Collaborative Research: Genomic and phenotypic analyses of color pattern divergence in a mimetic radiation of poison frogs

自然界中有大量的生物体显示明亮的颜色，但并不总是显而易见的原因。有些动物进化为向潜在的捕食者宣传它们有毒（警告色）。不同的有毒物种可能会聚集在同一种颜色模式上，通过更有效地向捕食者宣传，使两者都具有优势。这被称为穆勒拟态，一个感兴趣的焦点，因为它涉及到多种现象，这些现象是我们理解进化过程的核心。拟态的遗传基础特别有趣，因为它为了解这些关键的进化过程提供了一个窗口。这项研究的重点是发现一种毒蛙的穆勒拟态的遗传基础，这种毒蛙在秘鲁不同的地理区域经历了进化辐射。在每一个地区，模仿毒蛙已经进化出不同的颜色模式（如条纹，带或斑点），以模仿该地区的另一个物种。这些新的颜色模式的进化可能会推动模仿毒蛙种群之间的生殖隔离，导致物种形成和创造新的生物多样性。该项目是三所大型公立大学研究人员之间的合作奋进，将涉及本科生和研究生以及博士后科学家的广泛参与。该项目的成果将用于通过课堂演示，公共讲座和博物馆展示来加强K12教育。该项目的重点是四个具体目标：1。通过研究不同发育阶段和颜色模式形态的差异基因表达，确定参与模拟毒蛙颜色模式发育的关键遗传因素，使用下一代测序为每个形态产生阶段特异性转录组，这些转录组将被组装以分析差异基因表达模式。2.使用全基因组标记阵列（外显子组捕获序列）来筛选过渡区样品（来自三个过渡区）并使混合物作图能够发现候选基因，从而鉴定变体之间颜色模式差异的潜在因果基因。3.使用多代家系测试特定候选基因座与颜色模式的关联。4.使用新的分析工具，测试有关过渡区以及模拟和模型之间的选择和人口统计过程的特定假设。这些互补，相互加强的方法将阐明遗传基础和种群基因组学的颜色模式的演变和多样性，在这种模仿辐射的毒蛙。

Nature abounds with organisms that display bright colors, yet it is not always obvious why. Some animals evolve to advertise to potential predators that they are poisonous (warning coloration). Different toxic species may converge on the same color pattern, giving both an advantage by more effectively advertising to predators. This is known as Müllerian mimicry, a focus of interest because it involves multiple phenomena that lie at the heart of our understanding of evolutionary processes. The genetic basis of mimicry is of special interest, because it provides a window into how these key evolutionary processes unfold. This research will focus on discovering the genetic underpinnings of Müllerian mimicry in a species of poison frog that has undergone an evolutionary radiation across different geographic regions of Peru. In each region, the mimic poison frog has evolved a different color pattern (such as stripes, bands, or spots), to resemble another species in that region. The evolution of these new color patterns may be driving reproductive isolation between populations of the mimic poison frog, leading to speciation and the creation of new biodiversity. The project is a collaborative endeavor between researchers at three large public universities and will involve broad participation by undergraduate and graduate students, and a postdoctoral scientist. The results of the project will be used to enhance K12 education through classroom presentations, public lectures and museum displays. This project focuses on four specific aims: 1. Identify key genetic factors involved in color pattern development in the mimic poison frog by investigating differential gene expression across developmental stages and color pattern morphs, using next generation sequencing to produce stage-specific transcriptomes for each morph, which will be assembled to analyze patterns of differential gene expression. 2. Identify the causal gene(s) underlying differences in color pattern between morphs using genome-wide marker arrays (exome capture sequences) to screen transition zone samples (from three transition zones) and enable admixture mapping to discover candidate genes. 3. Test the association of specific candidate loci with color pattern using multigenerational pedigrees. 4. Test specific hypotheses regarding selection and demographic processes in the transition zones and between mimics and models, using new analytical tools. Together these complementary, mutually reinforcing approaches will elucidate the genetic underpinnings and population genomics of color pattern evolution and diversity in this mimetic radiation of poison frogs.