A Comparative Study of Fitness Landscapes: Testing Competitive Disruptive Selection in Sticklebacks

即使在生态学中，“与众不同是值得的”。吃同样食物的动物会经历激烈的竞争，而使用不同资源的动物可能会避免竞争。因此，在一个给定的群体中，具有平均形态的个体可能比具有罕见形态的个体更不适合;这被称为“破坏性选择”。在之前的工作中，Bolnick博士证实竞争可以导致一种鱼类（棘鱼）的破坏性选择。当前项目的目标是确定这种破坏性选择是否常见。Bolnick博士将通过从20个湖泊捕获鱼类来测量许多棘鱼种群的自然选择，将它们的生长速度和繁殖潜力与它们的形态和饮食进行比较。破坏性选择的频率很重要，因为与其他类型的自然选择不同，它可以增强遗传多样性。这个项目将是第一次测试这种多样性增强过程是否在自然种群中普遍存在。这一结果可能具有实际意义：如果遗传多样性是通过竞争来维持的，那么许多受威胁物种的低种群密度可能会破坏它们的遗传变异性。该项目将为未来的高中科学教师提供研究经验，并用于有关进化论的公共教育。

Even in ecology, "it pays to be different". Animals that eat the same food as their fellows experience strong competition, while animals that use different resources may avoid competition. As a result, in a given population individuals with average morphologies may be less fit than individuals with rare morphologies; this is known as 'disruptive selection'. In previous work, Dr. Bolnick confirmed that competition can cause disruptive selection in a species of fish (sticklebacks). The goal of the current project is to determine whether this disruptive selection is common. Dr. Bolnick will measure natural selection in many populations of sticklebacks by capturing fish from 20 lakes, comparing their growth rate and reproductive potential to their morphology and diet. The frequency of disruptive selection is important because, unlike other types of natural selection, it can enhance genetic diversity. This project will be the first test of whether this diversity-enhancing process is common in natural populations. The result may have practical significance: if genetic diversity is maintained by competition, the low population densities of many threatened species might undermine their genetic variability. The project will provide future high-school science teachers with research experience, and be used for public education about evolution.