You probably sleep about 8 to 10 hours a night. That’s nothing compared with this species of dormouse. The tiny rodent from Europe can sleep for 346 days straight—that’s more than 11 months! This is the second-longest sleep of any mammal. Scientists in Austria made the discovery.
When there’s a good food supply, adult dormice will hibernate from October to May. But when food is scarce, some adults tuck in early and sleep through the summer. This lets them skip a poor growing season so they can put their energy into raising their young the following year.