Zygomorphic flowers have fewer potential pollinator species

Botanists have long identified bilaterally symmetrical (zygomorphic) flowers with more specialized pollination interactions than radially symmetrical (actinomorphic) flowers. Zygomorphic flowers facilitate more precise contact with pollinators, guide pollinator behaviour, and exclude less effective pollinators. However, whether zygomorphic flowers are actually visited by a smaller subset of available pollinator species has not been broadly evaluated. We compiled 53,609 floral visitation records in 159 communities and classified the plants' floral symmetry. Globally and within individual communities, plants with zygomorphic flowers are indeed visited by fewer species. At the same time, zygomorphic flowers share a somewhat larger proportion of their visitor species with other co-occurring plants and have particularly high sharing with co-occurring plants that also have zygomorphic flowers. Visitation sub-networks for zygomorphic species also show differences that may arise from reduced vi..., Floral visitation data are derived from records archived in the Web of Life and Interaction Web DataBase repositories; original source datasets and the repositories where each was obtained are given in `data/references_all.csv`. Time-calibrated phylogeny derived from the \"ALLMB\" supertree created by Smith and Brown (2018). Details of compilation and processing are given in the paper., ,

植物学家长期以来已确认，两侧对称（zygomorphic）花相较于辐射对称（actinomorphic）花，具有更为特化的传粉互作关系。两侧对称花可实现与传粉者的更精准接触，引导传粉者行为，并排除传粉效率较低的访花者。然而，两侧对称花是否真的仅被可用传粉者物种中的较小类群所访问，这一问题尚未得到广泛评估。本研究整合了159个植物群落的53609条花部访花记录，并对供试植物的花部对称性进行了分类。无论是在全球尺度还是单个植物群落内，具两侧对称花的植物确实仅被更少的传粉者物种访问。与此同时，两侧对称花与其他伴生植物共享的访花者物种比例相对更高，且与同样具有两侧对称花的伴生植物之间的访花者共享程度尤为突出。两侧对称物种的访花子网络同样呈现出差异，该差异或源于访花者类群的缩减……花部访花数据源自Web of Life与Interaction Web DataBase数据库的存档记录；原始源数据集及其获取来源均列于`data/references_all.csv`文件中。本研究使用的时间校准系统发育树源自Smith与Brown（2018）构建的"ALLMB"超级树。数据整合与处理的详细流程见本研究论文。