At 6000 meters below sea level, where sunlight dares not reach, a scientific revolution is taking place. Tiny nodules are producing oxygen out of thin air, challenging everything we thought we knew about the origins of life on Earth.
Dark oxygen: when life plays hide and seek with science
Can you imagine the face of Andrew Sweetman, a researcher at the Scottish Association for Marine Science, when his instruments started reporting the presence of oxygen where there shouldn't have been? Before publishing his study in Nature (if you want to delve deeper, I link it here), his reaction was quite eloquent.
When we first got this data, we thought the sensors were faulty because every study ever done in the deep sea has only seen oxygen being consumed rather than produced.
This "dark" oxygen originates from polymetallic nodules ranging from the size of a grain of sand to that of a human hand. They're not just nice to look at (if you're into underwater rocks, I suppose). They are real walking mines of cobalt, copper, lithium and manganese. Big mining companies look at them like a child looks at a chocolate cake. And now, it appears these nodules have an even more valuable hidden talent: producing oxygen away from light. And that's not all.
The geobattery: plan B
Franz Geiger, an electrochemistry expert at Northwestern University, decided to play around with these nodules. And what did he discover? Which produce electricity. Yes, you understood correctly. We have natural batteries at the bottom of the ocean. This discovery could rewrite the history of the origin of life on Earth. Until now, we thought that aerobic life began thanks to the oxygen produced by plants and algae through photosynthesis. But now? Well, now it seems that all this time life also had a plan B.
A biological treasure (that someone would like to plunder)
Unfortunately, where there is treasure, there is always someone who wants to steal it. Mining companies see these nodules as an underwater jackpot. But Geiger warns:
We need to rethink how to extract these materials, so that we don't deplete the oxygen source for deep sea life.
Translation: “Guys, everyone stop. Before destroying the ecosystem to do more car's battery performance, maybe we should think twice.”
Conclusion: when the origin of life surprises you (6000 meters deep)
So, here we are. We just discovered that the origin of life may have been much darker than we thought. Oxygen, the element we consider synonymous with life, is also produced in the depths of the ocean, in the dark, by rocks that look like underwater potatoes.
How little we still know about our planet. The origin of life is a much more complex and fascinating story than expected. And maybe, just maybe, the next big revelation won't come from outer space, but from the depths of our own planet. So, the next time you look at the ocean, remember: down there, in total darkness, life is still playing to surprise us. And he's doing a damn good job.
