Jellyfish, with no brains, still seem to sleep

ScienceDaily | 9/21/2017 | Staff
morica (Posted by) Level 3
Click For Photo: https://www.sciencedaily.com/images/2017/09/170921141252_1_540x360.jpg

The work was a collaboration between three Caltech laboratories led by: Paul Sternberg, Thomas Hunt Morgan Professor of Biology and Howard Hughes Medical Institute Investigator; Viviana Gradinaru (BS '05), assistant professor of biology and biological engineering, Heritage Medical Research Institute Investigator, and Director of the Center for Molecular and Cellular Neuroscience of the Tianqiao and Chrissy Chen Institute for Neuroscience at Caltech; and Lea Goentoro, assistant professor of biology. The work appears online in the September 21 issue of Current Biology.

"It may not seem surprising that jellyfish sleep -- after all, mammals sleep, and other invertebrates such as worms and fruit flies sleep," says Ravi Nath, the paper's co-first author and a graduate student in the Sternberg laboratory. "But jellyfish are the most evolutionarily 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 plants sleep?"

Order - Sleeping - Organism - Criteria - First

In order to be considered "sleeping," an organism must meet three critical criteria. First, it must demonstrate a period of reduced activity, or quiescence. Second, the organism must exhibit a decreased response to otherwise-arousing stimuli while in the quiescent state. Finally, the organism must show an increased sleep drive when it is deprived of sleep.

"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," says Claire Bedbrook, co-first author and a graduate student in the Gradinaru laboratory. "We might seem extremely different from jellyfish, but we both exhibit a similar sleep state."

Jellyfish

So, how do you prove that a jellyfish is asleep?

First, to demonstrate quiescence, the team set up a system of cameras to monitor the jellyfish around the clock. They...
(Excerpt) Read more at: ScienceDaily
19 other people are viewing this story
Wake Up To Breaking News!
Tagged:
Sign In or Register to comment.