Abstract
Human alterations of natural habitats have caused a pollinator decline, and as a result pollination interactions may be at risk. The impact of pollinator loss on plant communities is, among other things, likely to depend on degree of specialization of plant-pollinator interactions. This project will investigate the effect of loss of functional pollinator groups on reproductive success in plant species with specialized and generalized flower morphology. Extinctions of large pollinators will be simulated in a field experiment on two plant species pairs harbouring self-incompatible, co-flowering species with contrasting flower specialization. Reproductive success in terms of seed set and germination ability will be compared between caged individuals and individuals subjected to natural pollination, and differences in degree of response will be compared between species with specialized vs. generalized flowers. Differences in functional pollinator diversity between species with specialized and generalized flowers will be explored, and the classical theory that specialized flowers receive less heterospecific pollen will be tested by monitoring amounts of heterospecific pollen on arriving pollinators and on stigmas. Specialization has been suggested to be an important trait to predict response to ecological disturbances, but more information about the nature of specialization and its consequences is needed.
Sweden