DISSERTATION RESEARCH: Evaluating likelihood-based fossil-calibraition methods and timing of repeated incercontinental dispersal in a fossil-rich clade of Boraginaceae

论文研究：评估基于可能性的化石校准方法以及在富含化石的紫草科进化枝中反复大陆扩散的时间

• 批准号: 1210833
• 负责人: Bruce Baldwin
• 金额: $ 1.49万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2014-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1210833&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Evaluating; likelihood; based

Fossils are routinely used as the most defensible method for calibrating phylogenetic hypotheses to absolute time. Calibration is often required before ideas can be tested, such as timing of a prehistoric event or rate of change of a trait. This project examines a fossil rich plant group, the Cryptanthinae (Boraginaceae), to test two recently proposed but untested methods for incorporating fossils in phylogenetic analyses. After evaluating these methods, the resulting time-calibrated hypothesis of phylogenetic relationships will be used to examine the New World amphitropical disjunction, a distribution pattern seen in the Cryptanthinae and many other groups of plants that is likely the result of long-distance dispersal by birds between North and South America. This project will result in three main contributions to science. First, evaluation of novel methods for incorporating fossil data into phylogenetic studies will benefit all future studies using fossil data. Importantly, these methods can be generalized to any study using morphological data. Second, New World amphitropical disjunction is common yet understudied. This study will test current hypotheses regarding this biogeographic pattern. Finally, this project will generate a hypothesis of relationships in the Cryptanthinae that will inform taxonomy and conservation in this large and ecologically important plant group.

化石通常被用作将系统发育假设校准至绝对时间的最可辩护的方法。在测试想法之前，通常需要进行校准，例如史前事件的时机或性状变化率。该项目研究了一个富化石植物群，即cryptanthinae（Boraginaceae），以测试两种最近提出的，但未经测试的方法，用于将化石纳入系统发育分析。在评估了这些方法之后，将使用系统发育关系的时间校准假设来检查新世界的两性跨性别脱节，这种分布模式在Cryptanthinae和许多其他植物组中都可能是北美和南美之间鸟类长距离散布的结果。 该项目将为科学带来三个主要贡献。首先，将化石数据纳入系统发育研究中的新型方法的评估将使使用化石数据的所有未来研究受益。重要的是，这些方法可以推广到使用形态学数据的任何研究。其次，新世界的两性脱节是常见的尚未研究的。这项研究将检验有关此生物地理模式的当前假设。最后，该项目将产生隐态性关系的假设，该假设将为这个大型且在生态上重要的植物群中提供分类学和保护。