As part of the Architeuthidae family, giant squid are deep-ocean dwelling animals that can grow to an amazing size – up to a reported 20m in length (though scientific estimates put this at a maximum of 13m).
Stay buoyant due to ammonia present in body
Giant squid (Architeuthis dux) and some other large squid species maintain neutral buoyancy in seawater thanks to the ammonium chloride solution which flows throughout their body and is lighter than seawater.
The giant squid, which like other squid has 8 arms and 2 longer tentacles, is the world's second largest mollusc (after the Colossal Squid). They catch prey, including deep-sea fish and other squid species, using the 2 tentacles, gripping it with serrated sucker rings on the ends. The maximum weight is estimated at 275kg for females and 150kg for males.
Tales and myths surround these creatures
Tales of giant squid have been common among mariners since ancient times, and may have led to the Norwegian legend of the 'kraken', a tentacled sea monster as large as an island capable of engulfing and sinking any ship.