Mystery #4Tier 3deep-sea microbes darkness

How does a whole world of life thrive around deep-sea vents in total darkness?

Kilometres down on the ocean floor, no sunlight has ever reached, and the water is crushing and cold. By every rule you know, it should be a lifeless desert. Instead, around cracks that gush hot water, giant tube worms sway and pale crabs swarm in the pitch dark. How can a whole world of life feast down there without a single ray of sun?

A dense cluster of giant tube worms on the deep sea floor, their deep red plumes emerging from pale tubes. — Photo: Ifremer · CC BY 4.0 · via Wikimedia Commons

Your guess

With no sunlight at all, what could these deep creatures use to make their food?

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