Louis J. Sheehan, Esquire . The ingredient that provides the sting in pepper sprays used for self-defense is capsaicin, the same chemical that lends jalapeños, habaneros, and other chili peppers their heat. But some chilies are a lot hotter than others, and some are mild. What makes certain ones so intense? A new study [pdf] suggests that hot peppers crank up the capsaicin content for self-defense too. http://louis4j4sheehan4esquire.wordpress.com

Joshua Tewksbury, a biologist at the