Got Your Back, Jack

Life is hard in the ocean, and survival is even tougher when you’re tiny. But some of the marine world’s smaller inhabitants have figured out that they can double their chances of survival by pairing up and working as a team.

The colourful, characterful goby and his partner the pistol shrimp are just one such example of a successful team. While the shrimp builds and maintains a cosy burrow with its front claws, the goby moves in and lives side-by-side with it in domestic harmony. While the shrimp does the hard work of shovelling sand away from the entrance and keeping the place looking tidy, the goby acts as a “lookout”, hovering over the burrow and keeping a sharp eye out for any threats or predators in the area.

This works well because the shrimp suffers from very poor eyesight and so uses its antennae to stay in constant contact with the goby's tail while searching for food. As soon as danger looms and the goby darts back into the burrow for safety, the shrimp is alerted and follows close behind. Later, when it’s safe to come out again, the goby will gently wiggle its tail to signal the “all-clear” to its short-sighted partner. In return for its guard duties, the goby gets to share the safety of the burrow and is even kept clean by the shrimp, which grooms it.

The pair are completely dependent on each other, as without the watchful protection of the guardian goby, the shrimp will stop burrowing, and without the shelter of the shrimp’s burrow, the goby will be promptly eaten by predators. So it’s just as well that the mutually beneficial partnership works as well as it does.