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  • On the Carribean island of Trinidad, there's a huge, oily lake made from millions of tons of asphalt

  • and it contains the remains of lots of unlucky creatures.

  • But it's not just some giant pond of pavement.

  • Or, death.

  • In fact, this pool of oil and dirt has taught us a lot about lifefrom what it might look like elsewhere in the universe to how we can save what we have right here on Earth.

  • Pitch Lake is the largest naturally-occurring asphalt lake on the planet.

  • And I know what you're thinking right now!

  • You're thinkingthere's more than one?!”

  • Well, there isn't a ton of competition for the title.

  • We only know of about a handful of such lakes.

  • Still, they've gained something of a reputation as places of doom and destruction.

  • And for good reason!

  • Instead of water, the liquid in Pitch Lake is mostly oil; what chemists call hydrocarbons.

  • According to one theory, the lake formed when one tectonic plate forced its way under another.

  • That pushed oil deposits upward from the bowels of the Earth.

  • The lighter components of the oil floated to the top and evaporated,

  • leaving behind a heavy slick which mixed with water, mud, and other things in the surrounding environment to form a dark, thick sludge.

  • That sludge also happens to be a balmy 32 to 56 degrees Celsius.

  • And over the millenia, it has served as a kind of natural trap for wildlife.

  • Though a lot of the lake is solid enough to sustain a person's weight, other parts are more like quicksand.

  • And in those spots, unwary animals can get stuck and sinksomething which has happened a lot.

  • Lots of fossils and skeletons and even archaeological artifacts have been removed from the muck in pristine condition,

  • since the sticky goo prevents them from decomposing or being degraded by the elements or scavengers.

  • In fact, such finds are what Pitch Lake's smaller cousinthe La Brea Tar Pits in Californiais famous for.

  • But don't let all that fool you into thinking asphalt lakes are giant pools of death.

  • Even though there's very little water or oxygen in its quotewaters”, Pitch Lake is actually teeming with life.

  • For example, one 2011 study published in the journal Astrobiology found up to ten million organisms can live in a single gram of sludge from Pitch Lake.

  • Though that's about half of what you'd get from, say, a gram of water from one of the Great Lakes in Michigan, it's still a lot of microbes.

  • And we're not talking about just one type of organism, either.

  • Genetic sequencing revealed an incredible diversity of bacteria and other microbes living within the asphalt,

  • and around thirty percent of the species were previously unknown to science!

  • But, that wasn't what excited the team most.

  • See, the reason this study was published in Astrobiology instead of a regular microbial

  • journal is that there are lakes on other worlds which look a heck of a lot like Pitch Lake.

  • Specifically, the ones on Saturn's moon, Titan.

  • Previous studies had already suggested Titan's lakes check many of the boxes for sustaining life,

  • with one main exception: there's not enough water.

  • The lakes are full of hydrocarbons like methane instead, so it was thought that life simply couldn't survive in them.

  • But, very little water and lots of hydrocarbons seem to be no issue for Pitch Lake's microbes.

  • So, their mere existence suggests it's possible there's life on Titan, too.

  • Of course, there is still some liquid water in Pitch Lake, which is warm,

  • and that's not necessarily true of Titan's methane lakes, which are very cold.

  • And there's a big difference between an environment being able to sustain life and having life arise in it.

  • Still, even if Pitch Lake's microbes aren't a preview of life on Titan, they have a lot to offer their fellow Earthlings.

  • They could help us combat infectious diseases, for example.

  • In a 2018 study, researchers were able to isolate cholic acid derivatives from a Pitch Lake bacterium,

  • molecules generally used to prevent other bacteria from growing.

  • So Pitch Lake's microbes could help us develop new antibiotics, which would be very helpful

  • given that lots of nasty things are becoming resistant to the ones we have.

  • And in addition to saving lives, studying the flora of Pitch Lake could help save the environment.

  • A 2014 study published in Science analyzed miniscule water droplets from the oils of Pitch Lake,

  • and concluded that they contain microbes which actively eat the hydrocarbons in their surrounding environment.

  • Other studies examining the soils next to the lake have also found bacteria that dine on these oils.

  • Which is very good, because hydrocarbons are notoriously difficult to break down.

  • Taken together, these results could have implications for cleaning up oil spills, whether they're on land or in water.

  • Scientists could, for example, introduce oil-eating bacteria to an area to remove a spill more efficiently.

  • And they may not even need the bacteria themselves.

  • It might be possible to isolate the enzymes the microbes use to digest hydrocarbons and

  • use those to develop a way of cleaning up oil on a much larger scale.

  • So yeah, even if Pitch Lake doesn't sound to you like an ideal vacation spot, it's

  • a pretty great thing that so many microbes disagree.

  • And by studying the organisms that think a large, hot lake of asphalt is prime real estate,

  • we can learn a lot of useful thingsand maybe even get a glimpse of what awaits us on other worlds.

  • If all this talk about life on places like Titan has you itching to learn more, I have good news for you!

  • Over on our sister channel SciShow Space, we talk a lot about whether there's other life in the universe,

  • where it's most likely to be hiding, and how we'd know.

  • There are even whole episodes on Titan and what it looks like!

  • And just like this channel, every episode is totally free to watchbecause free, educational

  • science videos are what we do here at SciShow.

  • So all you have to do to learn all about this wonderful, weird universe we live in is

  • head over to YouTube.com/SciShowSpace or click the link in the description.

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アスファルトの巨大なプールから生命の秘密を探る。トリニダードのピッチ湖 (Secrets of Life from A Giant Pool of Asphalt | Weird Places: Pitch Lake, Trinidad)

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    林宜悉 に公開 2021 年 01 月 14 日
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