Scientists have found that some fish are able to move swarms in total darkness. Do not lose sight of each other luminous signals.
Usually schools of fish move exclusively during the day, because individuals must see each other to coordinate direction movement. In low light flocks break up. But Researchers found that phono-eyes stick together without Sveta. They are capable of bioluminescence – glow in the dark. More precisely, this ability is given to phono-eyes by symbiont bacteria, living on the head of fish.
The study involved a large phonoreye (Anomalops katoptron), although other species are also capable of bioluminescence Phonoreglazid family (Anomalopidae)
At night, animals swim using a kind of navigation lights – bioluminescent flashes. Moreover, only some members of the pack, while others only focus on them when choosing a direction.