Why Chilies Are Hot

摘要

The ingredient that provides the sting in pepper sprays used for self-defense is capsaicin, the same chemical that lends jalapenos, habaneras, 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 suggests that hot peppers crank up the capsaicin content for self-defense too. Joshua Tewksbury, a biologist at the University of Washington in Seattle, analyzed the distribution of different varieties of chili pepper in Bolivia, where chilies are believed to have first evolved. He found that areas with the greatest number of fruit-eating insects had hotter chili peppers than other areas.