When is an asymmetric plant-pollinator relationship symmetrical?

The Orchidaceae is a highly evolved, pollinator orientated family with some of the most specialized pollination systems. It has been suggested that plant specialization should be considered along with the degree of specialization of the mutualist partners and that both sides of the mutualistic interaction need to be evaluated to gain insights into the response of species to habitat fragmentation. Here we raise the question of reward systems, in particular, species that are pollinated through deception. The model is applied to two specialist plant genera with different means of deception, food and sexual, and compare the levels of decline of the two genera throughout Europe. We show that there is a highly significant difference between Dactylorhiza (food deceptive) and Ophrys (sexually deceptive) in the rate of decline, with Ophrys suffering much stronger decline consistently across Europe.