A new scientific study suggests that some spiders enter a state of sleep similar to humans
A new scientific study suggests that some spiders are capable of a state similar to a human’s REM sleep, which allows us to dream.
REM sleep, as the name suggests, occurs in creatures that can move their eyes. The signs have been noted in mammals and many species of birds, but never before in an insect or arthropod.
The jumping spiders observed in the new study have movable retinal tubes that direct their gaze in this way.
“We report evidence for a state of REM sleep in a terrestrial invertebrate: periodic episodes of retinal movements associated with limb twitching and stereotypical leg-rolling behaviors during nocturnal rest in a jumping spider.” noted the authors in the abstract of the study in the journal Proceedings. of the National Academy of Sciences (PNAS).
In other words, spiders toss and turn and avert their blind gaze, just like humans do during their dreams.
That said, the study scientists weren’t sure if the rest period at night actually counted as sleep, according to the Associated Press.
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Other scientists have also expressed skepticism about the idea that spiders sleep.
“There can be animals that have activity in calm states. But are they in REM sleep? It’s hard to imagine they could be the same thing,” Jerry Siegel, a researcher at the UCLA Center for Sleep Research, told the AP.
The question of whether the dream of jumping spiders also remains scientifically unanswered.
“I think they are dreaming. But scientifically proving that is going to be another story,” study co-author Daniela Roessler told The Wall Street Journal.
The similarity between the spider’s resting state and human REM offers further avenues of exploration, including learning more about when creatures first developed the ability to REM.
“If spiders have REM sleep, that changes the landscape of REM evolution,” said Paul Shaw, a professor of neuroscience at Washington University in St. Louis who was not involved in the study. at the Wall Street Journal.