Michel Siffre, 85, Dies; Descended Into Caves to Study the Human Mind

He was a pioneer in chronobiology, the study of how our bodies understand the passage of time. He was a pioneer in chronobiology, the study of how our bodies understand the passage of time. Siffre, Michel, Deaths (Obituaries), Caves and Caverns, Research, Biorhythms, Sleep, France NYT > Science