Solving the puzzle of mirror-image flowers

Abstract
Enantiostyly is a plant sexual polymorphism in which female sex organs are deflected to the left or right -- resulting in 'mirror-image' flowers -- but, although it occurs in at least a dozen unrelated families of flowering plants, its adaptive significance has been unclear. Here we show that a mendelian locus governs the inheritance of style orientation and that this curious form of sexual asymmetry functions to promote cross-pollination in bee-pollinated plants.