Sleep, it turns out, is not a luxury reserved for animals with big brains and busy calendars. New research shows that ...

Turns out jellyfish and sea anemones – among the ancient creatures with a nervous system instead of a brain – have a very similar sleeping routine to our own. A new study published in Nature ...

Sleep is one of life’s most universal behaviors. Despite its ubiquity, it’s also one of the most mysterious. Humans spend ...

Though jellyfish don't have brains, they react to light and when presented with food, scientists found.

An upside-down jellyfish drifts in a shallow lagoon, rhythmically contracting its translucent bell. By night that beat drops ...