Some fish, it turns out, are morning people. They swim hard during daylight, sleep mostly at night, and tend to live longer.

A study has found that observing how actively a fish moves in its youth and when it sleeps can help predict whether it will ...

Activity levels and daytime sleepiness can be combined into a ‘behavioural clock’ that predicts whether a fish will have a short life or a long one.

A new study found that subtle differences in an animal’s behavior by midlife can predict how long it is likely to live.

A new study analyzed the sleep patterns of jellyfish and sea anemones and found they share some sleep traits with humans. The research could provide insight into the origins and function of sleep.