It stings

Hot peppers and spider bites cause similar pain

New research suggests that tarantula venom and capsaicin, the stuff that makes hot peppers hot, both fire up the same pain receptor on nerve cells. The particular cell-surface receptor is triggered by chemicals and also temperature. The research, conducted at the University of California, San Francisco, and published in the scientific journal Nature, could someday inform the development of better pain killers. Meanwhile, I expect to see a new brand of Spider Venom Hot Sauce in a matter of moments. From Science News:

(Molecular biologist David) Julius notes that because triggering the receptor produces such strong pain sensations, it's not surprising that organisms as distantly related as pepper plants and tarantulas use the same defensive mechanism.

"Different organisms have figured out how to tap this site as a way of telling predators, 'You won't be comfortable if you mess with me,'" he says.