People who sleep late have more mental stamina and can outperform early risers.
33
The average cat sleeps about 2/3 of the day.
203
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
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
The human brain is more active during sleep than during the day.
28
The higher someone’s I.Q. the more likely they are to be sleep deprived.
29