Sky islands as foci for divergence of fig trees and their pollinators in southwest China.

The dynamics of populations and their divergence over time have shaped current levels of biodiversity and in the case of the "sky islands" of mountainous southwest (SW) China have resulted in an area of exceptional botanical diversity. Ficus tikoua is a prostrate fig tree subendemic to the area that displays unique intraspecific diversity, producing figs typical of different pollination modes in different parts of its range. By combining climate models, genetic variation in populations of the tree's obligate fig wasp pollinators and distributions of the different plant phenotypes, we examined how this unusual situation may have developed.

Development of 14 polymorphic microsatellite loci for Ficus tikoua (Moraceae).

Premise Of The Study: Polymorphic microsatellite markers were developed to facilitate studies on the fine-scale population genetic structure of Ficus tikoua (Moraceae), a prostrate shrub known to have highly restricted gene flow.

Methods And Results: Microsatellite primers were developed using the biotin-streptavidin capture method and scanned for polymorphism within 76 individuals sampled from three natural F. tikoua populations.

Extremely high proportions of male flowers and geographic variation in floral ratios within male figs of Ficus tikoua despite pollinators displaying active pollen collection.

Most plants are pollinated passively, but active pollination has evolved among insects that depend on ovule fertilization for larval development. Anther-to-ovule ratios (A/O ratios, a coarse indicator of pollen-to-ovule ratios) are strong indicators of pollination mode in fig trees and are consistent within most species. However, unusually high values and high variation of A/O ratios (0.