During the 1960s and 1970s population geneticists pushed beyond models of single genes to grapple with the effect on evolution of multiple genes associated by linkage. The resulting models of multiple interacting loci suggested that blocks of genes, maybe even entire chromosomes or the genome itself, should be treated as a unit. In this context, Richard Lewontin wrote his famous 1974 book The Genetic Basis of Evolutionary Change, which concludes with an argument for considering the entire genome as the unit of selection as a result of linkage. Why did Lewontin and others devote so much intellectual energy to the “complications of linkage” in the 1960s and 1970s? We argue that this attention to linkage should be understood in the context of research on chromosomal inversions and co-adapted gene complexes that occupied mid-century evolutionary genetics. For Lewontin, the complications of linkage were an extension of this chromosomal focus expressed in the new language of models for linkage disequilibrium.

在 1960 和 1970 年代，群体遗传学家超越了单基因模型，努力解决与连锁相关的多个基因进化的影响。由此产生的多个相互作用基因座的模型表明，基因块，甚至可能是整个染色体或基因组本身，应该被视为一个单元。在这种背景下，Richard Lewontin 写了他 1974 年的著名著作《进化变化的遗传基础》，结论是一个论点，将整个基因组视为连锁的结果选择单位。为什么 Lewontin 和其他人在 1960 年代和 1970 年代将如此多的智力精力投入到“联系的复杂性”上？我们认为，这种对联系的关注应该在染色体倒位和共同适应基因复合物的研究背景下理解，这些复合物占据了世纪中叶的进化遗传学。对于 Lewontin 来说，连锁的复杂性是这种染色体焦点的延伸，这种染色体焦点以连锁不平衡模型的新语言表达。