(Inside Science) Several thousand years ago tube worms thrived near hydrothermal vents on three seamounts in the central Arctic. When the vents became inactive, they died. Most of the softer organic tissue disappeared quickly, leaving nothing but hard tubes on top of these underwater mountains on Langseth Ridge north of the Norwegian Svalbard Archipelago. There they sat for centuries a testament to a lost ecosystem. Then, sponges came along and began to clean up some of the last traces of the tube worms' presence.
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