Genetic exchange between divergent evolutionary lineages, from introgressive hybridization between locally adapted populations to insertion of retroviral sequences into eukaryotic genomes, has now been documented. The detection of frequent divergence-with-gene-flow contrasts the neo-Darwinian paradigm of largely allopatric diversification. Nevertheless, of even greater significance is the growing wealth of data suggesting that the recipients of the transferred genomic material gain adaptive phenotypes from the donor lineages. This adaptive enrichment is reflected by changes in pathogenicity in viruses and bacteria, the transformation of ecological amplitude in eukaryotes, and adaptive radiations in extremely diverse lineages. Although genetic exchange may produce maladaptive consequences, most of the recently reported examples suggest increases in fitness, and many such adaptive trait transfers have been identified in our own species.

从局部适应群体之间的渐渗杂交到逆转录病毒序列插入真核基因组的不同进化谱系之间的遗传交换，现已被证明。与基因流频繁发散的检测与很大程度上是异相发散的新达尔文主义范式形成了鲜明的对比。然而，更重要的是越来越多的数据表明转移的基因组材料的接受者从供体谱系获得了适应性表型。这种适应性富集通过病毒和细菌的致病性变化，真核生物中生态幅度的转变以及极为不同的谱系中的适应性辐射得以反映。尽管基因交换可能会产生适应不良的后果，