No single person “created” sleep. Sleep is a natural biological process that evolved hundreds of millions of years ago and is found in almost all animals with a nervous system.
Biological origin
Sleep appears to be an ancient, conserved behavior that likely arose as brains and nervous systems became more complex in early animals. It serves vital functions such as energy conservation, restoration, and brain maintenance, which is why every studied animal species shows some form of sleep-like state.
History of study
Humans have tried to explain sleep for thousands of years, with early ideas recorded in ancient Greece, where physicians like Alcmaeon and later Aristotle proposed some of the first natural theories of sleep. Modern scientific sleep research began in the 20th century with figures such as Nathaniel Kleitman, often called the “father of sleep research,” who helped establish the first sleep laboratory and described sleep stages including REM sleep with Eugene Aserinsky.
Mythological creators
In mythologies, different cultures personified sleep as a god or spirit rather than a biological process. In ancient Greece, sleep was represented by the god Hypnos, and in Rome by Somnus, both imagined as divine beings who could “bring” sleep to humans. These stories are symbolic explanations and not accounts of an actual creator of sleep.
