A monarch butterfly finds the bright flowers of a lantana plant to its liking near downtown Durham. Some butterflies are very specific about where they lay their eggs. Monarchs will lay their eggs only on milkweeds. Milkweeds contain a potent heart poison, which helps to protect them from browsing animals and leaf-eating insects. The monarch is a poisonous butterfly. Animals that eat a monarch get very sick but generally do not die. These animals remember that this brightly colored butterfly made them sick will avoid Monarchs in the future.