Bobbit, the bizarre ocean worm that has razor-sharp jaws but no eyes or brain 

Have you seen the 2021 movie Dune? The sand-based creatures in the movie resemble bobbit worms (Eunice aphroditois) in real life. These sand strikers intrigue us for various reasons, including their remarkable length, powerful scissor-like jaws and ambush-hunting strategy. These 9-feet-long worms prefer gravelly and sandy habitats, deep inside the ocean floors. These worms are found in the Indo-tropic Pacific and subtropical water bodies of Bali, New Guinea, the Philippines, Australia, Fiji and Indonesia. Here are some fascinating facts about them. 

Bobbit worms are 20 million years old  
Bobbit worms are quite old. They are one of the few predatory worm species that have ever been found in fossils. Several of their burrows have been fossilized due to the mucus secretions of the worm and iron deposits. The one found in Taiwan is 20 million years old.  

They cannot see you! 
While bobbit worms have two eyes at the front of their heads, they are essentially blind. Then, how do they sense their prey? The worms primarily detect their prey using their five-hooked antennae. They also have ganglions, a collection of nerve cells in the autonomic nervous system, rather than a sizable quantity of brain matter. 

A unique hunting strategy 
Bobbit worms feed on fish and even octopuses and they pop their mouth out of their burrows at night. They detect their prey with their antennae and strike them with their razor-sharp mouthparts with such speed that the victim is sliced into pieces. Marine biologists speculate that these giant worms paralyse their prey by injecting toxins in them. 

They have jaws wider than the body 
The bobbit worm possesses two sets of flexible jaws that resemble scissors and, when open, reach far beyond the worm's body. It waits for its prey by opening its jaws and protruding them from its burrow. Think how frightening that may be! The broad jaws of the Bobbit worm are surprisingly strong, and its mandibles are powerful enough to slice its victim in two! 

 There are iron deposits around their burrow  
Yes, bobbit worms are known to have iron deposits outside of their burrows. But how does it happen? The answer would be bacteria. Bobbit worms dig an L-shaped tunnel in the sand to conceal themselves. They cover the burrows with mucus as they reach sexual maturity, creating a more durable attachment in the sand. Bobbit worms secrete a lot of nutrients in their mucus, which microorganisms love! The carbon-rich mucus of the Bobbit worm is particularly attractive to sulphate-reducing bacteria. What do the microbes do? They feed on the secretions of Bobbit worms, fostering an environment where sulphate is converted to sulphide. When parts of the burrow are exposed to oxygen present in the ocean’s saltwater, the iron sulphide transforms into iron hydroxides such as hematite, limonite or goethite which are iron ores. This is how bacteria help deposit iron outside of the bobbit worm’s den!