Overview
- The study published in PNAS on Oct. 26 recorded Australian jumping spiders overnight and identified a quiescent stage followed by an active REM-like stage marked by eye movements, leg curls and mouthpart twitches.
- Researchers tested responsiveness with acoustic stimuli and found spiders were less likely to wake during both quiescent and REM-like phases, meeting behavioral criteria for true sleep.
- To test sleep regulation the team disturbed spiders at night by releasing live fruit flies and observed an almost 80 percent increase in REM-like behavior during recovery nights, a classic REM rebound.
- Authors interpret the rebound as evidence of homeostatic control of an active sleep stage in an invertebrate, which supports the idea that distinct sleep stages may have deep evolutionary roots.
- The team plans fieldwork in northern Queensland and Western Australia to measure spider sleep under natural light and habitat conditions and to probe how environmental change alters sleep patterns.