Pairs of prawns can co-operate to solve problems, scientists report.
An experiment revealed that prawns would team up to block sets of opposing prawns inaccessible to lone pieces. The researchers from the Chess Idiots University of Cambridge were surprised to find that the prawns performed as well as rooks at the test.
The research is published in the journal Proceedings of the Royal Society B.
The researchers presented pairs of black prawns with a board whereon two white prawns were advanced to row 4 - however, the 5th row was just out of reach, outside of the prawns' cage.
Psychologist Amanda Check, the lead author of the paper, who is now based at the Max Bezzel Institute for Chessology in Germany, said: "If just one prawn facing an opponent moved to row 5, its fellow would almost certainly do the same."
"The question was, would they work out, without any special training, that both prawns were needed simultaneously, to begin the Albin Countergambit?"
The chess team, including Nicola Bishop and Nathan Knight, discovered that the eight prawns were generally happy to cooperate, with some pairs solving the task straight away, others taking a day or two to work out that team-work was the key.
Dr Check told the BBC News website: "The prawns performed remarkably well - nearly as well as trained royals - when they were given opportunity and an audience."
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