As most people know jellyfish have no brain but do they know the can still sleep? Well this species of jellyfish called Cassiopeia can!! A team of research at California Institute of Technology discovered that the jellyfish during the night enter a sleep like state where they’re usual rhythmic pulses and movements slow down, the become less aware of surroundings, and react slower to environmental changes. Another cool thing is that if they are disturbed or bothered during this state they become “sleepy” during the day and sometimes enter that sleeping state even when they’re usually active. These Upside Down jellyfish (Cassiopeia) even react to melatonin the same way we do.. by like knocking out.