Goby and shrimp symbiosis

The symbiosis between gobies and blind burrowing shrimp is a well documented phenomena on coral reefs.

The goby, unable to dig relies on the shrimp to dig a burrow for the pair. The blind shrimp, unable to detect predators, relies on the goby to look out for the both of them. When alarmed the goby will wag its tail - enabling the shrimp to disappear down their burrow for protection.