The animal world is full of fascinating examples of cooperation between different animal species: from cleaner wrasses that rid larger fish of their parasites, or birds from the drongo family that warn meerkats of predators, to octopuses that hunt together with fish. But what mechanisms of perception, learning or decision-making do animals need in order to cooperate with other species for mutual benefit?

To address this question, biologist Eduardo Sampaio from the Cluster of Excellence "Collective Behaviour" at the University of Konstanz (Germany) and the Max Planck Institute for Animal Behavior teamed up with comparative psychologists Alexandra Schnell (Cambridge University; UK) and Piero Amodio (Stazione Zoologica Anton Dohrn; Italy). In their recent article in Current Biology, they explore possible cognitive foundations of cross-species social behaviour using the example of cooperative hunting in octopus and reef fish.

"Partnerships like these challenge traditional views of intelligence and cooperation in the animal kingdom," says Sampaio. "From an evolutionary perspective, social complexity, problem solving and communication do not only arise within one's own group, but can also be shaped by the need to collaborate across species boundaries."