Macroevolutionary Consequences of Staminode Evolution in Integrated Floral Systems of Mentzelia section Bartonia (Loasaceae)

植物生物学中的一项主要创举是专注于了解进化过程，这些进化过程产生了看似无穷无尽的花。花可以被看作是专门结构的综合系统，其功能是优化生殖成功，包括花粉传播、花粉接收和种子生产。花在进化过程中经历了特殊的形态变化，包括新的、非可育结构的多重起源，包括退化雄蕊。退化雄蕊是不发育的雄蕊或不育雄蕊，它们是从花粉产生中获得的，用于执行新的功能，如产生花蜜、吸引授粉者或增强花粉的扩散或沉积。因此，这些结构提供了一个理想的系统来研究功能共选下的综合性状进化。这个项目将通过研究耀眼的星星中的花的进化来测试当一个结构被增选来执行新的功能时，是否有一个进化反应来补偿生殖功能的损失。许多受训者将参与该项目，与俄亥俄州第一学者计划的合作将把来自代表性不足群体的两名第一代学生纳入研究计划。48名早期职业科学家将在全国研究会议上通过两个讲习班接受系统发育比较方法方面的培训。将创建一个专注于植物进化的教育视频和学习模块，以促进对这个重要但鲜为人知的概念的科学素养，这个概念需要创新资源。花由整合的部分组成，其功能是最大限度地繁殖，但当花的一部分被选为执行新功能时，人们对宏观进化的后果知之甚少。在黄豆科Mentzelia组Bartonia中，雄蕊花丝反复进化成不育的花瓣状退化雄蕊，为决定功能互补的进化反应提供了一个特殊的系统。该项目将应用系统发育比较方法，对退化雄蕊共同选择对花结构的进化后果提供关键的见解，包括雄蕊、雌蕊和花瓣结构内部和之间的相互作用。该项目解决了五个主要的研究问题：(1)裸子植物Bartonia组退化雄蕊的进化史是什么；(2)退化雄蕊是与剩余的花结构整合在一起的；(3)退化雄蕊进化时是否有利于对生殖输出的补偿；(4)退化雄蕊是否与环境因素相关；(5)退化雄蕊是如何影响不同花型的雄性和雌性适合度的？为了回答这些问题，该组织的进化史将通过基因组数据进行推断，并与环境和植物数据相结合，以确定性状如何变化和共同变化，以及它们在进化史上的整合程度。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

A major initiative in plant biology is focused on understanding the evolutionary processes that have generated the seemingly endless forms of flowers. Flowers can be viewed as integrated systems of specialized structures that function to optimize reproductive success, including pollen dispersal, pollen reception, and seed production. Flowers have experienced extraordinary morphological changes through evolutionary time, including multiple origins of novel, non-fertile structures, including staminodes. Staminodes are rudimentary stamens or sterile stamens that were co-opted from pollen production to perform novel functions, such as nectar production, pollinator attraction, or enhanced pollen dispersal or deposition. These structures therefore provide an ideal system to study integrated-trait evolution in response to functional co-option. This project will test whether there is an evolutionary response to compensate for the loss of reproductive function when a structure is co-opted to perform a novel function by studying floral evolution in the blazingstars. Numerous trainees will participate in the project, and a collaboration with the Ohio First Scholar program will integrate two first-generation students from underrepresented groups into the research program. Forty-eight early career scientists will be trained in phylogenetic comparative methods through two workshops at a national research conference. An educational video and learning module focused on plant evolution will be created to promote science literacy in this important but poorly understood concept that requires innovative resources.Flowers are composed of integrated parts that function to maximize reproduction, but little is known about the macroevolutionary consequences when one part of the flower is co-opted to perform a novel function. In Mentzelia section Bartonia (Loasaceae), stamen filaments have repeatedly evolved to become sterile, petal-like staminodes, providing an exceptional system to determine the evolutionary response of functional co-option. This project will apply phylogenetic comparative approaches to provide key insights into the evolutionary consequences of staminode co-option on floral structures, including interactions within and among the male, female, and petal structures. The project addresses five main research questions: (1) What is the evolutionary history of staminodes in Mentzelia section Bartonia; (2) are staminodes integrated with the remaining floral structures; (3) does evolution favor compensation of reproductive outputs when staminodes evolve; (4) are staminodes correlated with environmental factors; and (5) how do staminodes affect male and female fitness across different floral forms? To answer those questions, the evolutionary history of the group will be inferred with genomic data and combined with environmental and floral data to determine how traits vary and covary, as well as their level of integration across evolutionary history.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.