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  • This week of SciShow is supported by Brilliant!

    本週的 SciShow 是由 Brilliant 贊助!

  • To learn more, go to Brilliant.org/SciShow.

    前往 Brilliant.org/SciShow 了解更多資訊。

  • I don't know if you've noticed, but animals kind of need oxygen.

    我不知道你有沒有注意到,但動物都需要氧氣。

  • That's because animals generally get their energy from cellular structures called mitochondria,

    這是因為動物通常在粒線體中獲得能量,

  • and those processes require oxygen to work.

    而那些過程需要氧氣才能運作。

  • So if somebody stole all of the Earth's O2, things would end pretty quickly around here.

    因此,如果有人偷走地球上所有的氧氣,一切很快就會在此結束。

  • Except, as it turns out, there are at least some animals that would be perfectly fine.

    其實,至少有些動物還是過得很好。

  • Because in 2010, scientists published a paper announcing

    因為在 2010 年,科學家發表了一篇論文,其表示

  • that they'd found three species of them that straight-up don't need oxygen!

    他們發現三種完全不需要氧氣的物種!

  • Now, to be clear, not all life needs oxygen.

    明確來說,不是所有生命都需要氧氣。

  • There are plenty of single-celled microbes that are anaerobic,

    有很多單細胞微生物是厭氧性的,

  • meaning they can survive just fine without the stuff.

    代表它們不用氧氣也能過得很好。

  • Instead of oxygen, these organisms can use other molecules like sulfate or nitrate.

    與其利用氧氣,這些生物可以利用其他分子,如硫酸鹽或硝酸鹽。

  • But for years, scientists thought a system like that wouldn't work for animals,

    但長年下來,科學家認為這種系統不適用於動物上,

  • since their complex, multicellular bodies have higher energy requirements.

    因為它們的身體複雜、細胞又多,有更高的能量需求。

  • Instead, they thought animals needed the more efficient energy production that takes place in mitochondria.

    相反的是,他們認為動物在粒線體生產能量時,需要更有效率的方式。

  • And then came that 2010 paper.

    回到 2010 年的那份論文。

  • This discovery happened in the L'Atalante basin,

    此發現在阿塔蘭特盆地,

  • three thousand meters below the surface of the Mediterranean Sea.

    地中海海面三千公尺以下。

  • L'Atalante is a deep hypersaline anoxic basin,

    阿塔蘭特盆地是深層高鹽無氧盆地,

  • meaning it's super salty and completely devoid of oxygen.

    意思就是它超鹹,而且完全沒有氧氣。

  • It's the kind of place you wouldn't expect to find animals.

    這種地方你不會認為有動物。

  • And indeed, when a research team visited three times between 1998 and 2008,

    確實,研究團隊在 1998 年至 2008 年間進行 3 次調查,

  • that's generally what they saw.

    那也是他們所看到。

  • They did find a lot of single-celled organisms living in the basin,

    他們確實發現很多單細胞生物生活在盆地中,

  • but most of the animals they saw were dead,

    但看到的大多數動物都死了,

  • the result of a so-calledrain of cadaversfrom oxygenated waters above.

    因為上方含氧水導致出所謂的「屍體雨」。

  • Most of the animals, but not all of them.

    是大部分動物,但不是所有。

  • Because the team also found an unusually high abundance of tiny, sediment-dwelling animals

    因為研究小組還發現異常豐富、微小的動物住在沉積物裡

  • called loriciferans, and they were seemingly very alive.

    叫做鎧甲動物門,它們似乎還活得好好的。

  • Loriciferans are pretty weird creatures to begin with.

    首先,鎧甲動物門是非常怪異的動物。

  • Their heads are covered in spines, and their bodies are typically encased in a vase-like shell called a lorica.

    它們的頭上長滿了棘,身體通常被種皮包覆著,其為花瓶狀的外殼。

  • But finding them in an oxygen-free basin was a whole new level of weird.

    但是在無氧盆地中找到它們,卻是全新奇異的層次。

  • The researchers observed that the loriciferans were still taking up nutrients,

    研究員觀察到,鎧甲動物門仍在吸收營養,

  • and that some had recently molted.

    有的最近還脫皮。

  • Some even had developing offspring inside them.

    有的甚至在體內生出後代。

  • So these animals apparently spend their lives buried in this sediment, with no oxygen,

    因此,這些動物明顯是在沒有氧氣的情況下,埋葬在這種沉積物中,

  • not only surviving, but thriving.

    不只活著而已,還茁壯成長。

  • Part of this incredible survival might be down to their size.

    這種難以置信的生存,部分原因是其大小的關係。

  • At less than one millimeter long, loriciferans have pretty low energy needs.

    鎧甲動物門長不到一毫米,它們對能量的需求也很低。

  • But they also seem to have some unique adaptations.

    但它們似乎也有些獨特的適應力。

  • For one thing, they don't have mitochondria!

    一來是,它們沒有粒線體!

  • Instead, they have cellular structures that look a lot like hydrogenosomes.

    取而代之的是,它們的細胞結構看起來很像製造氫氣的粒線體。

  • These are organelles that some microbes use to produce energy,

    這些胞器是某些微生物用來生產能量用的,

  • and they use hydrogen ions in place of oxygen.

    它們用氫離子來代替氧氣。

  • Alongside these structures, the researchers also noticed shapes that might be microbes

    除了這些結構外,研究人員還注意到,外型可能是微生物

  • living inside the loriciferans' cells.

    住在鎧甲動物門細胞內的原因。

  • That's intriguing because some anaerobic, single-celled organisms also have symbiotic microbes

    這很有趣,因為某些厭氧的單細胞生物

  • that live alongside their hydrogenosomes.

    也有一起住在粒線體的共生微生物。

  • All in all, it looks like these loriciferans have developed similar cellular structures

    總之,這些鎧甲動物門為了以同樣的方式生存,

  • to anaerobic microbes for living in the same way,

    似乎發展出與厭氧微生物相似的細胞結構,

  • although it's not clear how they did this.

    但還不清楚它們是如何做到。

  • One option is that they retained these adaptations from an earlier ancestor

    一種說法是,它們保留古早祖先的這些適應性,

  • more similar to anaerobic microbes.

    與厭氧微生物更相似。

  • But it's also possible that their ancestors swiped genes from their microbial neighbors,

    但是,它們的祖先也可能是偷走微生物鄰居的基因,

  • allowing them to use the same cellular tricks for survival.

    讓它們使用相同的細胞技巧來生存。

  • Of course, this is an extraordinary claim, and some researchers have doubts.

    當然,這是很特別的說法,有些研究人員仍有疑問。

  • For example, a study published in 2015 looked in the same basin

    例如,2015 年發表的一項研究也在同一個盆地進行,

  • and was unable to find independent evidence of living loriciferans.

    卻無法找到鎧甲動物門活著的獨立證據。

  • The researchers of the original study are still confident in their results,

    最初研究的研究人員仍對他們的結果有信心,

  • but it may take more confirmation to convince everyone.

    但可能還需要更多佐證才能使人信服。

  • If these results do hold up, though,

    如果這些結果真的成立,

  • it could change how we understand the requirements of complex life.

    那可能會改變我們對複雜生命的理解。

  • It would have implications for the diversity of animal life in the world today,

    這會對現今動物生命的多樣性產生影響,

  • for scientists interested in how life got started on an oxygen-deficient early Earth,

    對於生命如何在缺氧的地球上孕育所感興趣的科學家,

  • and maybe even for scientists looking for life elsewhere in the solar system.

    甚至對於在太陽系其他地方尋找生命的科學家來說也一樣。

  • Ultimately, life is so adaptable and endlessly diverse,

    最後,生命的適應力很強,還有無限的多樣性,

  • that we wouldn't be shocked if there are more surprises to be found.

    如果發現更多驚喜,也嚇不著我們。

  • Critical thinking in science is obviously a great thing, though,

    科學中的批判性思考顯然是件好事,

  • and that's why it's so important for researchers to check each other's work.

    研究人員為何會確認彼此間的工作,也是如此重要的原因。

  • And if you want to brush up on your critical thinking skills, or just learn some really cool stuff,

    如果你想提高自己批判性思考的能力,或是想學一些很酷的東西,

  • the Daily Challenges from Brilliant are a great way to do that.

    Brilliant 的每日挑戰是個很棒的選擇。

  • Every day, Brilliant has new challenge questions about math and science topics.

    Brilliant 每天都有新的挑戰問題,主題是數學和科學。

  • They're short, fun, and you can access them every day of the week for free!

    它們簡短有趣,你每天都可以免費使用!

  • Like, I just completed one about black body radiation in a real life setting: a campfire!

    像我才剛完成現實的黑體輻射:營火!

  • If you become a Premium member, you'll also get access to the whole archive of questions.

    如果你成為高級會員,你也可以獲得整個問題的檔案。

  • Best of all, the first 200 people to sign up at Brilliant.org/SciShow,

    最棒的是,前 200 名到 Brilliant.org/SciShow 註冊

  • will get 20% off an annual Premium subscription.

    可以獲得年度高級訂閱的 8 折優惠。

  • And if you check it out, well, hey, thanks for supporting us!

    如果你註冊了,嘿,感謝支持我們!

This week of SciShow is supported by Brilliant!

本週的 SciShow 是由 Brilliant 贊助!

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B1 中級 中文 美國腔 動物 氧氣 粒線體 微生物 細胞 研究

這些動物不需要氧氣? (These Animals Don't Need Oxygen?!)

  • 74 4
    Jerry Liu 發佈於 2021 年 01 月 14 日
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