Plants may need to sleep, just like we do
A new study has suggested that sleep may actually be fundamental to all life, not just to animals.
Scientists in the US have discovered the first evidence of sleep occurring in an organism that doesn't even have a brain - a strong indication that plants, too, many need to take a nap now and again.
The creature in question, a type of primitive jellyfish that spends its entire existence floating upside-down on the bottom of the sea while pulsing every now and again, was found to engage in periods of relative inactivity where the number of pulses decreased from 59 to 38 times a minute.
"It may not seem surprising that jellyfish sleep - after all, mammals sleep, and other invertebrates such as worms and fruit flies sleep," said study co-leader Ravi Nath.
"But jellyfish are the most evolutionarily ancient animals known to sleep."
The findings suggest that there is still much to learn about the role of sleep in nature.
"When humans sleep, we are inactive, we often can sleep through noises or other disturbances which we might otherwise react to if we were awake, and we're likely to fall asleep during the day if we don't get enough sleep," said researcher Claire Bedbrook.
"We might seem extremely different from jellyfish, but we both exhibit a similar sleep state