Recently, scientists made a discovery that can only be compared to the discovery of a unicorn. For centuries now, empty, long, tubular shells have been found, but scientists had never had a glimpse of the animal that actually inhabited these baseball bat like shells that measured around 3-5 feet in length. That is, until researchers spotted a group of the animals, called shipworms, in documentary footage of a shallow marine bay in the Philippines. These shipworms were buried vertically in the mud, and the scientists suspected that this was the first example of giant shipworms shells with the worms still inside.

After carefully extracting five of these worms from their muddy home, they proceeded to extract the long, black worms from their shells. The average length of these five was 3 feet, about as long as a baseball bat.

This worm earned its reputation of being “a unicorn for marine biologists”, as stated by study co-author Margo Haygood in a narration for a video showing the removal of one of the shipworms from its shell, by evading scientists since the 18th century.

Shipworm seems like an odd name for the worm, but it makes sense when you learn that they earned this name from their wood-eating habits, and are notorious for infesting and eating wooden ships. Records dating back to 412 B.C. describe sailors protecting their ships against an infestation of these worms by coating their ships in various chemicals.

The worms bury themselves in marine mud and they survive through the activity of special bacteria that live in their gills. As the worms filter the water that is full of rotting wood, the bacteria process hydrogen sulfide produced by the decaying wood and plant material, using it as the fuel for a chemical reaction that results in nourishing organic carbon.

It may have taken literal centuries to track these crazy creatures down, but now scientists can finally start to unravel their unusual biology, life cycle, and symbolic relationship with the bacteria that live in their gills and make their food.