Tuesday, June 30, 2026
Science

Cellular switch casts light on why humans are active in the day

Early mammalian ancestors were nocturnal, sleeping during the day while the dinosaurs dominated the land. However, some mammalian lineages, including human ancestors, independently transitioned to diurnality (active during the day). Scientists have now discovered why humans are not nocturnal. A new...

Cellular switch casts light on why humans are active in the day
Image: Phys.org
Early mammalian ancestors were nocturnal, sleeping during the day while the dinosaurs dominated the land. However, some mammalian lineages, including human ancestors, independently transitioned to diurnality (active during the day). Scientists have now discovered why humans are not nocturnal. A new study published in Science reveals that the answer is in the genes.

Originally published at Phys.org

The Morning Briefing

Subscribe to our Newsletter

Be the first to receive the latest news, market analysis and updates — delivered straight to your inbox.