Plant Chemical Defenses

Many of the plant compounds that are useful herbal remedies may be produced by the plants as a chemical defense. Some plants produce bitter compounds that are unpleasant for animals to eat. Others produce poisonous and neurotoxic chemicals for example many members of the tomato family have poisonous leaves. Other plants produce milky latex which coagulates in the insect stomach. Still for every plant that evolved a defense there is a an animal that evolved to be able to resist it. The monarch butterfly eats the poison milkweed plant making itself unappetizing to other predators.