Pistol shrimp dig burrows in and around coral reefs. They share these burrows with the goby fish. They both like to look for food outside the burrow entrance. If a predator comes near the burrow, the goby flicks its tail and alerts the shrimp about the predator. Both of them go into the burrow and hide until it is safe to come out. Both animals benefit from the relationship. The goby gets a place to hide in the shrimp's burrow and the shrimp has a free warning alarm from the goby.

Pistol shrimp with Goby
Photo © Alu Hand; ICRIN

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