Orbea carrion flower. Several species of plants have have evolved carrion-smelling flowers to aid pollination by flies. The flies transfer pollen between the flower's reproductive parts (centre). These comprise the stigma and pollinia (pollen grains fused together). In the background, stems (green) carry stunted leaves (the thorn-like protrusions). These adaptations allow this plant, native to southern Africa, to survive in stony, barren and arid regions.