German Study Finds Some Spiders Can 'Sleep'

A new study finds arachnids, specifically jumping spiders, can doze off in a dream-like state with rapid eye movement.

Dr. Daniela Rößler (Roessler) is a behavioral ecologist from Konstanz University in Germany, and author of the study. She said spiders have behaviors which suggest they fall into a form of sleep.

We actually see twitching and uncontrolled leg movements, coupled with actual retinal movements.

"Scientists can't scan a spider's brain, and obviously can't quiz them about their dreams," Rößler said. "So the next big thing is observing them at night."

Using night-vision, researchers observed jumping spiders attach themselves to silk anchors before "falling asleep."

"So I personally do think that they're experiencing visual dreams, but it will be very difficult to prove that scientifically," Rößler said. ""I would imagine they're going to be dreaming about flies, probably."