Welcome to brain Stuff production of I Heart Radio. Hey brain Stuff. Lauren Vogelbaum here with a classic episode from former host Christian Sagar. In this one, we dip into questions about sleep. We humans sometimes have a strange relationship with sleep, but what about other animals and specifically, what about animals that are very different from us? Is a brain necessary for sleep? Hey brain Stuff, it's Christian Sagar. You probably don't think you have much in common with
a jellyfish. After all, their species don't share elemental properties with you, like you know, a spine or a brain, or even the same interests. The primitive jellyfish in the genus Cassiopeia spends its time resting upside down on the ocean floor, rather than you know, waiting for the next season of Game Thrones. Researchers, though, have now discovered that you and old Cassiopea are more like than anyone might have spected. You both begin and end your days with
a little shut eye. Yes, jellyfish sleep. The study was published online in the September edition of the journal Current Biology. Unlike most jellyfish, Cassiopeia jellyfish often rest on the floor of mangrove swamps and seagrass beds and rarely move from their underwater spots. By lying upside down, the jellyfish exposes the algae on its underside to the sun, allowing it to photosynthesize and live off the food the algae produces.
Ravi Nath, the papers co first author and a graduate student in cal texts Sternberg Laboratory, says that it may not seem surprising that jellyfish sleep, after all, mammals sleep, and other invertebrates such as worms and fruit flies sleep, but Nath points out that jellyfish are the most evolutionary ancient animals known to sleep. This finding opens up many more questions, is sleep the property of neurons? And perhaps
a more far fetched question, do plant sleep? To test whether the jellyfish were actually sleeping, researchers set up cameras and found the jellyfish were largely inactive at night, and they pulsed less during the day about thirty nine times compared to fifty eight times during sunlit hours. Then the team discovered it was harder to rouse the jellyfish at night too. They set up a false bottom within the jellyfish tank and pulled the platform out from under the jellyfish.
When alert during the day, the jellyfish immediately swam to the bottom of the tank. At night, however, it took several seconds for the jellyfish to awake before heading to the tank floor. The researchers also demonstrated that sleep is essential to jellyfish, just like it is to people. After keeping the jellyfish awake during the night with pulses of water, the jellyfish were slosh and sleepy the next day, when they otherwise would have been active. Mondays am i right.
The discovery that jellyfish sleep could be an important next step in sleep research for all types of species. While the basis and function of sleep is still a mystery to scientists, it's often associated with the brain because sleep has a profound impact on memory and learning. Jellyfish don't need a brain to sleep, which could be a revolutionary concept for sleep science. Today's episode was written by Loaurel
Dove and produced by Tristan Neil and Tyler Playing. For more in this and lots of other curious topics, visit how stuff works dot com. Brain Stuff is a production of I Heart Radio or more podcasts in My Heart radio, visit the iHeart Radio app, Apple podcasts, or wherever you listen to your favorite shows.