title: Movements of genes between populations: are pollinators more effective at transferring their own or plant genetic markers?
abstract: The transfer of genes between populations is increasingly important in a world where pollinators are declining, plant and animal populations are increasingly fragmented and climate change is forcing shifts in distribution. The distances that pollen can be transported by small insects are impressive, as is the extensive gene flow between their own populations. We compared the relative ease by which small insects introduce genetic markers into their own and host-plant populations. Gene flow via seeds and pollen between populations of an Asian fig species were evaluated using cpDNA and nuclear DNA markers, and between-population gene flow of its pollinator fig wasp was determined using microsatellites. This insect is the tree's only pollinator locally, and only reproduces in its figs. The plant's pollen-to-seed dispersal ratio was 9.183-9.437, smaller than that recorded for other Ficus. The relative effectiveness of the pollinator at introducing markers into its own populations was higher than the rate it introduced markers into the plant's populations (ratio = 14 : 1), but given the demographic differences between plant and pollinator, pollen transfer effectiveness is remarkably high. Resource availability affects the dispersal of fig wasps, and host-plant flowering phenology here and in other plant-pollinator systems may strongly influence relative gene flow rates.
authors.affiliation: School of Ecological and Environmental Sciences, Tiantong National Station of Forest Ecosystem, East China Normal University, Shanghai 200241, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Liu
authors.affiliation: Department of Zoology and Entomology, Rhodes University, Grahamstown 6140, South Africa School of Biology, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: Stephen G
authors.initials: SG
authors.lastname: Compton
authors.affiliation: School of Ecological and Environmental Sciences, Tiantong National Station of Forest Ecosystem, East China Normal University, Shanghai 200241, People's Republic of China.
authors.forename: Fo-En
authors.initials: FE
authors.lastname: Peng
authors.affiliation: School of Ecological and Environmental Sciences, Tiantong National Station of Forest Ecosystem, East China Normal University, Shanghai 200241, People's Republic of China.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.affiliation: School of Ecological and Environmental Sciences, Tiantong National Station of Forest Ecosystem, East China Normal University, Shanghai 200241, People's Republic of China xychen@des.ecnu.edu.cn.
authors.forename: Xiao-Yong
authors.initials: XY
authors.lastname: Chen
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000235:genetics; D018742:DNA, Chloroplast / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics*; D030681:Ficus / Q000235:genetics*; D051456:Gene Flow; D005819:Genetic Markers; D018895:Microsatellite Repeats; D008969:Molecular Sequence Data; D054817:Pollination; D017422:Sequence Analysis, DNA; D014863:Wasps / Q000502:physiology*
chemical_list: D018742:DNA, Chloroplast; D018744:DNA, Plant; D005819:Genetic Markers
keywords: Agaonidae; Ficus; Slatkin's paradox; gene flow; insect dispersal; seed dispersal