Here's how brainless creatures like jellyfish have shown sleep behaviour

The debate and research surrounding sleep goes a long way. To study the sleep behaviour scientists have always experimented with animals to trace the origins of this neurological behaviour. 

From the tiniest animal like the flies to the blue whale, all sleeps. But jellyfish are among those creatures which spearates from those others by approximately 600 million years ago. 

A scientific research recently has proved that even jellyfish displays sleep like behaviour. This has set the course of debate that if an organism as ancient as the jellyfish without a central nervous system can sleep then the roots of this behaviour is more primordial than thought.  

A jellyfish named Cassiopea who are the only members of the family Cassiopeidae was put to observation and showed decreased pulse rate by one third. 

It was noticed that the creature's daytime activity was reduced if it was deprived of sleep the previous night. At the helm of this research is Ravi Nath, a molecular geneticist at the California Institute of Technology (Caltech) in Pasadena. 

The study was first published on September 21 in current Biology. Ravi Nath was made fun off  at conferences by other scientists at the very idea that such an animal could sleep. 

"We went in at night and videotaped them with an iPhone," said Ravi Nath. Ravi Nath along with his colleagues Abrams and Bedbrook are in search of ancient genes that might control sleep and answer the questions pertaining to evolution of sleep.