Turns out fishes too watch each others` back

Washington DC: Fishes may be better at helping each other out than previously believed as a new study suggests that some of them really do look after their mates.

The ARC Centre of Excellence for Coral Reef Studies at James Cook University study has found that pairs of rabbitfishes will cooperate and support each other while feeding.

While such behaviour has been documented for highly social birds and mammals, it has previously been believed to be impossible for fishes.

Researchers found that rabbitfish pairs coordinate their vigilance activity quite strictly, thereby providing safety for their foraging partner, says researcher Simon Brandl.

"In other words, one partner stays 'on guard' while the other feeds - these fishes literally watcheach others' back," Brandl explained, adding that this behaviour is so far unique among fishes and appears to be based on reciprocal cooperation between pair members.

Reciprocal cooperation, which requires an investment in a partner, which is later reciprocated, is assumed to require complex cognitive and social skills. Skills that fishes have been deemed not to have.

Yet, Brandl says their research shows clear coordination and presents intriguing evidence for reciprocal cooperation between the rabbitfish pairs.

Co-author Bellwood says that the findings should further ignite efforts to understand fishes as highly developed organisms with complex social behaviours.