title: Phenological adaptations in Ficus tikoua exhibit convergence with unrelated extra-tropical fig trees.
abstract: Flowering phenology is central to the ecology and evolution of most flowering plants. In highly-specific nursery pollination systems, such as that involving fig trees (Ficus species) and fig wasps (Agaonidae), any mismatch in timing has serious consequences because the plants must balance seed production with maintenance of their pollinator populations. Most fig trees are found in tropical or subtropical habitats, but the dioecious Chinese Ficus tikoua has a more northerly distribution. We monitored how its fruiting phenology has adapted in response to a highly seasonal environment. Male trees (where fig wasps reproduce) had one to three crops annually, whereas many seed-producing female trees produced only one fig crop. The timing of release of Ceratosolen fig wasps from male figs in late May and June was synchronized with the presence of receptive figs on female trees, at a time when there were few receptive figs on male trees, thereby ensuring seed set while allowing remnant pollinator populations to persist. F. tikoua phenology has converged with those of other (unrelated) northern Ficus species, but there are differences. Unlike F. carica in Europe, all F. tikoua male figs contain male flowers, and unlike F. pumila in China, but like F. carica, it is the second annual generation of adult wasps that pollinate female figs. The phenologies of all three temperate fig trees generate annual bottlenecks in the size of pollinator populations and for female F. tikoua also a shortage of fig wasps that results in many figs failing to be pollinated.
authors.affiliation: Ecological Security and Protection Key laboratory of Sichuan Province, College of Life Science and Biotechnology, Mianyang Normal University, Mianyang, Sichuan 621000, China.
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Zhao
authors.affiliation: School of Biology, University of Leeds, Leeds LS2 9JT, United Kingdom; Department of Zoology and Entomology, Rhodes University, Grahamstown 6140, South Africa.
authors.forename: Stephen G
authors.initials: SG
authors.lastname: Compton
authors.affiliation: Ecological Security and Protection Key laboratory of Sichuan Province, College of Life Science and Biotechnology, Mianyang Normal University, Mianyang, Sichuan 621000, China.
authors.forename: Yong-Jiang
authors.initials: YJ
authors.lastname: Yang
authors.affiliation: School of Biology, University of Leeds, Leeds LS2 9JT, United Kingdom.
authors.forename: Rong
authors.initials: R
authors.lastname: Wang
authors.affiliation: Ecological Security and Protection Key laboratory of Sichuan Province, College of Life Science and Biotechnology, Mianyang Normal University, Mianyang, Sichuan 621000, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000818:Animals; D002681:China; D030681:Ficus / Q000254:growth & development* / Q000502:physiology; D005638:Fruit / Q000254:growth & development* / Q000502:physiology; D054817:Pollination; D012621:Seasons; D014863:Wasps / Q000502:physiology