A butterfly at the Detroit Zoo! This is actually a Blue Morph Butterfly, mating with another. (You can slightly see the other one below it.)
The Peleides Blue Morpho, Common Morpho, or The Emperor (Morpho peleides) is an iridescent tropical butterfly found in Mexico, Central America, northern South America, Paraguay, and Trinidad. Many authorities believe that peleides is a subspecies of Morpho helenor.
The brilliant blue color in the butterfly's wings is caused by the diffraction of the light from millions of tiny scales on its wings. It uses this to frighten away predators, by flashing its wings rapidly. The wingspan of the Blue Morpho butterfly ranges from 7.5–20 cm (3.0–7.9 in). The entire Blue Morpho butterfly lifecycle, from egg to adult is only 115 days.Known larval foodplants are Leguminosae (Arachis hypogaea, Dioclea wilsonii,Inga, spp., Lonchocarpus, Machaerium cobanense, Machaerium salvadorense, Machaerium seemannii, Medicago sativa, Mucuna mutisiana, Pithecellobium Pterocarpus rohrii and Mucuna urens) and Bignoniaceae (Paragonia pyramidata). Morpho peleides drinks the juices from rotting fruits for food. Its favourites in captivity are mango, kiwi, and lychee. Morpho peleides butterflies live in the rainforests of South America, and can be found in Mexico and Central America.
The larvae of Morpho peleides butterflies are occasional cannibals. The caterpillar Blue Morpho butterfly is red-brown with patches of bright green.
The Morpho peleides butterflies stick together in groups to deter their predators, a form of mobbing behavior.(Source.)