In 1962, a French geologist descended into a dark underground cave, but when he emerged more than two months later, he had lost track of time and helped reveal the human body's ...

Discover how Michel Siffre's groundbreaking 1962 cave experiment unveiled the mysteries of human circadian rhythms and time perception, impacting space missions and modern biology.
The New York Times

Human Body Is Found to Have Several 'Clocks'

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