The rare footage was taken when filming the red crab migration on Christmas Island.

Octopuses edit their RNA to adapt to fluctuating temperatures, from the warm waters of summer to chilly ocean temperatures in winter.

Crabby bodies are so evolutionarily favorable, they've evolved at least five different times. So why does this process, known as carcinization, keep happening?

The male octopus was repeatedly filmed violently jolting awake from sleep and engaging in unusual activities, but exactly what prompted this odd behavior is unclear.

By surgically attaching electrodes to octopuses, researchers have been able to peer inside the cephalopods’ minds for the very first time.

Researchers named the newfound species Tripedalia maipoensis, after Mai Po Nature Reserve in Hong Kong, where they discovered the transparent critter.

Octopuses are odd: They have more than one heart and copper-rich blue blood.

Cruise liner guests encountered giant phantom jellyfish off the coast of Antarctica while diving in submersibles, a new study finds.

Sea dragon dads and octopus moms are the extreme marine parents we need, winning photos show.

It seems that the blueprint for complex brain development remains the same, despite 500 million years of divergent evolution.