Rabbitfish pairs were found to coordinate their vigilance activity quite strictly, thereby providing safety for their foraging partner.

Researcher Simon Brandl said, "We found that rabbitfish pairs coordinate their vigilance activity quite strictly, thereby providing safety for their foraging partner. In other words, one partner stays 'on guard' while the other feeds - these fishes literally watch each others' back. This behavior is so far unique among fishes and appears to be based on reciprocal cooperation between pair members."
Brandl further added that their research shows clear coordination and presents intriguing evidence for reciprocal cooperation between the rabbitfish pairs. Co-author Bellwood said, "The findings should further ignite efforts to understand fishes as highly developed organisms with complex social behaviors."
Source-ANI