A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Sleeping on the job is acceptable in Japan. It is viewed as exhaustion from working hard. Some people fake it to look committed to their job.
57
You forget 90% of your dreams.
256
Some people have a "natural alarm clock" allowing them to wake up when they want. This is actually caused by a burst of the stress hormone adrenocorticotropin.
15
Termites work 24 hours per day and they do not sleep.
57
There's a love mattress that is specifically designed for couples who sleep on each other's arms.
12
People who sleep late have more mental stamina and can outperform early risers.
33
Sea otters hold hands while sleeping so they don’t drift away from each other.
104