RUI: Conflicting selection pressures within mate choice of Jewelwing damselflies

RUI：珠宝翅豆娘的择偶压力存在冲突

• 批准号: 2242987
• 负责人: Idelle Cooper
• 金额: $ 44.83万
• 依托单位: Grinnell College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2027-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2242987&HistoricalAwards=false
• 关键词: RUI; Conflicting; selection; pressures; within

One hundred and fifty years after Darwin described the origin of species as the consummate mystery, biologists are still seeking to unravel fundamental questions of speciation, including how mate choice evolves. The process of choosing a mate is central to species identities, but it can involve two steps that may conflict: identifying which potential mate is the same species and selecting which one is most attractive. The choice might be different for those two processes, and the chosen mate might end up being a different species, particularly if a nearby, closely-related species is brighter, flashier, louder, or otherwise more appealing. When that happens, species boundaries can break down and two species can become one. Alternatively, natural selection to maintain species boundaries may act against selection for the most attractive mate. A key to understanding speciation and biodiversity, therefore, is to explore how conflicting decisions in mate choice are resolved. This project will examine selection on damselfly wing pigmentation, a trait used when choosing mates. Overall, this project will train undergraduate students in field ecology and in public outreach through the development of an art exhibit that will explore complexity and diversity of form in nature. This project leverages a natural experiment involving two Jewelwing damselfly species, Calopteryx aequabilis and C. maculata, whose geographic ranges overlap. Wing pigmentation varies within and between species. Where the species live separately, they look very similar, but where they coexist their wing pigmentation is quite different. This pattern suggests that conflicting selection is acting on wing pigmentation. The PI will use a wing-transplant technique to switch wings between individuals from different populations and species and measure mate choice in paired choice trials across the species ranges. Additionally, the PI will measure the traits correlated with mating success in nature by marking damselflies with flourescent powder that transfers between mates. These approaches will pinpoint the traits under selection and the direction of selection by species recognition versus sexual selection. By studying both steps of mate choice along a gradient of species overlap, this research will reveal where and how conflicting choices may be resolved. The PI hypothesizes that sexual dimorphism, or differences between sexes, may resolve the conflict: females are under stronger species recognition selection and males are under stronger sexual selection, so a single trait under selection during mate choice may evolve readily in different directions.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.

在达尔文将物种起源描述为完美之谜150年后，生物学家仍在寻求揭开物种形成的基本问题，包括配偶选择是如何进化的。选择配偶的过程是物种认同的核心，但它可能涉及两个可能相互冲突的步骤：识别哪个潜在的配偶是同一个物种，以及选择哪个最有吸引力。对于这两个过程，选择可能是不同的，选择的配偶可能最终是不同的物种，特别是如果附近的密切相关物种更聪明、更华丽、更响亮，或者更有吸引力。当这种情况发生时，物种的界限可能会被打破，两个物种可以成为一个物种。或者，维持物种边界的自然选择可能会对最有吸引力的配偶的选择产生不利影响。因此，了解物种形成和生物多样性的关键是探索如何解决配偶选择中相互冲突的决定。这个项目将考察对蜻蜓翅膀色素的选择，这是选择配偶时使用的一种特征。总体而言，该项目将通过开发一个探索自然界形式的复杂性和多样性的艺术展览，对本科生进行田野生态学和公共宣传方面的培训。这个项目利用了一项自然实验，涉及两个地理范围重叠的珠翅蜻蜓物种：Calopteryx aequbilis和C.maculata。翅的色素沉着在种内和种间各不相同。在这两个物种分开生活的地方，它们看起来非常相似，但在它们共存的地方，它们的翅膀色素沉积却截然不同。这种模式表明，相互冲突的选择作用于翅膀的色素沉积。PI将使用翅膀移植技术在来自不同种群和物种的个体之间交换翅膀，并在跨物种范围的配对选择试验中测量配偶选择。此外，PI还将测量自然界中与交配成功相关的特征，方法是用在交配对象之间传递的荧光粉末标记豆娘。这些方法将通过物种识别和性别选择来确定选择下的特征和选择的方向。通过沿着物种重叠的梯度研究配偶选择的两个步骤，这项研究将揭示在哪里以及如何解决相互冲突的选择。PI假设性别二态或性别差异可能解决冲突：女性处于更强的物种认知性选择之下，而男性处于更强的性选择之下，因此在配偶选择过程中被选择的单一性状可能会很容易向不同方向进化。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。