The Common Birdwing is a big butterfly with a wing span of up to 15 cm, with such a big wing span it can fly at great heights and distances to match. From a distance it would appear to fly like a bird where I supposed is where it got its common name.
Belonging to the Papilionidae species, it has a typical fluttering movement with its forewings whilst its hind wings are kept almost stationary common to the species when feeding on flowers, its favorites are the Pagoda Flower (Cleredendron). Very rarely seen in cities, it is basically a jungle butterfly.As with most insects, there is a high likely hood that it will be sighted near its host plant, Aristolochia acuminata and Aristolochia tagala, both are jungle vines where as a caterpillar it was feeding on. This type of vine contains toxin and the birdwing has evolved to use it to its advantage as a defense mechanism, using the toxin present in the vine and storing them in the fleshy orange-red spines on their backs without harmful effects to itself. Bright color markings on the wings and the orange-red spines on the back serves as a warning to predators that they are toxic and distasteful. If by mistake or ignorance it is attacked, the predator will learn not to make the same mistake twice.
From what I have read, the female can locate the correct plants with chemical receptors on her forelegs to differentiate various leaves, giving them the ability to “taste” the leaves with her legs.
With its majestic size and brightly colored wing markings, it is highly sought after by collectors, fortunately it is listed as an endangered butterfly species under CITES - The Convention on International Trade in Endangered Species and are protected in Malaysia.
Meaning, in real life you can most probably buy them from souvenir shops locally but are not allowed to take it out of the country due to the law prohibiting export of endangered species.