The Immense Diversity of Floral Monosymmetry and Asymmetry Across Angiosperms
The Immense Diversity of Floral Monosymmetry and Asymmetry Across Angiosperms
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DOI：
10.1007/s12229-012-9106-3
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发表时间：
2012-12-01
期刊：
影响因子：
4
通讯作者：
Endress, Peter K.
中科院分区：
文献类型：
--
作者：
Endress, Peter K.
花的单对称性和不对称性可以追溯到被子植物的目和科。这两种植物在被子植物中种类繁多，分布广泛。不同形式的单对称和不对称的系统分布表明，两者都进化了无数次。精致的形式出现在高度合生的花中。不太复杂的形式是由于器官的弯曲和器官数量最少的简单性而产生的。精细的不对称形式是从精细的单对称发展而来的。通过器官的弯曲或扭曲，通过花被器官的覆瓦状卷褶，或者也通过简单性，不太精致的形式出现。花的单对称性似乎是某些群体的关键创新（例如，兰科，豆科，唇形科），而不是在其他。花的不对称性是豆科植物的一个重要创新。简单的单对称模式似乎很容易“恢复”为多对称，而复杂的单对称很难在不破坏花功能的情况下失去（例如，兰科）。单对称和不对称可以在花（和果实）发育的不同阶段表达，并且在某些类群中可能是短暂的。这两种对称性在蜜蜂授粉的花中最常见，并且似乎特别容易在一些特殊的生物学情况下发展：单对称性，例如，蜜蜂授粉的花或油花的不对称性，以及蜜蜂授粉的花的不对称性，两者都基于授粉蜜蜂的特定采集机制。花的单对称性已经发展成为进化发育研究中的模型性状，而花的不对称性至今还没有在分子遗传学研究中得到解决。
Floral monosymmetry and asymmetry are traced through the angiosperm orders and families. Both are diverse and widespread in angiosperms. The systematic distribution of the different forms of monosymmetry and asymmetry indicates that both evolved numerous times. Elaborate forms occur in highly synorganized flowers. Less elaborate forms occur by curvature of organs and by simplicity with minimal organ numbers. Elaborate forms of asymmetry evolved from elaborate monosymmetry. Less elaborate form come about by curvature or torsion of organs, by imbricate aestivation of perianth organs, or also by simplicity. Floral monosymmetry appears to be a key innovation in some groups (e.g., Orchidaceae, Fabaceae, Lamiales), but not in others. Floral asymmetry appears as a key innovation in Phaseoleae (Fabaceae). Simple patterns of monosymmetry appear easily "reverted" to polysymmetry, whereas elaborate monosymmetry is difficult to lose without disruption of floral function (e.g., Orchidaceae). Monosymmetry and asymmetry can be expressed at different stages of floral (and fruit) development and may be transient in some taxa. The two symmetries are most common in bee-pollinated flowers, and appear to be especially prone to develop in some specialized biological situations: monosymmetry, e.g., with buzz-pollinated flowers or with oil flowers, and asymmetry also with buzz-pollinated flowers, both based on the particular collection mechanisms by the pollinating bees. Floral monosymmetry has developed into a model trait in evo-devo studies, whereas floral asymmetry to date has not been tackled in molecular genetic studies.