Giant Squid

The giant squid is one of the largest invertebrates in the world, found in the deep ocean at depths of several hundred to over a thousand metres across most of the world's oceans, with confirmed specimens measuring up to around thirteen metres in length, including its two long feeding tentacles. For most of scientific history the species was known almost entirely from carcasses that washed ashore or were recovered from the stomachs of sperm whales, its main natural predator, and it was not filmed alive in its natural deep-sea habitat until 2004, making it one of the last large animals on Earth to be directly observed in the wild. It has the largest eyes of any known animal, thought to be an adaptation for detecting faint light and movement, including the bioluminescent glow of approaching sperm whales, in the near-total darkness of the deep sea. Giant squid hunt fish and other squid using two long tentacles lined with toothed suckers to seize prey and draw it toward eight shorter arms and a sharp, parrot-like beak, and much about the species' behavior, lifespan and full range of size remains poorly understood due to the difficulty of studying it in its natural habitat.