The evolution of wind pollination in angiosperms

Wind pollination (anemophily) of angiosperms probably evolved from insect pollination (entomophily) in response to pollinator limitation and changes in the abiotic environment. Recent evidence suggests that ambophily (a combination of both wind and insect pollination) might be more common than was previously presumed and could represent either a stable or transitional state. We review factors favoring the evolution of wind pollination and analyse the extent of specialization towards such pollination. Phylogenetic analyses suggest that anemophily is more likely to evolve in groups with small, simple flowers and dry pollen. Wind-pollinated plants appear to have a bimodal distribution in selfing rates, but further studies recognizing the possibility of a combination of wind and animal pollination within taxa are needed to clarify this relationship.