(Airs Sunday, June 28) Underwater cameraman Bob Cranston explores the remarkable world of marine creatures called cephalopods -- squids, cuttlefish, octopi, and nautili.
With its fascinating coloring and delicate curling arms, the blue-ringed octopus may be a beautiful creature, but this small cephalopod is also deadly.
Meet Dr. Mark Norman, one of the world's leading octopus experts, who is also featured in "Encountering Sea Monsters."
Snakes are not the only creatures that use venom. Scorpions, shrews, spiders, insects, salamanders, and even some types of plants also use poisonous venoms.
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