The growth or tuning of plant root toward or away from moisture
<span>As the goby uses the shrimp's burrow for protection from predators, it also acts as "eyes" for the pistol shrimp. During the day, the goby hovers above the burrow, feeding and interacting with other gobies. Meanwhile, the shrimp uses its antennae to stay in constant contact with the goby's tail while searching for food (detritus, tiny crustaceans and worms) and maintaining the burrow opening. If a predatory fish approaches, the goby flicks its tail several times, alerting the shrimp to retreat into the burrow. If the predator comes within striking distance, the goby will dart headfirst into the burrow. During the night, the two simply rest together in the burrow.</span>