Developmental Mechanisms of Beak Shape Evolution in Galapagos Finches

达尔文的雀类是自然选择进化的经典教科书。自从查尔斯·达尔文将这些鸟类引入科学研究以来，一代又一代的生态学家和进化生物学家对它们进行了研究。先前的研究显示了它们不同的喙形的适应性意义，这使它们能够在不同的食物来源上生存。然而，这些高度适应性生物形态背后的遗传和分子机制仍然未知。Abzhanov博士和他的同事最近证明，达尔文雀的喙的多样性不是随机的，而是遵循一系列特定的数学转换，它们所有的喙都可以分类为一系列相关的几何形状。该项目旨在通过测序、比较和分析涉及达尔文雀不同喙形发育的多个基因，揭示精确的分子机制。预计将有重要的新调控分子通过功能实验得到鉴定和验证。因此，生物多样性既可以用自然选择的力量来解释，也可以用使这种适应成为可能的特定基因变化来解释。这项工作与长期以来对达尔文雀的进化、生态和保护研究相结合，将为高中和大学教科书作者、学校教师、科学新闻作者和公关人员提供一个更机械的进化解释，他们将最重要的发现带给科学和普通公众。调查人员将与哈佛大学自然历史博物馆合作，每年有数以万计的K-12学生和教师参观，建立一个关于鸟类进化的新教育展览，重点关注鸟类面部从爬行动物状态的出现以及随后的喙多样化，以解释进化过程。最后，该项目将促进本科生、研究生和博士后的培训和指导，并将产生显著的研究和培训研究机会。

Darwin's Finches are a classic textbook example of evolution by natural selection. Since Charles Darwin, who introduced these birds to science, they have been studied by generations of ecologists and evolutionary biologists. Previous investigations have shown the adaptive significance of their diverse beak shapes, which allow them to survive on distinct food sources. However, the genetic and molecular mechanisms behind these highly adaptive biological shapes remained unknown. Dr. Abzhanov and colleagues recently demonstrated that beak diversity in Darwin's Finches is not random but follows a particular series of mathematical transitions and all their beaks can be classified as sets of related geometric shapes. This project aims to uncover the precise molecular mechanisms by sequencing, comparing and analyzing multiple genes involved in development of distinct beak shapes across Darwin's Finches. It is expected that important new regulatory molecules will be identified and validated using functional experiments. Therefore, biological diversity will be explained both by forces of natural selection and by particular genetic changes that made such adaptations possible. The integration of this work with the long-standing evolutionary, ecological and conservation studies on Darwin's Finches will provide a more mechanistic explanation for evolution in the minds of high school and college textbook writers, school teachers and science news writers and publicists who bring most significant findings to scientific and general public audiences. Investigators will work with the Harvard University Museum of Natural History, which is attended by tens of thousands of K-12 students and teachers each year, to establish a new educational exhibit on bird evolution that will focus on the emergence of the bird face from the reptilian condition and subsequent beak diversification to explain evolutionary processes. Finally, this project will advance training and mentoring of undergraduates, graduate students and post-doctoral fellows and will yield salient research and training research opportunities.