Can Octopi Have Nightmares?

By: Abby Huang

In Rockefeller University in New York, an octopus named Costello was napping peacefully in his tank. About half an hour later, Costello entered another sleep stage. His body switched between assorted colors and patterns used for camouflage, as commonly observed in other octopi. However, just a minute later, something peculiar occurred.

Costello began a series of strange movements. He started curling his arms over his body while moving around the bottom of the tank. Next, he suddenly spun around multiple times in a movement similar to a cyclone. The cephalopod then filled his tank with ink. As the ink slowly dissipated, Costello was seen attacking a pipe.

Dr. Eric Ramos, a marine scientist from the University of Vermont, said, “ It looked like he was trying to kill it.” He also stated that Costello’s behavior was not typical for other cephalopods. After the incident, Costello resumed his normal activities, such as eating and engaging with his toys.

The researchers at Rockefeller were just as surprised. “We were completely dumbfounded,” said Dr. Marcelo Magnasco, a biophysicist. He and his team shared their explanations in a study uploaded to bioRxiv; the most prominent theory was that Costello was having a nightmare.

Dr. Magnasco personally believes that Costello was having a dream. All his actions could be deciphered as fighting. Other explanations for this behavior could be a seizure or neurological problems from losing parts of two of his arms. Additionally, there were problems with interpreting Costello’s behavior, the main problem being that Costello had stomach parasites during these episodes.

Dr. Michael Kuba, a marine behavior biologist from The University of Naples Federico II in Italy, argued that Costello’s episodes could be a result of the parasites. He suggested that the curling of arms could have been from cramps.

However, Dr. Magnasco is not the first to suggest that octopi can dream. Multiple groups of researchers have speculated on the changing of colors and textures during the active stage of sleep observed in octopi. Some suggested that this activity could be a side effect of dreaming.

Dr. Kuba and his colleague Dr. Tamar Gutnick have begun their own research on octopi brain activity during sleep, opening up a whole new set of possibilities.