A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Termites work 24 hours per day and they do not sleep.
57
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
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
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
Honeybees never sleep.
276