Ever since Darwin (1), Huxley (2), and   Simpson (3), adaptive radiation (4) has been used as a major concept in evolutionary   biology. In this context, convergences in morphological, ecological, and   physiological characteristics are usually regarded as occasional curiosities,   i.e., the exception rather than the rule. However, most features whose   radiation has been studied were also the major characters used in the systematic   classification of the organisms bearing them. Characters can therefore be   circularly interpreted as showing lack of convergence through a phylogenetic   hypothesis inferred partly from these very same characters. The development   of molecular phylogenetics has contributed a major breakthrough in the study   of these radiations. For example, comparisons between morphological   characters and results of molecular phylogenetic analyses have demonstrated   extensive and multiple convergences of ecologically specialized species (i.e., ecomorphs)   of cichlid fishes (5, 6), plethodontid salamanders (7–9), Anolis lizards   (10), and mammals (cf. ref. 11 and references therein).

自达尔文（1）、赫胥黎（2）和辛普森（3）以来、适应性辐射（4）一直是进化论的一个主要概念。在这种情况下，形态、生态和生理特征的趋同通常被认为是偶然的奇怪现象，即例外而非规律。然而，在适应性辐射研究中的大多数特征也被用于对相关物种系统分类。因此，通过一个部分由这些非常相同的特征推断出的系统发育假说，可以循环地解释这些特征显示出缺乏趋同性。分子系统学的发展促进这些适应性辐射的研究提供了重大突破。例如，形态特征和分子系统发育分析结果之间的比较已经证明了丽鱼科鱼（5，6）、无肺螈科（7–9）、安乐蜥（10）和哺乳动物（参考文献11及其参考文献）的生态特化种（即生态形态）的广泛和多重趋同。