Brower Andrew V Z
Section of Ecology and Systematics, Cornell University, Ithaca, New York, 14853.
Evolution. 1996 Feb;50(1):195-221. doi: 10.1111/j.1558-5646.1996.tb04486.x.
Mimicry has been a fundamental focus of research since the birth of evolutionary biology yet rarely has been studied from a phylogenetic perspective beyond the simple recognition that mimics are not similar due to common descent. The difficulty of finding characters to discern relationships among closely related and convergent taxa has challenged systematists for more than a century. The phenotypic diversity of wing pattens among mimetic Heliconius adds an additional twist to the problem, because single species contain more than a dozen radically different-looking geographical races even though the mimetic advantage is theoretically highest when all individuals within and between species appear the same. Mitochondrial DNA (mtDNA) offers an independent way to address these issues. In this study, Cytochrome Oxidase I and II sequences from multiple, parallel races of Heliconius erato and Heliconius melpomene are examined, to estimate intraspecific phylogeny and gauge sequence divergence and ages of clades among races within each species. Although phenotypes of sympatric races exhibit remarkable concordance between the two species, the mitochondrial cladograms show that the species have not shared a common evolutionary history. H. erato exhibits a basal split between trans- and cis-Andean groups of races, whereas H. melpomene originates in the Guiana Shield. Diverse races in either species appear to have evolved within the last 200,000 yr, and convergent phenotypes have evolved independently within as well as between species. These results contradict prior theories of the evolution of mimicry based on analysis of wing-pattern genetics.
自进化生物学诞生以来，拟态一直是研究的基本焦点，但除了简单认识到拟态者并非因共同祖先而相似之外，很少从系统发育的角度进行研究。一个多世纪以来，寻找特征以辨别近缘和趋同分类群之间的关系一直困扰着分类学家。模仿性的光明女神闪蝶翅膀图案的表型多样性给这个问题增添了额外的复杂性，因为即使当物种内部和物种之间的所有个体看起来相同时，拟态优势理论上最高，但单个物种仍包含十几个外观截然不同的地理种群。线粒体DNA（mtDNA）提供了一种独立的方法来解决这些问题。在这项研究中，对红带袖蝶和红袖蝶多个平行种群的细胞色素氧化酶I和II序列进行了检测，以估计种内系统发育，并衡量每个物种内各种群之间的序列分歧和进化枝的年代。尽管同域分布种群的表型在这两个物种之间表现出显著的一致性，但线粒体系统发育树表明这两个物种并没有共同的进化历史。红带袖蝶在安第斯山脉东西两侧的种群之间存在一个基部类群分裂，而红袖蝶起源于圭亚那地盾。这两个物种中的不同种群似乎都是在过去20万年中进化而来的，趋同的表型在物种内部以及物种之间都是独立进化的。这些结果与基于翅膀图案遗传学分析的先前拟态进化理论相矛盾。
