Clever Trout Match Chimps in a Cognitive Challenge

Certain forms of collaboration are supposed to be so sophisticated that only the smartest creatures—namely humans and perhaps a few close relatives—are capable of them. As demonstrated in a series of experiments published today in Current Biology, coral trout not only solicit the help of moray eels when they hunt, but also pick their hunting partners wisely. "Prior to our study, chimpanzees and humans were the only species known to possess both of these abilities," said zoologist Alex Vail of England's University of Cambridge. In earlier research, Vail and colleagues observed that coral groupers and coral trout—two closely-related species of large, reef-dwelling predatory fish found in the Indian and western Pacific oceans—used their bodies to point moray eels at prey hiding in otherwise inaccessible seabed holes. In the new study, Vail and his colleagues, fellow Cambridge zoologist Andrea Manica and biologist Redouan Bshary of Switzerland's University of Neuchatel, decided to give coral trout an especially challenging test, adapting an experiment originally conducted with chimpanzees.