Collaborative Research: BEE: Understanding Evolutionary Rescue

这项研究将探索进化如何拯救一个因环境急剧变化而灭绝的种群。当这些变化迅速时，生活在一个地方的植物、动物和其他生物可能会灭绝，特别是当种群数量很少且它们之间的移动很困难的时候。在某些情况下，快速适应变化的环境可以使这些小种群生长并避免灭绝。这个项目的重点是决定种群是否适应和持续存在或灭绝的因素，包括：地方的大小，种群的大小，种群的遗传变异量，以及地方之间的迁移是否可能。鉴于世界范围内正在发生的快速环境变化，所获得的信息对于成功管理濒危物种和入侵害虫将是至关重要的。本科生和研究生将参与研究，并通过科罗拉多州立大学昆虫动物园向公众宣传，以提高社会对保护和物种管理的理解。理论和实验表明，适应的速度足以防止或延缓物种灭绝：进化拯救的过程。大多数进化救援的实证研究使用单倍体微生物。然而，面临灭绝风险最大的物种是较大的二倍体生物。在这些物种中，有害等位基因的长期遗传变异很高，种群往往很小，相对于选择，更倾向于漂移和近亲繁殖。理论和实证研究往往未能考虑到生态过程中的随机性或抑制种群增长的过程，如密度依赖、遗传漂变和近亲繁殖，这些过程会抵消适应性进化的影响。研究人员将使用一个模型生物系统（Tribolium castaneum面粉甲虫）进行实验，与非进化控制相比，控制种群历史、大小、密度、扩散速度和扩散来源，并将检查适应性、灭绝和基因组多样性的后果。这些实验将与新的生态和进化模型相结合，这将有助于量化实验结果，并使研究推广到其他物种。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This research will explore how evolution can rescue a population from extinction due to drastic changes in the environment. When those changes are rapid, the plants, animals, and other organisms living in a place can go extinct, particularly when populations are small and movement between them is difficult. Under some circumstances, rapid adaptation to altered conditions can allow those small populations to grow and avoid extinction. This project focuses on the factors that determine whether populations adapt and persist or go extinct including: the size of the place, the size of the population, the amount of genetic variation a population has, and whether movement between places is possible or not. Given rapid environmental changes that are occurring worldwide, the information gained will be crucial for successful management of both endangered species and invasive pests. Undergraduate and graduate students will be involved in the research, and outreach to the public through the Colorado State University Bug Zoo will enhance societal understanding of conservation and species management.Theory and experiments show that adaptation can be rapid enough to prevent or delay extinctions: the process of evolutionary rescue. Most empirical studies of evolutionary rescue use haploid microorganisms. However, the species most at risk of extinction are larger diploid organisms. In these species, the standing genetic variation of deleterious alleles is high, and populations are often small, favoring drift and inbreeding relative to selection. Theoretical and empirical studies of rescue often fail to account for randomness in ecological processes or for processes that can inhibit population growth, such as density dependence, genetic drift, and inbreeding, which counter the effects of adaptive evolution. Using a model biological system (Tribolium castaneum flour beetles) the researchers will conduct experiments that manipulate population history, size, density, dispersal rate, and dispersal source, compared to non-evolving controls, and will examine consequences for fitness, extinction, and genomic diversity. The experiments will be paired with new, combined ecological and evolutionary models that will facilitate quantifying experimental results and allow the research to be generalized to other species.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.