Developmental Basis of Convergent Evolution of Drosophila Pigmentation Patterns

在不同的动植物物种中，相似的解剖结构和生理过程独立进化是很常见的。这种现象(称为收敛进化)反映了这样一个事实，即相似的生态压力施加了相似的功能要求；换句话说，每个任务都需要一个特定的工具。尚不清楚的是，趋同进化的特征是否具有相同的遗传和分子基础。有可能不同的分子途径可以被选入不同的进化谱系中，以产生表面上相似的结构和适应。这一假说将通过识别导致几种果蝇(果蝇)颜色模式进化变化的基因来验证。果蝇被选为这项研究的模型，因为这种昆虫的遗传和分子实验容易且成本低。如果发现不同的基因在不同的物种中产生相似的颜色模式，这将表明自然选择可以利用不同的变异来源来实现相同的功能结果。相反的发现表明，自然选择的作用受到控制动物发育的遗传途径内在结构的制约。鉴于了解人类病原体、农业害虫和其他影响人类社会和经济的生物物种的适应过程日益重要，解决进化中的偶然性和必然性之间的相互作用将有助于制定生物和化学控制战略。该项目的另一个目标是培训准备在全基因组范围内带头分析分子变异的年轻科学家，并将其与解剖和生理特征以及环境因素联系起来。这种培训对于人类医学、农业、林业和生物技术的进一步发展至关重要。这个项目将为学生提供一个获得第一手研究经验的机会，并通过实际应用最新概念和技术来补充理论教育，扩大他们的职业选择。

It is common for similar anatomical structures and physiological processes to evolve independently in different species of animals and plants. This phenomenon (known as convergent evolution) reflects the fact that similar ecological pressures impose similar functional requirements; in other words, each task calls for a specific tool. What is not clear is whether convergently evolved traits share the same genetic and molecular basis. It is possible that different molecular pathways can be co-opted in different evolutionary lineages to produce superficially similar structures and adaptations. This hypothesis will be tested by identifying the genes responsible for evolutionary changes in color patterns in several species of fruit flies (Drosophila). Drosophila has been chosen as a model for this research due to the ease and low cost of genetic and molecular experimentation in this insect. If different genes are found to produce similar color patterns in different species, it will indicate that natural selection can utilize different sources of variation to achieve the same functional outcome. An opposite finding will suggest that the action of natural selection is constrained by the inherent structure of genetic pathways that control animal development. Given the increasing importance of understanding adaptive processes in human pathogens, agricultural pests, and other biological species that affect human society and economy, resolving this interplay between chance and necessity in evolution will help in the development of biological and chemical control strategies. An additional goal of this project is to train young scientists prepared to take the lead in analyzing molecular variation on genome-wide scales, and relating it to anatomical and physiological traits and environmental factors. Such training is essential for further advances in human medicine, agriculture, forestry, and biotechnology. This project will provide an opportunity for students to acquire first-hand research experience and expand their career options by complementing theoretical education with a practical application of the latest concepts and techniques.