“Invasive Asian jumping worms got their name because of the way they thrash around,” Mac Callaham, a Forest Service researcher from the US Department of Agriculture, wrote on the website in 2022.

Jumping spiders such as Evarcha arcuata, the species featured in this study, found throughout Eurasia, are the oddballs of the arachnid class in that they’re so visual.

The team filmed jumping spiders overnight and observed behaviors that mirror REM sleep in other species. "All the legs would curl into the body and they would twitch," Roessler said.

Jumping worms look similar to earthworms but can easily be identified because of the way they thrash around. The worms have been detected in Michigan and pose a threat to the ecosystem because of ...