The claim:
Humans sometimes swallow spiders (as many as eight per year) while we’re sleeping.
The science:
The thought of an eight-legged critter crawling across your pillow, climbing your face and creeping into your mouth while you sleep is the stuff of nightmares. As you ponder that image, consider this: For even one spider to end up in your mouth would require a series of unlikely events. Here’s why:
- Spiders want nothing to do with humans. The notion that a spider would come anywhere near a sleeping, snoring human is antithetical to spider behavior. There are thousands of species of spiders, but only a handful live in human homes. The vast majority of spiders that live indoors are small and relatively harmless, spinning webs. Some, such as wolf spiders, actively hunt insects, including mosquitoes, flies and even small cockroaches.
- Your open, moist mouth isn’t appealing to a spider. Spiders breathe oxygen and would be repelled by your mouth, which to them would seem like “a warm, moist cave that is mostly carbon dioxide and water vapor,” said Floyd Shockley, an entomologist and the collections manager at the Smithsonian National Museum of Natural History. Vibrations from any snoring also would scare them away, he said.
- The odds are against it. Although it’s theoretically possible a spider could accidentally end up in your mouth, it’s highly unlikely.A spider would have to lose its grip while crawling across your bedroom ceiling at the precise moment it is positioned over your face and then fall squarely into your open mouth. “You’ve got a better chance of winning the Powerball than having a spider fall in your mouth while you’re sleeping,” Shockley said.