Earth Touch Wild Oceans has uploaded a new video filmed by Mark Thorpe. The video features a crab using a fire urchin as a shield by carrying the critter on its back. This remarkable symbiosis situation protects the crab from hungry predators while the urchin gets a ride to a free meal.

“This might look like an underwater hostage situation but it’s actually a perfect example of symbiosis. The carrier crab uses the sea urchin as a spiny shield, protecting it from any predators looking for a crabby treat. In return, the sea urchin gets a free ride to new feeding grounds.”

Find the full video here.