Swallowtail butterfly tiger swallowtail), Y-linkage determines whether the females are either wild-type (yellow and black) or melanic (dark melanin replaces the yellow background). This genetic difference stems from the fact that melanism is controlled by a single gene, which controls the level of dopamine in the organism. The enzyme BAS, which assists dopamine in producing the yellow pigmentation, normally found on the wings' background, is suppressed. Without the pigmentation, the butterfly appears mostly black (the melanic form) and is a Batesian mimic of "Battus philenor", the pipevine swallowtail. There are also "Papilio glaucus" that are not wholly black; several possess an intermediate
Swallowtail butterfly for protection from predators. Swallowtail tribes Zerynthiini (Parnassiinae), Luehdorfiini (Parnassiinae) and Troidini (Papilioninae), almost exclusively use the family Aristolochiaceae as their host plants. For example, the eastern black swallowtail's main host plant in the wild is Queen Anne's lace, but they also eat garden plants in the carrot family, including carrots, parsley, dill, and fennel. Adult swallowtails sip nectar, but also mud and sometimes manure. The detailed descriptions of morphological characteristics of the Papilionidae, as quoted in Bingham (1905) are as follows: Stages of development of a papilionid, the giant swallowtail ("Papilio cresphontes") The key characteristics that differentiate the Papilionidae