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Deep Time - 40 Days of Darkness

July 4, 2025

14 volunteers live underground for 40 days. With no way to mark time, this is an extreme experiment. How do people adapt to these conditions? How do the body and brain react to the loss of a sense of time?

https://p.dw.com/p/4w7zK
Deep Time - 40 Days of Darkness
Image: ZED

A scientific adventure aims to find out.

Deep Time - 40 Days of Darkness
Christian ClotImage: ZED

One day in March, seven women and seven men, led by explorer and researcher Christian Clot, enter the Lombrives cave in the French Pyrenees. They intend to spend 40 days there, without daylight - and with no other means of marking time. 

Deep Time - 40 Days of Darkness
Image: ZED

They begin the "Deep Time” experiment. It is a group experience with an interdisciplinary scientific approach that goes far beyond mere : The aim is to explore people's ability to adapt to extreme situations.

Deep Time - 40 Days of Darkness
Image: ZED

The participants set up their base camp deep in the cave. They have to organize life in the camp and learn to function as a group under extreme conditions. The lack of daylight, cold and fatigue affect the rhythm of each individual in different ways

Deep Time - 40 Days of Darkness
Image: ZED

The deeptimers are equipped with sensors and high-tech devices to collect scientific data -- before, during and after their stay in the cave.

Deep Time - 40 Days of Darkness
Image: ZED

This data is analyzed by experts in the fields of cognitive science, chronobiology, sociology, physiology, psychology, ethnology, social organization and genetics.

Deep Time - 40 Days of Darkness
Image: ZED

The scientists report on their initial findings a few months after the end of the experiment. In the long term, their interdisciplinary analyses will contribute to a better understanding of the mechanisms and limits of human adaptation. 

 

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