Dreaming Spiders

Spiders – they bite! They jump! They…DREAM?

This is Sandra Tsing Loh with the Loh Down on Science.

It’s bedtime and you stare up at your ceiling. A SPIDER! Do you flee? Do you leave it be? Maybe it’s asleep? Say… do spiders… dream?

Daniela Robler and team from Washington University in St. Louis investigated. They wondered if spiders experience REM sleep. That’s a deep sleep state characterized by rapid eye movements. Vertebrates, like humans, exhibit REM sleep. That’s when most of our dreams happen! 

The researchers filmed jumping spiders while they slept, noting leg twitches and eye movements. These are signs of REM sleep, which they tracked with computer software. 


Spiders twitched and curled their legs, typical of a REM-like sleep state. Their REM-like sleep patterns were similar to those in rats and mice! 

Now we know… invertebrates like our eight-legged friends can also have deep REM sleep!
This study reveals new behavioral similarities across different species. 

*Yawn* I’m feeling sleepy… But maybe – just in case of spiders – I’ll keep one eye open tonight! 

Reference: Rößler, D. C., Kim, K., De Agrò, M., Jordan, A., Galizia, C. G., & Shamble, P. S. (2022). Regularly occurring bouts of retinal movements suggest an REM sleep–like state in jumping spiders. Proceedings of the National Academy of Sciences, 119(33), e2204754119.