Collaborative Research: The evolution of phenotypic plasticity in sleep across variable environments

虽然睡眠在动物王国中几乎是普遍的，但睡眠模式和数量在物种之间差异很大。此外，个人会根据环境改变睡眠时间。虽然调节睡眠可能对动物的生存很重要，但人们对这种睡眠行为的可塑性是如何进化的知之甚少。影响动物睡眠时间的一个生态因素是食物供应。一些物种减少睡眠是为了应对食物匮乏的环境，可能是为了增加觅食的时间。然而，其他人在这些条件下增加睡眠，这可能是一种在没有食物时保存能量的策略。这被称为睡眠可塑性。这项工作探讨了睡眠可塑性的演变使用盲墨西哥洞穴鱼作为焦点物种。通过量化洞穴鱼在不同季节的自然栖息地中的睡眠，研究人员将自然发生的可变环境条件与动物的睡眠量联系起来。此外，睡眠可塑性将在来自洞穴鱼和他们的表面鱼对应物的交叉检查，允许检查睡眠可塑性的遗传基础。总之，这些研究将提供前所未有的洞察力，了解睡眠可塑性是如何以及为什么进化的，睡眠可塑性如何受到环境变量的影响，以及潜在的遗传对睡眠可塑性的影响。将利用迷人的cavefish系统，通过为本科生开发研究密集型课程和为高中生开发夏季研究指导计划来吸引学生。最后，与FAU的Osher终身学习研究所合作，将促进退休公民对科学研究的理解，并为当地退休人员提供研究机会。生物体根据环境因素调节睡眠，显示出睡眠可塑性。 睡眠可塑性的一个突出例子是在不同营养可用性条件下观察到的睡眠变化。该项目旨在了解墨西哥洞穴鱼Astyanax mexicanus睡眠可塑性进化的遗传基础。在实验室条件下，洞穴鱼的睡眠比同种表层鱼少。当饥饿时，表面和洞穴鱼有相反的反应：表面鱼减少睡眠，而洞穴鱼增加睡眠。这项研究计划将测试一个假设，即洞穴鱼已经进化出睡眠丧失和改变睡眠可塑性，以应对洞穴环境，在不同季节的食物供应强烈变化。睡眠可塑性和进化之间的关系在一个可变的环境中使用三种方法检查：1）将评估从多个洞穴种群产生的表面-洞穴杂种和洞穴-洞穴杂种，以阐明睡眠可塑性的遗传结构，并鉴定该性状进化的候选基因，2）睡眠，进食，和食物的可利用性将在三个不同的洞穴鱼包含洞穴中跨季节进行测量，以定义自然栖息地中的这些行为，并确定这些行为进化的环境条件，和3）将对同一洞穴内不同池塘中的鱼类进行基因组和行为分析，这些池塘的食物供应量不同，以揭示单个洞穴内行为进化的遗传基础。该奖项反映了NSF的法定使命，并被认为值得通过利用基金会的智力价值进行评估来支持和更广泛的影响审查标准。

While sleep is almost universal across the animal kingdom, sleep patterns and amount vary drastically between species. Further, individuals alter how much they sleep in response to their environments. While modulating sleep is likely important for an animal's survival, little is known about how this plasticity in sleeping behavior evolves. One ecological factor that affects how much an animal sleeps is food availability. Some species reduce sleep in response to a food-poor environment, presumably to increase the time available for foraging. However, others increase sleep under these conditions, which is likely a strategy to conserve energy when food is not available. This is referred to as sleep plasticity. This work examines the evolution of sleep plasticity using the blind Mexican cavefish as a focal species. By quantifying sleep in cavefish in their natural habitats across seasons, the researchers will connect naturally occurring, variable environmental conditions to the amount animals sleep. Further, sleep plasticity will be examined in crosses derived from cavefish and their surface fish counterparts, allowing for examination of the genetic basis of sleep plasticity. Together, these studies will provide unprecedented insight into how and why sleep plasticity has evolved, how sleep plasticity is impacted by environmental variables, and the underlying genetic influences on sleep plasticity. The captivating cavefish system will be leveraged to engage students through the development of a research-intensive course for undergraduates and a summer research mentoring program for high school students. Finally, a collaboration with FAU's Osher Lifelong Learning Institute will promote understanding of scientific research for retired citizens and provide research opportunities for local retirees.Organisms regulate sleep in response to environmental factors, displaying sleep plasticity. One striking example of sleep plasticity is the change in sleep observed under different nutrient availability conditions. This project aims to understand the genetic basis of the evolution of sleep plasticity in the Mexican cavefish, Astyanax mexicanus. Cavefish sleep less than conspecific surface fish under ad libitum fed laboratory conditions. When starved, surface and cavefish have opposite responses: surface fish reduce sleep whereas cavefish increase sleep. This research program will test the hypothesis that cavefish have evolved sleep loss and altered sleep plasticity in response to a cave environment that strongly varies in food availability across seasons. The relationship between sleep plasticity and evolution in a variable environment are examined using three approaches: 1) surface-cave hybrids and cave-cave hybrids generated from multiple cave populations will be evaluated to elucidate the genetic architecture underlying sleep plasticity and to identify candidate genes for the evolution of this trait, 2) sleep, feeding, and food availability will be measured in the field across seasons in three different cavefish-containing caves to define these behaviors in natural habitats, and to determine the environmental conditions under which these behaviors have evolved, and 3) genomic and behavioral analyses will be performed on fish from different pools within the same cave that vary in food availability to uncover the genetic underpinnings of behavioral evolution within a single cave.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.