title: Pollinator sharing and gene flow among closely related sympatric dioecious fig taxa.
abstract: Hybridization and insect pollination are widely believed to increase rates of plant diversification. The extreme diversity of figs (Ficus) and their obligate pollinators, fig wasps (Agaonidae), provides an opportunity to examine the possible role of pollinator-mediated hybridization in plant diversification. Increasing evidence suggests that pollinator sharing and hybridization occurs among fig taxa, despite relatively strict coevolution with the pollinating wasp. Using five sympatric dioecious fig taxa and their pollinators, we examine the degree of pollinator sharing and inter-taxa gene flow. We experimentally test pollinator preference for floral volatiles, the main host recognition signal, from different figs. All five fig taxa shared pollinators with other taxa, and gene flow occurred between fig taxa within and between sections. Floral volatiles of each taxon attracted more than one pollinator species. Floral volatiles were more similar between closely related figs, which experienced higher levels of pollinator sharing and inter-taxa gene flow. This study demonstrates that pollinator sharing and inter-taxa gene flow occurs among closely related sympatric dioecious fig taxa and that pollinators choose the floral volatiles of multiple fig taxa. The implications of pollinator sharing and inter-taxa gene flow on diversification, occurring even in this highly specialized obligate pollination system, require further study.
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, People's Republic of China Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming 650204, People's Republic of China.
authors.forename: Gang
authors.identifier: 0000-0003-1834-9561
authors.initials: G
authors.lastname: Wang
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, People's Republic of China Center for Tree Science, The Morton Arboretum, Lisle, IL 60532, USA.
authors.forename: Charles H
authors.initials: CH
authors.lastname: Cannon
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, People's Republic of China cj@xtbg.org.cn.
authors.forename: Jin
authors.identifier: 0000-0002-9490-9981
authors.initials: J
authors.lastname: Chen
mesh_terms: D000818:Animals; D030681:Ficus / Q000235:genetics* / Q000378:metabolism; D051456:Gene Flow; D006824:Hybridization, Genetic; D054817:Pollination; D013559:Symbiosis; D061350:Sympatry; D055549:Volatile Organic Compounds / Q000378:metabolism*; D014863:Wasps / Q000502:physiology*
chemical_list: D055549:Volatile Organic Compounds
keywords: Ficus; coevolution; floral volatiles; inter-taxa gene flow; obligate pollination; pollinator sharing