Evidence shows fish collaboration on hunting prey

Our results emphasise the importance of a more general evolutionary view of cognition - Fish have the ability to communicate with each other while hunting their prey in ways that were previously known only for humans, great apes, and ravens, according to new research. A study led by Alexander Vail, a Gates Cambridge Scholar at the University of Cambridge's Department of Zoology, found that groupers and coral trout perform a pointing signal to indicate the location of hidden prey to cooperative hunting partners including moray eels, octopuses and Napoleon wrasses. Previously it was only known that humans, great apes and ravens were capable of such communication and the signals were taken as further evidence of their complex and comparable cognitive abilities. The researchers, who include Andrea Manica from the University of Cambridge and Redouan Bshary from the University of Neuchâtel, Switzerland, observed dozens of events where groupers and coral trout performed upside-down headstands with concurrent head shakes to indicate the presence and location of particular prey to cooperative partners. The headstand signal fulfil all the criteria for a referential gesture, being directed at a particular object and recipient, they say, and being acted upon by the recipients. The grouper's signalling shows what are considered key hallmarks of being carried out with intent - that is, the fish has a goal in mind and uses communication to try and achieve it - rather than being an inflexible gesture.