Herbarium and Division of Biology, Kansas State University, Manhattan, Kansas 66506-4901 USA;
Am J Bot. 2002 Aug;89(8):1324-35. doi: 10.3732/ajb.89.8.1324.
The comparison of independent phylogenies is a valuable approach to the study of evolutionary pattern and process. Available data on eastern North American Phlox, including our recent ITS phylogeny, suggest that relationships are complicated in the group and that hybridization may have been a contributing factor. We used restriction site data from the chloroplast genome to develop a second phylogeny for eastern Phlox. Sampling was the same as that for the ITS study and consisted of 79 samples (including all 22 eastern Phlox species and most eastern subspecies, as well as multiple populations of many taxa). The resulting cpDNA phylogeny agrees with the ITS phylogeny in many respects, strengthening earlier conclusions. Nevertheless, incongruence between the trees is noteworthy: many samples, particularly of members of the P. pilosa and P. glaberrima complexes, are placed in different clades. A variety of tests were carried out to assess congruence in terms of topological patterns, character congruence, and homogeneity of data sets. Significant conflict between the phylogenies is discussed in light of the hypothesis that hybridization has affected relationships in this genus.
独立系统发育的比较是研究进化模式和过程的一种有价值的方法。包括我们最近的 ITS 系统发育在内的有关北美东部福禄考的现有数据表明，该类群的关系比较复杂，杂交可能是一个促成因素。我们利用叶绿体基因组的限制位点数据为东部福禄考建立了第二个系统发育。采样与 ITS 研究相同，包括 79 个样本（包括所有 22 种东部福禄考物种和大多数东部亚种，以及许多类群的多个种群）。所得 cpDNA 系统发育在许多方面与 ITS 系统发育一致，这增强了早期的结论。然而，两个树之间的不一致值得注意：许多样本，特别是 P. pilosa 和 P. glaberrima 复合体的成员，被放置在不同的分支中。进行了多种测试，以根据拓扑模式、性状一致性和数据集的同质性来评估一致性。根据杂交影响该属关系的假说，讨论了系统发育之间的显著冲突。
