The Goliath birdwing butterfly is one of the largest butterflies in the world, second only to the Queen Alexandra's birdwing. The Goliath birdwing (Ornithoptera goliath) can be identified by its black, yellow and green wings. The name "birdwing" relates to the butterfly's large wings measuring up to 11 inches in diameter and the birdlike style in which it flies.The Goliath birdwing can be found in the tropical rainforests of Papua New Guinea, and fascinatingly enough, it relies on its diet as a form of protection against predators.
Like all butterflies Goliath birdwings do not have mouths, instead they have what is called a proboscis, a long thin tube connected to the front of their head which uncurls itself to allow the butterfly to drink. Butterflies also only have taste buds on their feet. Caterpillars on the other hand do have mouths and so they are able to eat the leaves of plants.
When Goliath birdwing caterpillars first hatch, they first consume the egg from which they hatched. From then onward, the furry caterpillars feed on rare poisonous vines, including several species of Aristolochia which can only be found in the depths of the rainforest of certain countries such as Papua New Guinea.
Caterpillars feed on toxic vines in order to protect themselves against predators such as birds and reptiles. Goliath caterpillars themselves aren't harmed by the plant, but they become toxic to other animals, so that any animal which eats the Goliath will become extremely sick, although it won't die. The toxicity is enough to deter the animal from feeding on Goliaths in the future. This survival technique means that one butterfly is sacrificed to save others of the same species in the future.
Adult Goliath birdwings can be found fluttering around the canopy area of the rainforest. They survive on a diet of nectar which they extract from a range of flowers growing many meters above ground. They do this using their proboscis. Although their diet no longer consists of poisonous vines after the caterpillar stage, the butterfly continues to be poisonous for predators.
Although adult Goliath birdwing's no longer feed on the vines of the Aristolochia, the butterflies still depend heavily on the plant as a place to lay their eggs and for their larvae to feed on. In recent times, several species of the Aristolochia have suffered as a consequence of land clearing for urban development and farming. As the food source drops in numbers, so do the Goliath birdwing butterflies.