Collaborative Research: Unravelling the Dynamics of Mating-System Evolution in Tribe Collinsieae (Scrophulariaceae s.l.)

这项研究解决了关于植物交配系统进化的基本问题：(1)自花授粉为什么进化？(2)自交是否是进化的死胡同？(3)自交和异交策略能否可靠地通过特定的花特征来识别，例如自花授粉的时间？(4)特定交配系统的进化是否会导致花卉特征的可预测变化？研究人员将专注于研究上述问题的理想系统--Collinsieae部落，这是一种多种多样的本土一年生草本植物，显示出自交和异种繁殖策略之间反复进化的转变。这项研究将涉及实地和实验室研究，以利用遗传、发育和生态数据准确地解析整个部落群体的交配系统，并重建群体中交配系统变化的动态历史。自交进化是生物学家和遗传学家特别感兴趣的问题，他们很早就认识到，自交可以迅速导致遗传变异的丧失、有害特征的表现和进化潜力的丧失。为解释自交策略的进化而提出的不同(相互矛盾的)假设尚未得到充分的检验，自交谱系是否能产生具有长期进化前景的外交系这一基本问题仍未得到回答。解决这些问题将极大地推动进化生物学的发展，这也是这项研究的主要目标。

This study addresses fundamental questions about the evolution of plant mating systems: (1) Why does self-pollination evolve? (2) Is selfing an evolutionary dead-end? (3) Can selfing vs. outbreeding strategies be reliably identified by particular floral features, such as timing of self-pollination? (4) Does evolution of particular mating systems lead to predictable changes in floral characteristics? The investigators will focus on an ideal system for investigating the above questions--the tribe Collinsieae, a diverse group of native, annual herbs that show evidence of repeated evolutionary shifts between selfing and outbreeding strategies. The research will involve field and laboratory studies to resolve precisely the mating systems of populations throughout the tribe, using genetic, developmental, and ecological data, and to reconstruct the dynamic history of mating-system change in the group.Evolution of selfing is of special interest to biologists and geneticists, who have long recognized that it can rapidly cause the loss of genetic variation, expression of deleterious traits, and loss of evolutionary potential. Different (conflicting) hypotheses proposed to explain evolution of selfing strategies have not been adequately tested and the basic question of whether selfing lineages can spawn outbreeding lines with long-term evolutionary prospects remains unanswered. Resolving these issues would greatly advance evolutionary biology and is a primary goal of this investigation.