OPUS: MCS: Mechanisms and evolution of premating reproductive isolation along a speciation continuum

作品：MCS：沿物种形成连续体的交配前生殖隔离的机制和进化

• 批准号: 1950302
• 负责人: Jeanne Robertson
• 金额: $ 28.45万
• 依托单位: The University Corporation, Northridge
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2024-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1950302&HistoricalAwards=false
• 关键词: OPUS; MCS; Mechanisms; evolution; premating

A central question in evolutionary biology is how and why a trillion forms of life, both living and extinct, have emerged. Speciation—the formation of new species— can proceed when two groups of organisms no longer recognize each other as mates due to differences in relevant traits such as behavior (e.g., songs) or appearance (e.g., coloration). This research quantifies the behavioral and neural mechanisms that mediate female mate recognition and preference to understand how speciation proceeds. Researchers will measure female response to males from differentiated populations of the same species (pre-speciation stage) and to males of two closely related species (post-speciation stage), thus spanning a continuum of species-level differentiation. Researchers will first conduct behavioral studies to identify the strength and role of relevant traits in courtship and mating success at each stage. Next, female response will be linked to activation patterns in the regions of the brain associated with visual, acoustic and courtship processing. Examination of neural de-activation patterns in the courtship region of the brain along the speciation continuum addresses a gap in knowledge of whether speciation proceeds gradually or abruptly. This research builds upon 17 years of genetic and behavioral studies of the Neotropical red-eyed treefrog, Agalychnis callidryas, to understand the mechanisms and processes of early-stage speciation. It supports diverse students to experience science in the field and in the lab, and creates active-learning content for ~120 students in an enrichment program at the K5 grade level (82% underserved minority, 60% Free/Reduced Lunch). Finally, this research fosters international collaboration between U.S. and Costa Rican research biologists.This collaborative research provides new and exciting insights into the evolution of signal divergence, female recognition and neural activity patterns, and the consequences of these factors for premating reproductive isolation and speciation. This research has two specific aims. Aim 1 examines female response to divergent cues through both female preference assays and neural activation patterns to test whether incremental increases in trait divergence result in a continuous or all-or-none neural response. Aim 2 tests how mismatched cues alter neural activity response patterns, addressing whether mismatched cues weaken/break courtship response. Neural response will be measured using immunohistochemistry and microscopy. Combined, these two aims identify how the trait(s) that are important for stimulating courtship behavior modulate neural activity function, and thus provide mechanistic insight into how premating reproductive isolation evolves. Computational modeling will explore the dynamic relationship among signal differentiation and female response (behavior and neural activity) using simulated data.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.

进化生物学的一个核心问题是如何以及为什么出现了数万亿人的生活形式，无论是生命还是灭绝。当两组有机体不再彼此识别为伴侣，由于相关性状（例如，歌曲（例如歌曲）或外观（例如着色），规格 - 新物种的形成 - 可以进行。这项研究量化了介导女性伴侣识别的行为和神经机制，以了解规范如何进行。研究人员将衡量女性对同一物种分化人群（特殊阶段）和对两个密切相关物种（特殊阶段）的男性的反应，从而跨越了物种级别的分化。研究人员将首先进行行为研究，以确定相关特征在每个阶段的求爱和交配成功中的力量和作用。接下来，女性反应将与与视觉，声学和求爱处理相关的大脑区域的激活模式有关。对大脑求爱区域的神经去激活模式的检查沿着规范的检查继续探讨有关规范是逐渐还是突然进行的知识差距。这项研究建立在新的红眼蛙（Agalychnis callidryas）的17年遗传和行为研究基础上，以了解早期规范的机制和过程。支持潜水员的学生在现场和实验室中体验科学，并在K5年级的一项丰富计划中为约120名学生创建积极学习的内容（82％服务不足的少数族裔，60％的免费/减少午餐）。最后，这项研究促进了美国和哥斯达黎加研究生物学家之间的国际合作。这项合作研究为信号差异，女性认可和中性活动模式的演变以及这些因素的后果提供了新的令人兴奋的见解，以及这些因素的后果。这项研究具有两个具体的目标。 AIM 1考试通过女性偏好分析和神经元激活模式对女性对不同线索的反应，以测试性状差异的增量增加是否会导致连续或全部或全或无人神经元反应。 AIM 2测试不匹配的提示如何改变神经元活动反应模式，以解决不匹配的提示是否弱/断裂求爱响应。将使用免疫组织化学和显微镜测量神经反应。这两个目标结合在一起，确定了对于刺激求爱行为的特征如何调节神经元活动的功能，从而提供了对预测生殖隔离演变的机理洞察力。计算建模将使用模拟数据探索信号分化和女性反应（行为和神经元活动）之间的动态关系。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响来评估，被认为是宝贵的支持。