Cephalopod snoozing is mostly quiet with brief bursts of REM-like activity
Octopuses cycle through two stages of slumber, a new study reports.First comes quiet sleep, and then a shift to a twitchy, active sleep in which vibrant colors flash across the animals’ skin. These details, gleaned from four snoozing cephalopods in a lab in Brazil, may provide clues to a big scientific mystery: Why do animals sleep?
“So far, we have not found a single species that does not sleep,” says Mourrain, who was not involved in the new study.
Cephalopod neuroscientist and diver Sylvia Medeiros caught four wild octopuses, Octopus insularis, and brought them temporarily into a lab at the Brain Institute of the Federal University of Rio Grande do Norte in Natal, Brazil. After tucking the animals away in a quiet area, she began to carefully record their behavior during the day, when octopuses are more likely to rest.