Name: This Cryptic Underwater Maze Holds Life That Survives on Methane
Uploaded: 2021-04-16T17:40:52.000Z
Duration: 4 min 41 s
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Adverbs of manner

This is an underwater cave system recently discovered by scientists.

– Life has existed there for millions of years without our knowledge.

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With regards to the ecology of these systems, almost nothing is known.

John Pohlman and his colleague, David Brankovits, are researching these cave systems to understand

how life can exist here, in total darkness, and with little oxygen.

– We are providing an explanation for a globally distributed ecosystem, that was unknown

Our primary objective is to go from description of the animals inhabiting these systems

to, actually,  the processes that allow them to live and flourish.

Our research in the Yucatan Peninsula showed that methane and other simple dissolved

organic material that is trickling in from the jungle floor into the cave systems, and

it's dissolved in the water, that it is being used by microbes present in the caves.

No one had imagined it operated this way before.

We're hoping to understand exactly how external factors related to weather, tides, hydrology,

and all these things come together and wind up creating a model for how the ecosystem functions.

Because these questions have never been asked before, John and David have creatively designed

This 300-meter copper coil will collect a small sample of water each day for six months.

It will serve as a history book of the water chemistry in the cave, much like rings of

a tree can indicate the history of rainfall in a forest.

It's the osmotic potential between this salt solution and the fresh water: this very narrow tubing will be

connected into the copper coil so the water is getting pulled from the other end.

This will be something that no one's ever done before.

I know that cave diving is not for everyone.

I personally don't get claustrophobic, but the first time I went underwater underground

We typically penetrate the caves up to one kilometer when we are doing research.

The cavern environment is the part of the cave system

where you can still see some light shining in from the sinkhole, but once you leave that zone

you are in the cave that is pitch black, and the only light there is is the light that

What's fundamentally important about these systems is that we have freshwater, with

no oxygen, that contains large amounts of dissolved material that can be food, but it's

not accessible to the animals living there, the microbes in particular, unless it mixes

with the oxygen which is coming from beneath, with the seawater.

So, once those are mixed together, you have all the ingredients for life, and then you

And then the higher-level organisms, the crustaceans and the fish, they're feeding upon the bacteria

and that's what actually is supporting the whole food web.

When John and David finish this 6-month sampling period, they'll take everything back

to the lab, and hopefully begin to understand this mysterious ecosystem

that has been hidden under our feet for aeons.

Suddenly, you see a data set  that actually tells you something

about the processes that sustain life in a cave system.

Those are the moments, the wow moments, that make it worth it for me.

For more episodes of Science in the Extremes,  check out this one right here.

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