2019年8月2日出版的《科学》杂志发表了美国科学家的一项最新研究成果。来自康奈尔大学的Nina O. Therkildsen研究组揭示应对人类捕捞行为，相同的鱼群表型进化背后不同的基因组改变。

研究人员在实验鱼群中追踪了所有蛋白编码基因的基因组变化，由于捕捞的大小选择性，这些鱼群的生长速率在仅仅4代中就进化出了明显的改变。研究人员比较平行实验后发现，平行等位基因频率发生变化，即在野外环境数百个无关联的突变富集在生长相关基因中，这反映了对大小选择梯度的响应。然而，只在其中一个平行实验组中有一大类基因的变化频率同样快速上升，并主导了进化动态性。因此，同等的表型变化掩盖了应对选择时高度不同的基因组反应，这提示在面临强烈的人为选择时，物种的快速适应性是如何地具有偶然性。

据悉，人类在自然界造成了广泛的进化改变，但在人类纪中快速适应性的基因组基础是什么还知之甚少。

附：英文原文

Title: Contrasting genomic shifts underlie parallel phenotypic evolution in response to fishing

Author: Nina O. Therkildsen, Aryn P. Wilder, David O. Conover, Stephan B. Munch, Hannes Baumann, Stephen R. Palumbi

Issue&Volume: Vol 365 Issue 6452

Abstract: Humans cause widespread evolutionary change in nature, but we still know little about the genomic basis of rapid adaptation in the Anthropocene. We tracked genomic changes across all protein-coding genes in experimental fish populations that evolved pronounced shifts in growth rates due to size-selective harvest over only four generations. Comparisons of replicate lines show parallel allele frequency shifts that recapitulate responses to size-selection gradients in the wild across hundreds of unlinked variants concentrated in growth-related genes. However, a supercluster of genes also rose rapidly in frequency and dominated the evolutionary dynamic in one replicate line but not in others. Parallel phenotypic changes thus masked highly divergent genomic responses to selection, illustrating how contingent rapid adaptation can be in the face of strong human-induced selection.

DOI: 10.1126/science.aaw7271

Source:https://science.sciencemag.org/content/365/6452/487