A new study has found that jumping spiders can enter a state of REM sleep, similar to that experienced by humans and other mammals.
The researchers plan to continue investigating what benefits entering such a state of immobilized rest might have.
The study’s lead author suggested that spiders may even experience dreams, which is associated with REM sleep.
Jumping spiders may enter a REM sleep state similar to humans, a new study suggests, prompting experts to theorize what they might experience in such a paralyzed state.
In the study published last week in the journal Proceedings of the National Academy of Sciences, lead author Daniela Roessler and her colleagues observed baby jumping spiders, specifically Evarcha arcuata items, overnight stay
Roessler told the Washington Post that she noticed the spiders were “hanging really neatly, extremely exposed, not in a shelter of silk” and were mostly motionless, confusing researchers involved in the study.
“It was just the most unusual thing I’ve ever seen,” Roessler told The Associated Press of the immobilized and largely vulnerable creatures.
The video revealed patterns of behavior in the baby spiders that closely resembled REM (retinal eye movement) sleep: leg twitches and trembling “retinal tubes,” a part of the spider’s eye that allows its eyes to move and was visible through the spider’s translucent exterior. REM sleep has also been linked to dreaming because of the high brain activity seen in humans and other mammals such as cats and dogs.
“These contractions looked so classic and immediately reminded me of a dog dreaming,” Roessler, who is also a behavioral ecologist at the University of Konstanz in Germany, told The Post.
“Whether that means they’re visually experiencing something similar to how we experience visual dreams is a completely different story,” Roessler continued.
Before the study, Roessler told The Post that little was understood about the sleep patterns of spiders — or about REM sleep in mammals, birds or other creatures as a whole — but she and her colleagues plan to test whether sleep REM of Spiders- What the state is actually sleep in scientific terms, and what benefits the creatures could gain from entering such a state.
“It’s more like they get little rest during the day or … whenever they’re active,” Roessler said. “But I don’t think there was such a clear idea whether they actually sleep for any length of time.”
Lisa Taylor, a researcher at the University of Florida who focuses on jumping spider behavior, told The Post that jumping spiders, in particular, are highly complex creatures, both in their sensory functions and their cognitive abilities.
“They’re not little robots that go out and attack anything they see,” Taylor said. “There’s a lot going on in their brains as they make decisions about whether to attack one thing over another.”
“So if something that happens at night plays a role in that it’s particularly interesting,” he added.
One expert is doubtful that it could actually be REM sleep.
“There may be animals that have activity in quiet situations,” Siegel, a researcher at the UCLA Sleep Research Center who was not involved in the study, told the AP. “But is it REM sleep? It’s hard to imagine that it could be the same thing.”
Read the original article on Business Insider