Eastern Black Swallowtail - The dark coloration of the female Eastern Black Swallowtail is a form of Batesian mimicry. It mimics the Pipevine Swallowtail (Battus philenor), a toxic butterfly species that birds avoid eating due to the poisonous acids stored from its host plant. By resembling the Pipevine Swallowtail, the palatable Black Swallowtail gets a measure of natural protection from avian predators. (AI Identification - Gemini)