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Topic: REM sleep

Two lions asleep with their heads touching at the top and with ears touching in a cute and loving position (Getty Images/Gregory Sweeney)

The mystery of REM sleep

Matthew Rozsa
Depressed woman in bed with hand on forehead (Getty/ Martin Dimitrov)

While you were sleeping

Kamila Kourbanova - Massive Science
Golden Hound and British short-haired cat (Getty Images/iStock)

In defense of siestas

Chris Idzikowski