There are at least 10,000 species of these swimming bristly worms, some of which pop with brilliant colours or light up with a bioluminescent glow. They’ve adapted to every imaginable marine habitat, from deep hydrothermal vents, to crowded coral reefs, to the open ocean

Earth has witnessed five mass extinction events, one of which killed some 96 percent of all marine species. Polychaetes survived.

One polychaete species can survive without oxygen for 96 hours.

The biggest polychaete is ten feet long.