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.
 Monarch (Danaus plexippus) |
 Pipevine Swallowtail (Battus philenor) |
 Viceroy (Limenitis archippus), a Monarch mimic |
 Red-spotted Purple (Limenitis arthemis astyanax), a Pipevine Swallowtail mimic |
