via Medical News Today

For centuries, sleeping has been a great mystery. Many myths and speculations about what happens while we sleep and even the very reasons why we do it have been developed throughout history.

Scientists have of course also always been fascinated by this and have tried to explain the events that happen within the body and especially within our brain while we are in that state of rest.

Although many aspects of sleep are still unknown, it was understood until now that the minimum requirement to sleep was to have a developed nervous system, however, recent studies are shaking that idea.

Scientists from Japan and South Korea conducted research on the Hydra, a small animal that has only two layers of cells and that at its full extension measures a just few millimeters and that has a very simple nervous system and does not have a head or brain, however, it sleeps.

Research suggests that molecules in muscles and other tissues may also regulate sleep despite the lack of a brain to control the nervous system and consequently conclude that the nature of sleep is no longer only neurological.

These discoveries broaden the range of reasons and consequences produced by sleep and indicate that its origin is much deeper and older in the history of the beginning of life on our planet than previously thought.

Research suggests that the family in which hydras and jellyfish are found had already developed sleep patterns before being evolutionarily separated from other animals that did eventually get brains. And they even found similarities in the resting process of these animals compared to the rest:

“At least some genes conserved in other animals are involved in sleep regulation in hydra,” said Taichi Itoh, an assistant professor at Kyushu University and a leader of the study.

These results open a huge research door for scientists that could change the way we think about sleep forever.