Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology, NTNU, Trondheim, 7491, Norway.
Research Centre for Ecological Change, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland.
New Phytol. 2019 Jan;221(2):1128-1135. doi: 10.1111/nph.15403. Epub 2018 Aug 26.
In the event of a community turnover, population decline, or complete disappearance of pollinators, animal-pollinated plants may respond by adapting to novel pollinators or by changing their mating system. The ability of populations to adapt is determined by their ability to respond to novel selection pressures, i.e. their evolvability. In the short term, evolvability is determined by standing genetic variation in the trait under selection. To evaluate the evolutionary potential of plant reproductive systems, I compiled genetic-variance estimates for a large selection of floral traits mediating shifts in pollination and mating systems. Then, I computed evolvabilities and compared these among trait groups and against the evolvabilities of vegetative traits. Evolvabilities of most floral traits were substantial yet tended to be lower than the median for vegetative traits. Among floral traits, herkogamy (anther-stigma distance), floral-display traits and perhaps floral-volatile concentrations had greater-than-average evolvabilities, while the evolvabilities of pollinator-fit traits were below average. These results suggest that most floral traits have the potential to evolve rapidly in response to novel selection pressures, providing resilience of plant reproductive systems in the event of changing pollinator communities.
在社区更替、人口减少或传粉媒介完全消失的情况下，动物传粉的植物可能会通过适应新的传粉媒介或改变其交配系统来做出反应。种群的适应能力取决于其对新的选择压力的反应能力，即其可进化性。短期内，可进化性由受选择影响的性状的遗传变异决定。为了评估植物繁殖系统的进化潜力，我编译了大量介导传粉和交配系统转变的花部性状的遗传方差估计值。然后，我计算了可进化性，并在性状组之间进行了比较，同时与营养性状的可进化性进行了比较。大多数花部性状的可进化性相当大，但往往低于营养性状的中位数。在花部性状中，雌雄异位（柱头-花药距离）、花展示性状和可能的花挥发物浓度具有高于平均水平的可进化性，而传粉者适应性状的可进化性则低于平均水平。这些结果表明，大多数花部性状都有可能在新的选择压力下迅速进化，从而为植物繁殖系统在传粉媒介群落发生变化时提供恢复力。
