DISSERTATION RESEARCH: Phylogenesis of Hostshifts and Specialization in Neodiprion Sawflies

论文研究：新二叶蜂宿主转移和特化的系统发育

• 批准号: 0308815
• 负责人: Brian Farrell
• 金额: $ 1.06万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-01 至 2005-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0308815&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Phylogenesis; Hostshifts; Specialization

A grant has been awarded to Dr. Brian Farrell and Ms. Catherine Linnen at Harvard University to investigate the ecological and geographical circumstances under which new species arise. In particular, evolutionary biologists have long debated whether geographic barriers to reproduction are required for species formation. There is now convincing evidence that in plant-feeding insects, new species can arise in the absence of geographical barriers to reproduction (i.e., in sympatry) when individuals shift to a new host plant. But the role that this speciation mode has played in generating the staggering diversity of plant-feeding insects remains untested, as most studies have focused on single diverging or recently diverged species. The goal of this research is to understand the contribution that different speciation modes have made to contemporary diversity and to determine whether certain life history attributes (e.g., herbivory and dietary specialization) predispose organisms to particular speciation modes. These questions will be addressed in the sawfly genus Neodiprion (Hymenoptera: Diprionidae), a group of North American conifer-feeding insects that includes several pest species. Specifically, this study will elucidate the evolutionary relationships between species in the genus Neodiprion by examining interspecific variation in DNA sequences and morphological characteristics.The results of this study will provide important insights into the fundamental biological question: How and why do new species form? In addition, this research will contribute to our understanding of native and invasive species of Neodiprion and may uncover cryptic, host-specialized species within the genus. Upon completion of these studies, a database including museum specimens, publications, life history information, geographic range, and digital images for each Neodiprion species will be made publicly available via the World Wide Web.

哈佛大学的 Brian Farrell 博士和 Catherine Linnen 女士获得了一笔资助，用于调查新物种出现的生态和地理环境。 特别是，进化生物学家长期以来一直在争论物种形成是否需要繁殖的地理障碍。 现在有令人信服的证据表明，在以植物为食的昆虫中，当个体转移到新的寄主植物时，在没有地理繁殖障碍（即同域性）的情况下，可以出现新物种。 但这种物种形成模式在产生惊人的植物性昆虫多样性方面所发挥的作用仍未得到检验，因为大多数研究都集中在单一分化或最近分化的物种上。 这项研究的目的是了解不同的物种形成模式对当代多样性的贡献，并确定某些生活史属性（例如食草和饮食专门化）是否使生物体倾向于特定的物种形成模式。 这些问题将在锯蝇属（膜翅目：锯蝇科）中得到解决，这是一群北美针叶树食性昆虫，包括多种害虫物种。 具体来说，这项研究将通过检查 DNA 序列和形态特征的种间变异来阐明新二甲虫属物种之间的进化关系。这项研究的结果将为基本的生物学问题提供重要的见解：新物种如何以及为何形成？ 此外，这项研究将有助于我们了解新二甲虫的本地和入侵物种，并可能揭示该属内神秘的、宿主特化的物种。 这些研究完成后，将通过万维网向公众提供一个数据库，其中包括博物馆标本、出版物、生活史信息、地理范围和每个新二甲虫物种的数字图像。