Description:

This photo depicts four native Northeastern swallowtail caterpillars side by side for comparison. A family portrait of evolutionary relatives, if you will. From left to right: the Eastern tiger swallowtail (Papilio glaucus), pipevine swallowtail (Battus philenor), Eastern black swallowtail (Papilio polyxenes), and spicebush swallowtail (Papilio troilus). As they say, a picture is worth a thousand words. Both the Eastern tiger and spicebush swallowtail caterpillars have fake eyespots and are thought to mimic snakes to deter predators. The Eastern black swallowtail caterpillar is thought to have cryptic coloration to help it blend in among its host plant. The pipevine swallowtail (in dark maroon) feeds on the toxic pipevines, which in turn makes it unpalatable to birds- a trait that it carries over into its butterfly life. The amazing thing is that all the adults of these four species participate in a Batesian mimicry complex in which the Eastern tiger, Eastern black, and spicebush swallowtail butterflies can mimic the poisonous pipevine swallowtail to avoid being eaten!