Among the adaptations of a giant squid are a complex brain, advanced nervous system and the largest eyes of any animal. Its two long tentacles lined with teethed suction cups allow it to grasp prey. It draws water into its mantle and forces it out the back as a propulsion system. Its ability to squirt dark ink helps to foil predators.
Scientists speculate that the giant squid's large eyes enable it to detect bioluminescent light and tones of light in deep water. It is also able to detect such predators as the sperm whale from a distance. Giant squid feed on deep-sea fish, crustaceans and other squid. After capturing its prey with its tentacles, it brings the prey to its strong beak. Its tongue, which has teeth, rips it apart before it goes on to the esophagus.
The squid's propulsion system is aided by fins on the sides of the mantle, which it uses as rudders.
Though giant squid inhabit all the world's oceans, much is still unknown about their habits and range due to their deep-sea habitat. All scientists previously knew about the creatures was what they could learn from specimens brought in by fishermen or washed up on beaches. However, in 2004 Japanese scientists photographed the first images of a live giant squid. In 2006 an 11-foot-long female giant squid was brought in live by a team from the National Science Museum of Japan, but it died in the process of capture. In 2012 the Discovery Channel released the first video footage of a giant squid in its natural habitat.