The ecology and evolution of plant reproductive strategies

植物繁殖策略影响基因传递、种群统计和进化多样化的净速率。了解这些策略的进化和生态学是理解达尔文的“可恶之谜”的关键——开花植物的快速多样化和优势地位的上升。本提案的短期目标是发展我们对植物克隆和进化以及性别空间隔离的理解。这两个专题在其概念基础方面没有实质性发展，因而受到冷落。我们对植物无性系的认识尤其需要修正；无性系植物分布广泛，往往具有生态优势，但对无性系的生态成本和效益的研究远远落后于其他生殖方式。对于性别的空间隔离（即种群内雌性和雄性之间的隔离；具有独立性别的植物的普遍特征），关于隔离如何影响生殖适应性的理论和实验很少。这里提出的研究旨在通过新理论的发展，并通过严格的现场实验结合分子遗传技术对这一理论进行测试，来重新定义我们对这些概念的理解。我们的问题是：(i)与广泛持有的观点相反，与非无性系植物相比，无性系是否能促进生殖适应性？（ii）空间隔离是否对生殖适宜性有负面影响，这些影响对雌性和雄性是否相同？为了回答这些问题，我们也将对核心进化理论进行一些首次直接测试。总之，这一建议旨在改变我们对植物无性系和雌雄植物分离的理解，并推进对基本但很少被测试的生物学概念的认识。这些短期目标直接有助于实验室的长期目标，即了解调节植物生殖策略进化转变的生态过程，从而揭示调节开花植物多样性的过程。

Plant reproductive strategies influence gene transmission, population demography, and net rates of evolutionary diversification. Understanding the evolution and ecology of these strategies is key to understanding Darwin's 'abominable mystery' - the rapid diversification and rise to dominance of the flowering plants. The short-term goals of this proposal are to develop our understanding of the ecology and evolution of plant clonality and spatial segregation of the sexes. These two topics have languished without substantive developments in their conceptual underpinnings. Our understanding of plant clonality in particular needs revision; clonal plants are widespread and often ecologically dominant but studies of the ecological costs and benefits of clonality lag far behind that of other reproductive modes. For spatial segregation of the sexes (i.e., segregation between females and males within populations; a widespread feature of plants with separate sexes) there has been no theory and very little experimentation on how segregation affects reproductive fitness. The research proposed here aims to reset our understanding of these concepts via development of new theory and via tests of this theory using rigorous field experimentation in combination with molecular-genetic techniques. We ask: (i) can clonality promote reproductive fitness in comparison with non-clonal plants, contrary to widely-held views? and (ii) does spatial segregation have negative consequences for reproductive fitness, and are these consequences equal for females vs. males? In answering these questions, we will also be conducting some of the first direct tests of core evolutionary theory. Taken together, this proposal aims to transform our understanding of plant clonality and the segregation of female and male plants and to advance knowledge of fundamental, but rarely tested biological concepts. These short-term objectives contribute directly to the lab's long term goal of understanding the ecological processes regulating evolutionary transitions in plant reproductive strategy and thereby revealing processes that regulate flowering plant diversity.