The Aristolochia (also known as Birthwort) is popular for its rapid growth, its heart-shaped leaves and its uncommonly formed, huge brown-white flowers. Next to its size, these gigantic flowers have another special feature: They form to a pitfall trap in the centre of the flower. This bulbous “kettle” narrows to a small pipe. Insects are lured, crawl deep into the pipe and pollinate the flower that way. The hairs within the flower that kept the insect inside die after two days and set the insect free again. Fruits hanging lose on stalks are sometimes developed as well.