開始，不可能是在一個巨大的水體中，比如海洋。

where the concentration of those chemicals wouldn't be as strong.

在那裡，這些化學品的濃度不會那麼強。

For the chemicals to be in high enough concentrations AND to be exposed to sunlight (for that

要使化學品達到足夠高的濃度，並暴露在陽光下（為了達到這個目的），就必須要有足夠高的濃度。

crucial UV component), some scientists believe that this life-giving reaction had to have occurred in

關鍵的紫外線成分），一些科學家認為，這種賦予生命的反應必鬚髮生在。

environments like small pools. And next, building on the work that produced the

小水池等環境。而接下來，在工作的基礎上，產生了。

nucleotides, in 2015 Sutherland and his team were also able to produce the building blocks of

核苷酸，2015年，薩瑟蘭和他的團隊還能夠生產出構件的

proteins and fats. That's a big step, because now with nucleotides, and protein and fat

蛋白質和脂肪。這是一個很大的進步， 因為現在有了核苷酸， 蛋白質和脂肪。

pre-cursors... we've got all the moving parts needed to get life goin'!

前期... 我們已經得到了所有的活動部件 需要得到的生活布萊恩'！

And in 2020, other teams have found even further answers to the water paradox.

而在2020年，其他團隊已經找到了水悖論的更進一步的答案。

Researchers created conditions where almost-proteins could form and survive during wet-dry cycling.

研究人員創造了幾乎蛋白可以形成並在乾溼循環過程中存活的條件。

Which is exactly what it sounds like, the molecules are allowed to dry out for some

這正是它聽起來，分子被允許乾燥了一些。

time before they're exposed to water again. The researchers discovered this process is

時間，才會再次接觸到水。研究人員發現這個過程是

selective—only the molecules we would expect to see on an early earth withstood the cycling,

選擇性的--只有我們期望在早期地球上看到的分子才經得起循環。

and are actually shaped by it. This wet-dry cycling has even shown to essentially

並實際被其塑造。這種乾溼循環甚至顯示出本質上的

select for more complex combinations of nucleic acids inside little protective lipid bubbles

在小小的保護性脂質保麗龍中選擇更復雜的核酸組合。

that help them make it through dry periods... and scientists are starting to think this may

科學家們開始認為，這可能會幫助它們度過乾旱期...

be a precursor to something like a cell. All of this lends even more support to the idea that

是像細胞這樣的東西的前體。所有這些都更加支持了這樣的觀點

the body of water from which life may have sprung would be shallow, and prone to drying

水源淺，易乾涸

out from time to time. Imagine: all of life being descended from some stuff growing in

時不時的出來。想象一下：所有的生命都是由一些生長在地球上的東西衍生出來的。

a puddle. It's also worth mentioning here that not

一灘水。在這裡還值得一提的是，並不是說

everyone is in agreement. Although there are commonly agreed on necessary original ingredients,

大家都是一致的。雖然有普遍認同的必要原材。

some teams are still looking into deep sea vents as a possibility for the birthplace

一些研究小組仍在研究深海噴口作為誕生地的可能性。

of life, while others think hot springs are a likely contender.

的生命，而另一些人則認為溫泉是一個可能的競爭者。

And why is any of this important, anyway? Aside from answering existential questions

為什麼這些都很重要呢？除了回答存在的問題之外

about where the heck we come from, a better idea of how life originated here on Earth

關於我們從哪裡來，更好地瞭解生命是如何在地球上起源的。

gives us clues about what it might look like or where to look for it on other planets too.

給我們提供了關於它可能是什麼樣子的線索，或者也可以在其他星球上尋找它。

For example, in February of 2021, the Perseverance Rover successfully landed in Mars' Jezero Crater... which

例如，在2021年2月，"鍥而不捨 "號探測器成功降落在火星的傑澤羅火山口... ...

seems to have once been an ancient lake. And given all of this research, the crater is

似乎曾經是一個古老的湖泊考慮到所有這些研究，這個火山口...

now a prime suspect for signs of life on the red planet. Now it'll be years before the samples

現在是紅色星球上生命跡象的主要嫌疑人。現在，它將是多年前的樣本

return to Earth... but maybe—just maybe—they'll contain remnants of those proteins or lipids

返回地球... 但也許... 也許... 只是也許...

that would tell us if we aren't only planet that's ever hosted life.

這將告訴我們，如果我們不是唯一的星球 這曾經有生命。

Check out this video here for more on what early life on Earth might have been like, and if you

看看這段視頻，瞭解更多關於地球上早期生命可能是什麼樣子的，如果你

have questions about this origin of life scenario, let us know down in the comments below. Let

對這個生命起源的場景有疑問，請在下面的評論中告訴我們。讓

us know if you have another experiment you want us to cover and make sure you subscribe

如果你有其他實驗想讓我們報道，請告訴我們，並確保你訂閱了

to Seeker for more on ideas about life on other planets. As always, thank you so much for watching,

向探索者瞭解更多關於其他星球生命的想法。一如既往，感謝您的觀看。

and I'll see you in the next one.

下一次見。