COOKIECUTTER SHARK

These fearsome sharks are rarely seen alive, but are mostly known from the circular wounds they leave in their prey (hence their name). They spend their days in the ‘ twilight zone’, 1,000m down, then rise up at night to hunt in shallower waters. The sharks measure about half a metre in length, and latch onto large fish, dolphins and whales, before slicing out a plug of flesh with their razor- sharp teeth. Cookiecutters glow in the dark, which eliminates their shadow in the dim blue light of the twilight zone. A dark band on their skin may fool their victims into thinking they’re smaller prey fish, which lures them within striking distance.