The acronym Mhc, major histocompatibility complex, is customarily not allied with topics in evolutionary biology. Here, however, we attempt to demonstrate that the Mhc has much to offer to this discipline and intimate that evolutionary biologists who ignore its contributions miss out on a chance of applying a new approach to vexing questions. One aspect of the Mhc in particular affords a fresh look at the population processes that transform one species into another: the trans-species polymorphism, the passage of allelic lineages from ancestral to descendant species. We provide examples of using the Mhc polymorphism in estimating the size of the founding population of new species, and of analyzing the long-term population demographies of phylogenetic lineages. We then extend the concept of trans-species polymorphism to other genes, even those not evolving under balancing selection, and argue that the phenomenon is widespread between closely related species. On the example of the cichlid fishes of Lake Victoria, we demonstrate how the concept changes the interpretation of this so-called "species flock." We contend that the conclusions reached regarding the cichlid fishes apply also to other examples of adaptive radiation, for example that of Darwin's finches, and so provide new insights into the nature of speciation in general.

中文翻译：

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MHC，TSP和物种起源：从免疫遗传学到进化遗传学。

首字母缩写词Mhc是主要的组织相容性复合体，通常与进化生物学的主题无关。但是，在这里，我们试图证明Mhc可以为该学科提供很多帮助，并暗示忽略其贡献的进化生物学家会错过使用新方法来解决问题的机会。Mhc的一个方面尤其让人们重新审视了将一个物种转变为另一个物种的种群过程：跨物种多态性，等位基因谱系从祖先物种传给后代物种。我们提供了使用Mhc多态性来估计新物种的创始种群大小以及分析系统进化谱系的长期种群人口统计数据的示例。然后，我们将跨物种多态性的概念扩展到其他基因，即使是那些没有在平衡选择下进化的物种，也认为这种现象在密切相关的物种之间很普遍。以维多利亚湖的丽鱼科鱼类为例，我们演示了该概念如何改变了对这种所谓“物种群”的解释。我们认为，有关丽鱼科鱼类的结论也适用于其他适应性辐射的例子，例如达尔文雀科的，从而为一般物种的形成提供了新的见识。