Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
PLoS One. 2012;7(5):e36745. doi: 10.1371/journal.pone.0036745. Epub 2012 May 22.
The precise phylogenetic relationships of many non-hadrosaurid members of Iguanodontia, i.e., basal iguanodonts, have been unclear. Therefore, to investigate the global phylogeny of basal iguanodonts a comprehensive data matrix was assembled, including nearly every valid taxon of basal iguanodont. The matrix was analyzed in the program TNT, and the maximum agreement subtree of the resulting most parsimonious trees was then calculated in PAUP. Ordering certain multistate characters and omitting taxa through safe taxonomic reduction did not markedly improve resolution. The results provide some new information on the phylogeny of basal iguanodonts, pertaining especially to obscure or recently described taxa, and support some recent taxonomic revisions, such as the splitting of traditional "Camptosaurus" and "Iguanodon". The maximum agreement subtree also shows a close relationship between the Asian Probactrosaurus gobiensis and the North American Eolambia, supporting the previous hypothesis of faunal interchange between Asia and North America in the early Late Cretaceous. Nevertheless, the phylogenetic relationships of many basal iguanodonts remain ambiguous due to the high number of taxa removed from the maximum agreement subtree and poor resolution of consensus trees.
许多禽龙类（非鸭嘴龙类），即基础禽龙类，的精确系统发育关系一直不清楚。因此，为了研究基础禽龙类的全球系统发育，我们构建了一个综合数据矩阵，其中包括了几乎每一个基础禽龙类的有效分类单元。该矩阵在 TNT 程序中进行了分析，然后在 PAUP 中计算了产生的最简约树的最大一致性子树。对某些多态特征进行排序，并通过安全分类简化排除分类单元，并没有显著提高分辨率。结果提供了一些关于基础禽龙类系统发育的新信息，特别是涉及到一些模糊或最近描述的分类单元，并支持了一些最近的分类修订，例如传统的“禽龙”和“鸭嘴龙”的分裂。最大一致性子树还表明亚洲戈壁原巴克龙与北美洲爱氏棱齿龙之间存在密切关系，支持了早期晚白垩世亚洲和北美洲之间动物群交流的假说。然而，由于从最大一致性子树中移除了大量的分类单元，以及共识树的分辨率较差，许多基础禽龙类的系统发育关系仍然不明确。
