Bone worms are cool, I could learn about them forever. They have an endosymbiotic bacteria in their roots that secrete acid that dissolves the bone to allow the worm to absorb the collagen, which it digests.

https://en.wikipedia.org/wiki/Osedax

And even though a symbiont plays a critical role in its life cycle, the genus Osedax doesn’t appear to be named after Dax from Star Trek DS9 (which was released before the genus Osedax was even discovered and categorized in the early 2000’s), as Osedax is latin for “Bone Eater”.

Polychaetes in general are just so damn cool. That’s the same class that contains the fairly famous Pompeii worm that lives at the deep sea hydrothermal vents.