Molecular Systematics of the Verbenaceae

马鞭草科（马鞭草科）是新世界植物区系的一个重要组成部分，大约有1000种，主要分布在南美洲的顶端到美国西南部，有的物种向北延伸到加拿大、欧洲和非洲。在拉丁美洲，从热带潮湿的森林到温带的沙漠再到安第斯山脉的高山生态系统都有。这些植物分布的一个特别有趣的方面是，在北美和南美的干旱地区有几个属的不间断分布，它们之间有几千英里的距离。这些植物的分类是混乱和过时的，最近没有系统的研究试图整合整个家族。该项目将对整个家族的物种进行采样，使用几个核和叶绿体基因的DNA序列来重建该植物家族的系统发育，并使用关系树来构建更具预测性的分类，并测试其中物种起源和分布的假设。拨款将支持实地和实验室研究。生物分类是科学家用来交流地球上生命多样性的语言。理解物种间进化关系的分子方法的发展，使得建立一致的分类基础方法成为可能。因此，这项研究的一个重要结果将是对这类植物进行更有用的分类，供全世界的科学家使用。植物分布的模式与其发生的环境条件密切相关。马鞭草科植物在北美和南美干旱地区出现了多样化。其中一个可以解释这种模式的假设是，过去的气候变化将曾经连续分布的地区分成了两个广泛分离的地区。了解植物分布的历史模式和可能导致它们的过程可能有助于科学家了解在我们正在进入的预期气候变化时期植被的潜在变化。由于这组植物的大部分多样性都发生在拉丁美洲，奥姆斯特德博士已经与中美洲和南美洲几个机构的科学家建立了合作关系。预计此次科学交流将通过研究生交换（至少一名华盛顿大学研究生将前往拉丁美洲，一名阿根廷研究生将前往西雅图）和合作发表研究成果，使美国和这些机构的科学家个人受益。

The Verbena family (Verbenasceae) is an important element in the New World flora, with approximately 1,000 species distributed primarily from the tip of South America to the SW US and with species extending as far north as Canada, Europe, and Africa. In Latin America it occurs from tropical wet forests to temperate deserts to high Andean ecosystems. One particularly interesting aspect of the distribution of these plants is the disjunct distribution of several genera between the arid regions of North America and South America, with a gap of several thousand miles between them. The classification of these plants is confusing and out of date with no recent systematic studies attempting to integrate across the entire family. This project will sample species throughout the family use the DNA sequences of several nuclear and chloroplast genes to reconstruct the phylogeny of this plant family and to use that tree of relationships to construct a more predictive classification and to test hypothesis of the origin and distribution of the species therein. The grant will support both field and laboratory research.Biological classification is the language with which scientists communicate about the diversity of life on earth. The development of molecular approaches to understanding evolutionary relationships among species has permitted the establishment of consistent methods for the basis of classification. Thus, one significant result of this research will be a more useful classification of this group of plants for scientists worldwide to use. Patterns of plant distribution are tightly linked to environmental conditions where they occur. Plants in family Verbenaceae have diversified in arid in North and South America. One of the hypotheses that may explain this pattern postulates past climate change that has segregated what was once a continuous distribution into two widely separated regions. Understanding the historical patterns of plant distributions and the processes that may have given rise to them may help scientists to understand the potential changes in vegetation during the anticipated climate change period we are now entering. Since most of the diversity of this group of plants occurs in Latin America, Dr. Olmstead has established collaborations with scientists at several institutions in Central and South America. It is anticipated that this scientific exchange will benefit individual scientists both in the US and at those institutions through graduate student exchange (at least one University of Washington grad student will travel to Latin America and one Argentine grad student will travel to Seattle) and collaborative publication of the research results.