Weird and wonderful members of the plant kingdom - carrion plants

Unlike the fragrant blossoms that attract bees, butterflies and moths, carrion flowers simulate the odour of a rotting carcass and attract carrion beetles and a variety of flies including blowflies, flesh flies and midges. Not only do these flowers smell like a dead animal, but their petals are typically flesh-coloured, often with a dense covering of hair and unusual shapes, often rather phallic! Certain orchids bear spotty patterns that resemble clusters of flies already enjoying a meal, and movable parts in the flower that catapult a visiting fly into a position of contact with the pollen masses or receptive stigma. Although not true carrion flowers, there are many other species with bad-smelling flowers that attract flies, including a number of orchids and the male flowers of carob trees. While humans have an innate advantage in associating foul-smelling food with illness and disease-causing microbes - because it stops them eating stuff that could kill them, blowflies perceive these same stenches as a potential meal for themselves and their ravenous maggot offspring. Carrion insects feed on pooh, rotting flesh and other decaying organic matter, and lay their eggs in these damp, putrid-smelling places to give them an easy first meal. Carrion flowers lure these insects into their blossoms - while the flowers get pollinated, the outcome for the insects is pretty miserable, when their maggots hatch, they die, because there isn't any suitable food - unlike most insect-pollinated flowers, these carrion flowers do not generally waste energy by rewarding their pollinators with nectar.

In some carrion flowers the insects are lured into dark openings leading to the putrefying interior where they become trapped among the floral organs. This strategy insures cross pollination, especially when the male anthers release pollen several days after the female stigma is no longer receptive. When the imprisoned insects are allowed to leave they are given a thorough dusting of fresh pollen to be taken to a different plant. The European Dutchman's pipe has unusual blossoms with a shape like a pitcher plant that give off a foul and extremely pungent odour. Small gnats land on the vertical upper calyx surface but slip down through the floral tube and into the inflated 'pipe chamber' because the inner surface is line with slippery wax granules - rather like us trying to walk on a floor covering in marbles. Then, thickly packed, downward-pointing hairs in the floral tube prevent the gnats climbing up and out. During their incarceration the gnats do receive rations of nectar - to keep them alive. Several days later, when the anthers release pollen, the jail hairs actually wilt and the flower tilts itself to the horizontal, allowing the pollen-laden gnats to walk out of their prison, and into another receptive floral trap on a different plant.

Stinkhorn photograph by Vik Nanda, used under a creative commons attribution licence