Is it true that the Bone-Eating Worm grows root-like structures that burrow straight into the skeleton, secreting acid to dissolve the bone as they go?

Yes — the Bone-Eating Worm grows root-like structures that burrow straight into the skeleton, secreting acid to dissolve the bone as they go.

Is it true that the Bone-Eating Worm is fed from the inside by bacteria living in those roots, which break down the fats and proteins for it?

Yes — the Bone-Eating Worm is fed from the inside by bacteria living in those roots, which break down the fats and proteins for it.

Is it true that the Bone-Eating Worm was known only from females for years, each one carrying dozens of microscopic males inside her body?

Yes — the Bone-Eating Worm was known only from females for years, each one carrying dozens of microscopic males inside her body.

The worm with no mouth or gut that eats whale skeletons

Q: Is it true that the Bone-Eating Worm has no mouth, no stomach and no gut at all?

Yes — the Bone-Eating Worm has no mouth, no stomach and no gut at all.

Q: Is it true that the Bone-Eating Worm moves onto the bones of a sunken whale within months of the carcass hitting the deep seafloor?

Yes — the Bone-Eating Worm moves onto the bones of a sunken whale within months of the carcass hitting the deep seafloor.

The short version

Osedax, the bone-eating worm, colonises whale carcasses on the deep seafloor. It grows roots that bore into bone and secrete acid to dissolve it, while bacteria inside those roots digest the fats and feed the worm from within. For years every specimen found was female, each carrying dozens of microscopic males inside her body.

Why it's so weird

✓The Bone-Eating Worm has no mouth, no stomach and no gut at all.
✓The Bone-Eating Worm moves onto the bones of a sunken whale within months of the carcass hitting the deep seafloor.
✓The Bone-Eating Worm grows root-like structures that burrow straight into the skeleton, secreting acid to dissolve the bone as they go.
✓The Bone-Eating Worm is fed from the inside by bacteria living in those roots, which break down the fats and proteins for it.
✓The Bone-Eating Worm was known only from females for years, each one carrying dozens of microscopic males inside her body.

📏 How big is it, really?

Bone-Eating Worm

5 cm

a 7-year-old

1.2 m

🧒

You could line up about 24 of them along a 7-year-old!

The full story

This worm has no mouth, no stomach, and no gut at all, and it eats whale skeletons. Meet Osedax, the bone-eating worm, first discovered on a dead whale far down on the deep seafloor. When a whale carcass sinks into the deep, these worms colonise the bones within months. They grow root-like structures that burrow directly into the skeleton, secreting acid to dissolve the bone as they go. Since they cannot actually eat, bacteria living inside those roots break down the fats and proteins and feed the worm from within. Stranger still, for a long time every single one found was female, each carrying dozens of microscopic males inside her body, permanently. A whale skeleton can be stripped away in a matter of years. Follow for more weird animal facts.

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“The Bone-Eating Worm has no mouth, no stomach and no gut at all.”

“The Bone-Eating Worm builds an entire decorated gallery out of sticks just to win a mate.”

“The Bone-Eating Worm moves onto the bones of a sunken whale within months of the carcass hitting the deep seafloor.”