Octopuses and squids have beaks. The beak is made of keratin - the same material that a bird’s beak, and our fingernails are made of. #FACT
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Orion Magazine - Deep Intellect
Summer of Science - An Octopus That Mates 'Beak-to-Beak'
List of colossal squid specimens and sightings - Wikipedia
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Eight Great Facts about the Common Octopus
collision detection: The Humboldt squid beak: Diamond-sharp
Octopus Facts and Information
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Do Octopus Have Beaks? - OctoNation - The Largest Octopus Fan Club!
Squid: Characteristics, History, Reproduction
The Octopus - Apologetics Press