Molecular Systematics of the Lamiales

薄荷，薄荷科，是一个大的，经济和植物重要的家庭。他们被认为是一个“自然”的家庭，早在林奈之前就被认可了。然而，最近来自花粉形态、花和果实形态研究的证据表明，马鞭草科的各种成员可能是独立于马鞭草科的祖先进化而来的，因此，马鞭草科可能是多系的。如果是这样的话，那么Lamiaceae就代表了趋同进化的一个无与伦比的例子。用形态学来解释进化关系是有问题的。趋同进化这一现象被用来解释薄荷家族可能存在的错误界限，但它也可能导致关于关系的错误结论。从Lamiaceae和马鞭草科两个科的叶绿体DNA分子结构的比较分析中获得的新数据来源将被评估以解释其成员之间的进化关系模式。分子数据不容易受到趋同进化的误导，并且在最近的几项研究中已被证明是在这一水平上重建植物进化关系的有效方法。将采用两种方法：1)限制性内切位点定位将用于检查大量（约140个）物种；2)直接测序三个基因，这些基因编码的蛋白质在功能上与代表两个科中主要谱系的物种有很大不同。预计将从这项研究中获得的大量数据集将使用最近开发的计算机程序进行分析，这些程序旨在从分子数据中重建进化史。该研究将为植物分类学和进化生物学的发展提供依据，为重新划分兰科和马鞭草科提供依据。

The mints, family Lamiaceae, are a large, economically and floristically important family. They have been conceived to be a "natural" family and have been recognized since before Linneaus. However, recent evidence from studies of pollen morphology and floral and fruit morphology suggest that various members of the family may have evolved independently from ancestors in the family Verbenaceae and, therefore, the Lamiaceae would be polyphyletic. If this is the case, then the Lamiaceae represents an unparalleled example of convergent evolution. The use of morphology to interpret evolutionary relationships is problematic. The very same phenomenon that has been suggested to account for the possibly erroneous circumscription of the mint family, convergent evolution, could also result in erroneous conclusions about relationship. New sources of data derived from the comparative analysis of the molecular structure of the chloroplast DNA from both families, Lamiaceae and Verbenaceae, will be assessed to interpret the pattern of evolutionary relationship among their members. Molecular data is much less prone to the misleading effects of convergent evolution and has been shown to be effective for the reconstruction of evolutionary relationships at this level in plants in several recent studies. Two methods will be employed: 1) restriction site mapping will be used to examine a large number (ca. 140) of species and 2) direct sequencing of three genes coding for proteins differing greatly in function from species representing the major lineages within the two families. The very large data set expected to be derived from this research will be analyzed using recently developed computer programs designed to reconstruct evolutionary history from molecular data. This research will benefit both the fields of plant taxonomy, by providing the basis for a revised classification of the families Lamiaceae and Verbenaceae, and evolutionary biology, through the rigorous study of an outstanding example of convergent evolution.