Swim along the edge of a coral reef and you’ll often see schools of sleek, torpedo-shaped fishes gliding through the currents, feeding on tiny plankton from the water column.
For decades, scientists assumed these plankton-feeding fishes – or planktivores – shared specialised traits: forked tails and streamlined body forms for speed, large eyes for spotting small prey, and small extendable jaws for suction-feeding.
