Late Tertiary Climatic Changes and the Evolutionary Success of Tribe Senecioneae (Asteraceae): A Phylogenetic Approach

晚第三纪气候变化和千里光族（菊科）的进化成功：系统发育方法

• 批准号: 0917809
• 负责人: Linda Watson
• 金额: $ 11.67万
• 依托单位: Oklahoma State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-11-21 至 2011-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0917809&HistoricalAwards=false
• 关键词: Late; Tertiary; Climatic; Changes; Evolutionary

The plant tribe Senecioneae is a large group of plants in the Asteraceae (Sunflower) family, with approximately 3000 described species worldwide. It has an almost cosmopolitan distribution and harbors enormous diversity in morphological adaptations. Yet there has been no attempt to reconstruct the evolutionary relationships within this enormous plant group despite the numerous and detailed studies on the Asteraceae as a whole and for all other tribes in this family, thereby creating a large gap in our understanding of one of the largest families of vascular plants. The aim of the proposed research is to improve our understanding of the evolutionary success of Senecioneae by reconstructing its evolutionary history and by examining the origin of summer-dry / winter-wet habitats (mediterranean climates) in which so many members of this group live; such climates appeared between 2 and 6 million years ago and resulted in regions with specialized floras on five continents. Utilizing biogeographic and molecular dating methods, the time and place of origin for the Senecioneae will be estimated, and dispersal pathways leading from ancestral area(s) into regions with Mediterranean climates will be reconstructed and dated. The patterns of diversification that subsequently followed colonization into Mediterranean regions will be further examined and routes of migration into areas with other climates will be inferred. Thus, it will be determined if the descendents of Mediterranean lineages remained confined to these summer-dry areas, or alternatively, became main elements of other contemporary floras. A final goal is to use the reconstructed relationships of Senecioneae as a basis for a new classification for the tribe that reflects evolutionary history. The merits of this proposal will be a better understanding of the evolution of Mediterranean-climate plants, in general, by providing insight into the relationship between climate change and diversification. Furthermore, this project will contribute to a better understanding of the evolution of one of the largest, most diverse, and successful families of flowering plants.The impacts of this research include contributions to the education of students and teachers through research training, to the general public through the increased availability of information on the Internet, as well as to the scientific community through publication in journals and presentations. The proposed research will give opportunities for Miami University of Ohio students to complete their research requirements for graduation, and opportunities for graduate students to serve as research mentors. In addition, the proposed research will be available to students who apply to the University's Summer Scholars Program and to in-service primary and secondary school teachers in the Masters of Teaching Program. Photographs, descriptions, phylogenies, and nomenclatural information will be incorporated into the Tree of Life website for access by the general public with links to important databases. Similarly, information will be provided for the website of The International Compositae Alliance, an international consortium of scientists studying the evolution of the sunflower family.

千里光族是菊科（向日葵）植物的一个大类群，全世界约有3000种。它几乎是世界性的分布，在形态适应上具有巨大的多样性。然而，尽管对菊科作为一个整体以及该科中的所有其他部落进行了大量详细的研究，但并没有试图重建这个巨大植物群内的进化关系，从而在我们对维管植物最大的家族之一的理解中造成了很大的差距。拟议的研究的目的是通过重建其进化历史和研究夏季干燥/冬季潮湿栖息地（地中海气候）的起源来提高我们对千里光族进化成功的理解，这些栖息地中有如此多的千里光族成员生活;这样的气候出现在200万至600万年前，并导致五大洲的地区拥有专门的植物群。利用地理和分子测年方法，千里光族的起源时间和地点将估计，并从祖先地区（S）到地中海气候地区的传播途径将重建和日期。将进一步审查随后在地中海区域殖民化之后的多样化模式，并推断向其他气候地区移徙的路线。因此，将确定地中海血统的后裔是否仍然局限于这些夏季干燥的地区，或者成为其他当代植物区系的主要成分。最终的目标是使用重建的千里光族的关系作为一个新的分类的部落，反映了进化历史的基础。 这一建议的优点是，通过深入了解气候变化与多样化之间的关系，将更好地了解地中海气候植物的演变。 此外，该项目将有助于更好地了解最大，最多样化和成功的开花植物家族之一的进化。该研究的影响包括通过研究培训对学生和教师的教育做出贡献，通过增加互联网上的信息提供对公众做出贡献，以及通过在期刊上发表和发表演讲向科学界介绍。拟议的研究将为俄亥俄州的迈阿密大学的学生提供完成毕业研究要求的机会，并为研究生提供担任研究导师的机会。此外，拟议的研究将提供给谁申请到大学的夏季学者计划的学生和在职中小学教师在教学硕士课程。照片、描述、命名和命名信息将被纳入生命之树网站，供公众访问，并链接到重要的数据库。 同样，还将为国际菊科联盟的网站提供信息，该联盟是一个研究向日葵家族进化的国际科学家联合会。