Are butterflies poisonous?
Some butterflies such as the Monarch and Pipevine Swallowtail eat poisonous plants as caterpillars and are poisonous themselves as adult butterflies. Birds learn not to eat them. Other good-tasting butterflies (called "mimics") come to resemble them and thus benefit from this "umbrella" of protection.
Pipevine Swallowtail (Battus philenor)