Discover strange facts about jellyfish: box jellyfish, lion's mane, immortal jellyfish, sea wasps, and the brainless ancient drifters that sting, glow, and...

The box jellyfish kills faster than any other venomous animal. Expert guide to the deadliest sea creature, its eyes, venom, and why swimmers fear it most.

Turritopsis dohrnii can reverse aging and return to its juvenile form. Expert guide to the only biologically immortal animal known to science and what it means.

Irukandji jellyfish are only 2.5cm but deliver venom causing 'feeling of impending doom.' Expert guide to Australia's tiny deadly jellyfish.

Expert-written guide to jellyfish biology, the immortal Turritopsis dohrnii, lethal box jellyfish venom, giant lion's mane jellyfish, jellyfish blooms, GFP Nobel Prize research, and the growing jellyfish food industry. Covers anatomy, species profiles, ecological impact, and medical applications.

Lion's mane jellyfish have 37-meter tentacles — longer than a blue whale. Expert guide to the largest jellyfish species and its Arctic habitat.

Moon jellyfish are the most common and recognizable jellyfish species, found in all oceans. Expert guide to Aurelia aurita and its four pink rings.

Portuguese man o' war is actually a colony of organisms, not a single animal. Expert guide to the floating siphonophore and its extremely dangerous stings.

Upside-down jellyfish rest on seafloor with tentacles facing sunlight to grow symbiotic algae for food. Expert guide to these unique mangrove jellyfish.

Everything about the box jellyfish: size, habitat, venom, vision, reproduction, first aid, and the strange facts that make Chironex fleckeri the most dangerous marine animal in the world.

Everything about the lion's mane jellyfish: size, habitat, diet, sting, reproduction, Sherlock Holmes fame, and the strange facts that make Cyanea capillata the largest jellyfish and the longest animal on Earth.

Everything about the moon jellyfish: size, habitat, anatomy, filter feeding, reproduction, blooms, and the strange facts that make Aurelia aurita one of the most studied jellyfish on Earth.

Everything about the immortal jellyfish: size, habitat, biology, transdifferentiation, research history, and the strange facts that make Turritopsis dohrnii the only animal known to reverse-age naturally.