The colossal squid especially is equipped with a fearsome arsenal of weapons, including barbed swivelling hooks.
|Scars on whale believed to have been caused by Giant Squids
And the number of colossal squid beaks found in the stomachs of sperm whales indicate that the latter often win.
Though colossal squid are encountered remarkably rarely by people, they are thought to make up about three-quarters of sperm whales' diet in the Southern Ocean.
Whereas the whales can spot squid using sonar, the squid can deploy nothing except vision - which suggests there would be a powerful evolutionary pressure towards developing effective eyes.
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