Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester, UK.
Syst Biol. 2010 May;59(3):245-61. doi: 10.1093/sysbio/syp106. Epub 2010 Jan 15.
The relationship between morphometrics and phylogenetic analysis has long been controversial. Here we propose an approach that is based on mapping morphometric traits onto phylogenies derived from other data and thus avoids the pitfalls encountered by previous studies. This method treats shape as a single, multidimensional character. We propose a test for the presence of a phylogenetic signal in morphometric data, which simulates the null hypothesis of the complete absence of phylogenetic structure by permutation of the shape data among the terminal taxa. We also propose 2 measures of the fit of morphometric data to the phylogeny that are direct extensions of the consistency index and retention index used in traditional cladistics. We apply these methods to a small study of the evolution of wing shape in the Drosophila melanogaster subgroup, for which a very strongly supported phylogeny is available. This case study reveals a significant phylogenetic signal and a relatively low degree of homoplasy. Despite the low homoplasy, the shortest tree computed from landmark data on wing shape is inconsistent with the well-supported phylogenetic tree from molecular data, underscoring that morphometric data may not provide reliable information for inferring phylogeny.
形态计量学和系统发育分析之间的关系一直存在争议。在这里，我们提出了一种方法，该方法基于将形态特征映射到源自其他数据的系统发育树上，从而避免了先前研究中遇到的陷阱。该方法将形状视为单个多维特征。我们提出了一种检验形态计量数据中是否存在系统发育信号的方法，该方法通过在终端分类单元之间对形状数据进行置换来模拟完全没有系统发育结构的零假设。我们还提出了 2 种衡量形态计量数据与系统发育关系的拟合度的方法，这是传统系统发育学中使用的一致性指数和保留指数的直接扩展。我们将这些方法应用于一个关于黑腹果蝇亚组翅膀形状进化的小型研究中，该研究提供了一个非常支持的系统发育树。这个案例研究揭示了一个显著的系统发育信号和相对较低的同形性程度。尽管同形性较低，但从翅膀形状的地标数据计算出的最短树与来自分子数据的支持良好的系统发育树不一致，这强调了形态计量数据可能无法为推断系统发育提供可靠的信息。
