Discover strange facts about cephalopods: octopuses, squids, cuttlefish, nautiluses, and the most intelligent invertebrates on Earth, with camouflage, ink...

Blue-ringed octopuses weigh just 28g but carry enough tetrodotoxin to kill 26 humans. Expert guide to one of the deadliest marine animals on Earth.

Coconut octopuses carry coconut shells for shelter and walk bipedally across sandy bottoms. Expert guide to octopus tool use and why it's so remarkable.

Colossal squid weigh 500kg with the largest eyes of any animal. Expert guide to the Antarctic giant that's actually bigger than the famous giant squid.

Cuttlefish change color faster than any animal despite being completely colorblind. Expert guide to how they see and why their chromatophores are unique.

Firefly squid gather in millions each spring in Toyama Bay, producing spectacular blue bioluminescent displays. Expert guide to nature's light show.

Flamboyant cuttlefish walk on the seafloor and flash bright colors as warnings. Expert guide to the only toxic cuttlefish and why they're so unusual.

Giant squid reach 13 meters and have the largest eyes of any animal. Expert guide to the real kraken, why they remained mythical until 2004, and their deep sea life.

The mimic octopus impersonates flounders, sea snakes, lionfish, and more on demand. Expert guide to the most convincing animal mimic ever discovered.

Nautiluses have existed essentially unchanged for 500 million years, predating dinosaurs. Expert guide to the last shelled cephalopods and their ancient lineage.

Expert analysis of octopus cognition covering tool use, maze solving, jar opening, camouflage decisions, distributed nervous systems, memory, play behavior, and documented escape feats from aquariums worldwide.