Support for the predictions of the pollinator-mediated stabilizing selection hypothesis

作     者：Mark van Kleunen Anna Meier Moritz Saxenhofer Markus Fischer 

作者机构：Institute of Plant SciencesUniversity of BernAltenbergrain 21CH-3013 BernSwitzerland 

出 版 物：《Journal of Plant Ecology》 (植物生态学报（英文版）)

年 卷 期：2008年第1卷第3期

页      面：173-178页

核心收录：

学科分类：0710[理学-生物学] 071001[理学-植物学] 0907[农学-林学] 07[理学] 0713[理学-生态学] 

主　　题：actinomorphy flower size floral symmetry phenotypic variance zygomorphy 

摘      要：Aims Floral traits are frequently used in traditional plant systematics because of their assumed *** potential reason for the apparent constancy of flower size is that effective pollen transfer between flowers depends on the accuracy of the physical fit between the flower and ***,flowers are likely to be under stronger stabilizing selection for uniform size than vegetative plant ***,as predicted by the pollinator-mediated stabilizing selection(PMSS)hypothesis,an accurate fit between flowers and their pollinators is likely to be more important for specialized pollination systems as found in many species with bilaterally symmetric(zygomorphic)flowers than for species with radially symmetric(actinomorphic)*** In a comparative study of 15 zygomorphic and 13 actinomorphic species in Switzerland,we tested whether variation in flower size,among and within individuals,is smaller than variation in leaf size and whether variation in flower size is smaller in zygomorphic compared to actinomorphic *** findings Indeed,variation in leaf length was significantly larger than variation in flower length and ***-individual variation in flower and leaf sizes did not differ significantly between zygomorphic and actinomorphic *** line with the predictions of the PMSS,among-individual variation in flower length and flower width was significantly smaller for zygomorphic species than for actinomorphic species,while the two groups did not differ in leaf length *** suggests that plants with zygomorphic flowers have undergone stronger selection for uniform flowers than plants with actinomorphic *** supports that the relative uniformity of flowers compared to vegetative structures within species,as already observed in traditional plant systematics,is,at least in part,a consequence of the requirement for effective pollination.