Science

Humans May Be Cathemeral, Not Diurnal

Updated 2026-08-18 11:10 UTC 1 source Neutral

New evidence from hunter-gatherers suggests humans may be cathemeral, with periods of activity throughout the day and night, challenging traditional views on human sleep patterns.

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New Scientist

Did humans evolve to be active throughout the day and night?

Evidence from hunter-gatherers suggests humans aren't diurnal but cathemeral, with bouts of activity at nighttime – a sleep pattern similar to some lemurs

2026-08-18 11:00 UTC