Adaptive Strategy of Co‐Flowering Species Reducing Deleterious Effects of Heterospecific Pollen Transfer

Abstract

Pollinator visiting multiple co-flowering species is not uncommon in natural communities. Pollinator interspecific moves may bring or deliver heterospecific pollen among different plant species. Heterospecific pollen transfer (HPT) is deleterious to both pollen donor and receipt species, suggesting that co-flowering species may have evolved adaptive strategies to reduce the effects of HPT. One would predict that more pollinator interspecific moves result in higher HPT among interacting species given that HPT is mediated by interspecific moves. If there are no interspecific moves, HPT will not occur. However, heterospecific pollen carried by pollinators may not be picked up by stigmas of the next visiting plant species. A quantification of interspecific moves and consequent HPT involving 14 co-flowering species in an alpine meadow in the eastern Himalaya, southwest China, showed that plant species with more outgoing pollinator moves tended to disperse more of their own pollen to others, as expected. Interestingly, plant species which received more pollinator moves from other species received less HP, suggesting that only species with low acceptance of HP were likely to permit frequent pollinator moves. The paradoxical relation between pollinator interspecific moves and HP receipt unveils an adaptive strategy of co-flowering species limiting deleterious effects of HPT. Bumble bee carrying pollen from multiple plant species. Photograph by Shuang-Quan Huang. A colorful meadow in Shangri-La Alpine Botanical Garden, southwest China. Photograph by Shuang-Quan Huang. These photographs illustrate the article “A paradoxical mismatch between interspecific pollinator moves and heterospecific pollen receipt in a natural community” by Qiang Fang and Shuang-Quan Huang, published in Ecology 97:1970–1978, August 2016. http://dx.doi.org/10.1002/ecy.1433