The Most Extreme Complex Life in the World

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more. [♩INTRO] The highest permanent human settlement is
a tiny mining village called La Rinconada, in Peru, which is about
5,100 meters above sea level. Considering that some people start to get
altitude sickness at around 2500 meters, that’s pretty intense. Not everything on Earth is as restricted as
we are, though. You might have heard of the hardcore microbes
that can live at super high elevations or the deepest parts of the ocean. But there are surprisingly complex forms of
life that can survive in those places, too. They just need some extreme adaptations to
do it. The most immediate thing you’ll notice at
higher elevations is that it’s way harder to breathe. The higher you go, the less air pressure there
is. Your lungs struggle to take in oxygen, and
you can develop altitude sickness, where the lack of oxygen causes symptoms like
nausea, a rapid heart rate, and in severe cases, swelling
in the brain. Spend enough time up there, though, and your
body will start to adapt by producing more oxygen-carrying red blood
cells. Other complex animals, like mammals and birds, can have pretty similar problems. And yet, yaks regularly hang out at elevations
of 6,100 meters. To cope with that, they’ve evolved larger
chests, lungs, and hearts, as well as thick, shaggy coats to help deal
with the bitter cold. Researchers have also discovered a bunch of
changes to their genetic code that help them survive up there, like by controlling their body’s stress
response when they’re low on oxygen. Birds can go even higher. The bar-headed goose, for example, regularly migrates over the Himalayas at altitudes
up to 7,000 meters. And the highest known vertebrate ever recorded
is Rüppell’s griffon vulture. In 1973, two pilots flying at 11,000 meters, 2,500 meters higher than the top of Mount
Everest, made a sudden and terrifying discovery when
a bird got sucked into the plane’s engine, forcing
an emergency landing. Not a good day for anybody involved… We don’t fully understand how these birds
do it, but both the bar-headed goose and Rüppell’s griffon vulture have genetic
mutations that allow the hemoglobin proteins in their blood to hold onto more
oxygen. Researchers have also found that when they’re
low on oxygen, bar-headed geese can move more air in and
out of their lungs than any other species we’ve ever studied. Any higher and you start to get into the realm
of microbes. Bacteria, for example, have been found at
the tops of storm clouds and up to 15 kilometers above the surface
of the Earth. We don’t yet totally understand how they
survive, either, but it’s not too uncommon to find microbes
in some of the most extreme environments on Earth. It doesn’t take quite as many genetic changes
to adapt when you’re a super tiny simple organism. Funnily enough, the biggest problem for survival
at extreme depths is the same as at extreme heights, at least for mammals. You start running low on oxygen. The deepest a human has ever dived without
taking oxygen with them is about 250 meters, but that’s nothing compared
to some other mammals. Southern elephant seals can dive more than
2400 meters, and in 2014, scientists watched as a Cuvier’s beaked
whale dove 3000 meters below the surface. Since mammals have to breath air, they need special adaptations to dive that
far. For example, some species have more red blood
cells, can slow down their heart rate, or can temporarily shut down non-vital
organs like their kidneys. Some also have extra myoglobin, a protein
that stores oxygen in muscle cells. But these divers are just visitors. There are species of animals that spend their
entire lives in the deep ocean. In 2017, scientists found the deepest known
vertebrate: a pink, wiggly snailfish at over 8,000 meters down in the Mariana Trench, the deepest part of the ocean. The fish doesn’t have that oxygen problem
that whales and seals do, since it gets its oxygen directly from the water. But there is another problem: pressure. Water is heavy, and the deeper you go in the
ocean, the stronger the water pressure becomes. At 8,000 meters, the pressure is like having a cow sitting
on every square centimeter of your body. And not a small cow either… At that point, the pressure is so great it might actually destabilize the proteins
the fish’s body is made of. To compensate, biologists think the fish’s
tissues are full of a compound called trimethylamine N-oxide, or TMAO for short,
which can help stabilize proteins. TMAO is common in fish, and the deeper you
go, the more of it they tend to have. But even with this adaptation, this may be
the deepest fish we’re ever going to see. Researchers have calculated that beyond 8200
meters, fish would need so much TMAO to withstand
the pressure that their cells would be saltier than the
seawater around them. Except then more water would rush into the
cells through osmosis, and then they would explode, and you can see
why that would be a problem. And yet, we can go even deeper. In 2012, James Cameron, yeah, the guy who made Avatar and Titanic, visited the deepest part of the Mariana Trench
in a submersible. And even there, over 10,000 meters below the
surface, he was greeted by relatively complex life: giant, foot-long
crustaceans known as amphipods, sea cucumbers, and weird, gooey, shelled things
called foraminifera. There’s a lot we still don’t know about
the organisms that live in the deepest parts of the ocean. It’s one of the biggest habitats on Earth,
and yet it’s also the hardest to explore. But we do know that life is super adaptable. And with a collection of those amazing adaptations, complex life can exist at some incredible
highs and some very low lows. If you want to learn more about science, and of course you do, because you’re watching
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100 thoughts on “The Most Extreme Complex Life in the World”

  1. Go to to start streaming Underwater Wonders of the National Parks. Use the promo code ‘scishow’ during the sign-up process to get your first 30 days free.

  2. There was that article from a professor from a British university who claimed those microbes from storm clouds came from outer space. It was so ridiculous, and I was surprised his colleagues didn't not publicly object to it. Just like that nonsense article that came out more recently that said it was plausible that cephalopods came from frozen ova floating from an alien world to ours through space. It was published in a peer-reviewed journal with many many authors supporting it.

  3. 4:02 "like having a cow sitting on every square centimetre of your body". If I were 8000m below, I'd be more worried about there being so many cows down there!

  4. James Cameron doesn't do what James Cameron does for James Cameron. James Cameron does what James Cameron does because James Cameron is… James Cameron.

  5. But none of those environments are that extreme. They are only extreme to US! Bear in mind that oxygen is toxic and corrosive. Look what it does to steel. We have adapted to our environment and they have adapted to theirs.

  6. im glad the ocean deeps are hard to explore so those greedy pigs wont be able to build there land grabbing businesses down there

  7. I just got back from Arapaho Basin Colorado (10,700-13,500) for a Bucket list trip of snowboarding in the Rockies . I thought I was gonna Die just walking to the lift in all my gear. XD. I have never worked so hard to risk my life,… Headed back next week. XP


  9. I rarely find sponsors content to be particularly relevant to me, but this made me subscribe to curiosity stream instantly. Goodbye endless searches for New documentaries on YouTube with actual Scientific value. This is gonna be like heaven. Thanks a ton for that sponsor. I feel saved!

  10. Guys I love your show, love love love it, but come on…meters? You have a lot of American viewers. And I suspect you guys are American. How about throwing in the occasional foot.

  11. Aww you didn't mention Loriciferans, some species are the only known Metazoans that survive without oxygen at all!

  12. i dont understand: curiosity stream was checked out, but it buffers a lot. i dont think ill keep it for the entire 30 day free trial

  13. James Cameron, director of Avatar and Titanic… Are you freakin' kiddin' me? People shouldn't mention Avatar or Titanic when talking about James Cameron as a "director of…", he has Aliens and Terminator 2 under his belt, smh.

  14. Thumbs down. If you are going to express distance in meters, you should have a foreign accent. The metric system is a degenerate measurement system full of arbitrary units of little practical use, it blows my mind that it is so popular.

  15. Ru Paul’s Gryphon vulture can go so high because drag queens can perform feats that normal humans can’t

  16. What can be the simplest form of life possible? Have we discovered the plancton, amoeba or bacteria with the shortest, simplest DNA having the minimum necessary instructions to be a living organism?

  17. In my native language, Yak (the animal), "How?" and "Like" (meaning "alike", "similar") are the same word and they all sound "Yak". So there's this joke:
    – Yak yak? (How's Yak?)
    – Yak yak? (How's how? i.e. confirming the question) Yak yak yak… (Yak like Yak…)

  18. We humans can go deeper than 8000km only with the assistance of a submersible. Other wise we can’t do it. So, I’d rephrase that we can go that deep. That is a lie.

  19. I wonder, do fish that live at great depths have the same pressure inside as outside. If they don't, why not? If they do, wouldn't all the pressure everywhere be balanced, and then it doesn't matter what it is. Anyone knows the answer?

  20. would have been nice if he also talked about incredibly hot, cold and acidic environments but the video was alright.

  21. This was so confusing, why not simplify the measurements? Isn't it much easier to say 5.2 kilometres instead of 52 hundred metres?

  22. There's 2 major things wrong with this video:

    The most complex life at the bottom of the ocean are actually Godzilla and Cloverfield. Don't be so ignorant!

  23. Couldn’t the presence of a contractile vacuole in a fish or that worm thing mean they could have high amounts of “tmao” and not have their cells explode from the rushing in of water into their cells from osmosis ??? Someone answer that

  24. your videos are amazing. Thank you for making them. I have been a fan of you and your brother since you guys started…

  25. James Cameron doesn't do what James Cameron does for James Cameron .

    James Cameron does what James Cameron does because James Cameron is James Cameron .

  26. All I know is that Hank resides in the extreme reaches of my heart. He’s a genuine nerd and I can’t get enough of it.

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