Do butterflies sleep? Can they dream like humans? What do you think they would dream about?
Several insect species, including bees, fruit flies and cockroaches, have been demonstrated to sleep, so it’s probably safe to assume that butterflies do, too. How do we know that insects sleep? Butterflies and other insects cannot close their eyes when they sleep, because they do not have eyelids. However, they do enter a typical “sleep posture”. For example, some native bees spend the night on a plant stem, holding on with just their mouthparts. While asleep, their eyes do not respond to moving images the way they would during the day when they are awake.
More importantly, sleep in insects is necessary to “recharge their batteries” just like it is for us. If they are deprived of sleep, they are less alert, and will sleep in late the next time they get the chance. Sleep-deprived insects have memory issues, just like students who have pulled an all-nighter cramming for an exam.
As to whether they dream, and what they dream about, we can only guess. I would like to think that butterflies dream about warm sunny days in fields full of flowers and plants to lay eggs on. I certainly hope they do not have nightmares about entomologists chasing them with a net!
Source: Helfrich-Forster, C. 2018. Sleep in insects. Annual Review of Entomology 63:69–86