The unusual cephalopod was spotted on a recent underwater research expedition.

The cephalopods use several strategies to manipulate light and produce their colorful patterns.

Videos reveal how a female squid fertilizes her eggs—one at a time and without spilling much stored sperm.

Thanks to the bioluminescent bacteria inhabiting its light organ, the vividly colored southern bobtail squid (Euprymna tasmanica) can glow in the dark. 

The Hawaiian bobtail squid (Euprymna scolopes) is a nocturnal predator with a light organ full of bioluminescent bacteria attached to an ink sac, which the animal uses to control the amount of light it releases.

A round-up of recent discoveries in behavior research

Scientists develop tape coated with cephalopod proteins to reflect infrared light.

A round-up of recent discoveries in behavior research

Polymer changes color and texture in response to remote signals.