The mostly male theory of flower evolutionary origins: from genes to fossils
The mostly male theory of flower evolutionary origins: from genes to fossils
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DOI：
10.2307/2666635
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发表时间：
2000-04-01
影响因子：
1
通讯作者：
Parker, DS
中科院分区：
文献类型：
--
作者：
Frohlich, MW;Parker, DS
有花植物进化起源的两个最新理论--花植物理论和新假花植物理论--都是基于被子植物的亲缘关系（来自形态学数据），认为买麻藤目是被子植物的现存姐妹或被子植物的并系。买麻藤类在这些理论的同源性评估和进化情景中占有突出地位。最近的几项研究，包括我们的研究，提供了强有力的证据，证明现存的裸子植物是单系的，所以买麻藤目与其他裸子植物的关系最密切，而不是显花植物。这就消除了两种最新理论的基础，留下了早期的理论，这些理论将显花植物与化石“种子蕨类”裸子植物联系起来，成为唯一活跃的竞争者。我们的同源异型基因Floricaula/LEAFY的数据表明，导致开花植物的谱系最初有两个该基因的拷贝，但其中一个拷贝在开花植物中丢失，这表明了一个新的理论：花组织的发育控制更多地来自裸子植物祖先的雄性生殖结构中活跃的系统，而不是来自雌性，胚珠在原始花中异位。这一理论完全基于活植物的数据，但化石组Corystospermales有男性和女性的结构符合这一理论。被子植物可能包括开花植物的祖先。
The two recent theories of flowering plant evolutionary origins-the Anthophyte and Neo-Pseudanthial theories-are based on phylogenies (from morphological data) that show Gnetales as extant sister to angiosperms or as paraphyletic to angiosperms. Gnetales figured prominently in homology assessments and evolutionary scenarios of these theories. Several recent studies, including ours, provide strong evidence that extant gymnosperms are monophyletic, so Gnetales are most closely related to other gymnosperms, not to flowering plants. This removes the basis for both recent theories, leaving earlier theories that relate flowering plants to fossil "seed-fern" gymnosperms as the only active contenders. Our data from the homeotic gene Floricaula/LEAFY imply that the lineage leading to flowering plants originally had two copies of this gene, but that one copy was lost in flowering plants, which suggests a new theory: that developmental control of flower organization derives more from systems active in the male reproductive structures of the gymnosperm ancestor, rather than from the female, with ovules being ectopic in the original flower. This theory was based entirely on data from living plants, but the fossil group Corystospermales has both male and female structures that fit the theory. Corystosperms could include ancestors of the flowering plants.