A nudibranch showing a closeup of their fleshy, tentacle-like growths, called cerata.

How Sea Slugs Steal the Defenses of Their Prey

Many tentacle-like outgrowths, called cerata (singular: ceras), project off the back of this aeolid nudibranch. After the nudibranch eats the tentacles of a jellyfish, anemone, coral, or other stinging animal, the stolen stinging cells...
A reddish-orange nudibranch.

A Collage of Nudibranch Colors

Nudibranchs are a kind of sea slug, and their 3000 species are found from the poles to the tropics in both shallow and deep water. Though they often only reach two centimeters in length,...
Juvenile plane-head filefish

A World Adrift: Life in the Sargassum

The open ocean is surprisingly barren to the naked eye. Every now and again you will encounter a school of fish and their attendant predators, but most of the life that you find is...