Developmental Mechanisms of Beak Shape Evolution in Galapagos Finches

达尔文的雀是自然选择进化的经典教科书例子。 自从查尔斯达尔文将这些鸟类引入科学以来，它们已经被一代又一代的生态学家和进化生物学家研究。 先前的研究表明，它们不同的喙形状具有适应性意义，这使它们能够在不同的食物来源中生存。然而，这些高度适应性的生物形状背后的遗传和分子机制仍然未知。 Abzhanov博士及其同事最近证明，达尔文雀的喙多样性不是随机的，而是遵循一系列特定的数学转换，它们所有的喙都可以归类为一组相关的几何形状。 该项目旨在通过测序、比较和分析与达尔文雀不同喙形发育有关的多个基因，揭示精确的分子机制。 预计重要的新的调控分子将被识别和验证功能实验。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遗传变化来解释。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、学校教师和科学新闻作家以及将最重要的发现带给科学和普通公众的科学家们的头脑中的进化提供一个更机械的解释。研究人员将与每年有数万名K-12学生和教师参加的哈佛大学自然历史博物馆合作，建立一个关于鸟类进化的新教育展览，重点是从爬行动物条件下出现的鸟脸和随后的喙多样化，以解释进化过程。最后，该项目将促进本科生、研究生和博士后研究员的培训和指导，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.