If you've seen a close-up photo of a spider, you'll know it's cute.
Many fit on the tip of a finger and have large eyes. Daniela Roessler is a behavioral ecologist at the University of Konstanz.
She thinks they are special in a lot of ways. They've been shown to be smart, and they have an incredible vision.
The species of spider's prey is what determines their hunting strategy. They are able to leap great distances relative to their size.
At night, they may dream.
Roessler found that jumping spiders experience rapid eye movement sleep when they sleep.
When our brains show an increase in activity but our bodies remain immobile, REM sleep is the phase of our sleep cycle.
The team filmed jumping spiders and observed their behavior.
The legs would twitch and Curl into the body. When this happened, we'd see that. The eye movements we detected were very obvious.
The study took advantage of the fact that baby jumping spiders have translucent appendages. The team was able to observe the spider's eyes moving through their bodies.
Octopuses have REM-like sleep. Do spiders too? We need to have a closer look at how universal REM sleep and REM-like behaviors might be across the animal kingdom. There are likely many things we can learn from this, since even in humans REM sleep is still a big mystery. 5/7 pic.twitter.com/ZXtlvSUFdj— Dr. Daniela Rößler 🌎 (@RoesslerDaniela) August 8, 2022
Roessler said it's too early to say if the spiders are sleeping. She said they would be testing the behavior to see if it met the definition of sleep.
Mark is a sleep scientist at the University of Iowa.
He said that the behaviors themselves are beautiful. Why do these animals do these things?
In the future, studying these behaviors across the animal kingdom could tell us more about how REM sleep evolved. Almost all mammals and birds have REM-like activity.
Teresa Iglesias is a neuroscience researcher at the Okinawa Institute of Science and Technology. She has studied REM activity in fish.
"I think we're on the verge of finally addressing the questions of: what is REM sleep and what is it for?" she asked. It is possible that sleep and REM sleep evolved once a long time ago and everyone shares the same origin.
It was too early to say if spiders dream. It wouldn't be the same if they did.
She said that it was beautiful to think about the spiders hanging there and trying to catch a fly or mate. It's cute but probably won't be the same.
Roessler pointed out that some spiders have poor vision but are very sensitive to the sound of the waves. She wanted to know if they could dream in vibrations.
Something to think about as we drift off to sleep.