RUI: Conflicting selection pressures within mate choice of Jewelwing damselflies

在达尔文将物种起源描述为完美之谜的150年后，生物学家仍在寻求解开物种形成的基本问题，包括配偶选择如何进化。选择配偶的过程是物种身份的核心，但它可能涉及两个可能相互冲突的步骤：确定哪个潜在配偶是同一物种，并选择哪个最有吸引力。这两个过程的选择可能是不同的，最终选择的伴侣可能是不同的物种，特别是如果附近，密切相关的物种更明亮，华丽，更响亮，或者更有吸引力。当这种情况发生时，物种界限可能会打破，两个物种可能会成为一个。另一方面，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，理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的冲突决定。这个项目将研究豆娘翅膀色素沉着的选择，这是选择配偶时使用的一个特征。总的来说，这个项目将通过开发一个艺术展览来培养本科生在野外生态学和公共宣传方面的能力，该展览将探索自然界形式的复杂性和多样性。该项目利用了一个自然实验，涉及两个宝石翅豆娘物种，Calopteryx aequabilis和C。maculata，其地理范围重叠。翅膀色素在物种内部和物种之间变化。在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，它们的翅膀色素是完全不同的。这种模式表明，冲突的选择是对翅膀色素沉着。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切换翅膀，并在物种范围内的配对选择试验中测量配偶选择。此外，PI将通过用在配偶之间转移的荧光粉标记豆娘来测量与自然界中交配成功相关的性状。这些方法将通过物种识别与性选择来确定选择下的性状和选择方向。通过沿着物种重叠的梯度研究配偶选择的两个步骤，这项研究将揭示冲突的选择可能在哪里以及如何解决。PI假设性的二态性，或性别之间的差异，可以解决冲突：雌性受到较强的种识别选择，雄性受到较强的性选择，因此，在择偶过程中受到选择的单一性状可能会很容易地向不同的方向进化。该奖项反映了国家科学基金会的法定使命，并通过利用基金会的智力价值和更广泛的影响进行评估，被认为值得支持审查标准。

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.