进化速率分解揭示鸟类基因组变化驱动因素，这一成果由哥本哈根大学Simon Y. W. Ho 研究组经过不懈努力而取得。2025年3月19日出版的《自然》发表了这项成果。

通过对鸟类家族级系统发育的性状和进化速率的综合估计，该课题组发现跨谱系的全基因组突变率主要由窝代大小和世代长度来解释，而跨基因的突变率变化是由鸟嘌呤和胞嘧啶的含量驱动的。为了找到主导鸟类进化速率变化的基因和谱系亚群，该课题组人员估计了个体谱系对基因特异性进化速率分解轴的影响。课题组发现，大多数速率变化发生在这棵树最近的分支上，与当今的鸟类家族有关。对速率变化率轴的进一步测试表明，微染色体在白垩纪-古近纪过渡后立即发生了快速变化。这些明显的进化脉冲与减数分裂、心脏功能、RNA剪接、监视和翻译等遗传机制的主要变化一致，并与跗关节长度增加所反映的生态多样性相关。总的来说，他们的分析描绘了一幅细致入微的鸟类进化图景，揭示了鸟类最多样化谱系的祖先在古近纪早期经历了与突变、基因图谱和生态位扩张相关的重大基因组变化。

研究人员表示，现代鸟类在形态、行为和生态角色上已经呈现出惊人的多样化。分子进化速率的分析可以揭示基因组和表型变化之间的联系，但在全基因组尺度上解开速率变化的驱动因素一直很困难。

附：英文原文

Title: Drivers of avian genomic change revealed by evolutionary rate decomposition

Author: Duchne, David A., Chowdhury, Al-Aabid, Yang, Jingyi, Iglesias-Carrasco, Maider, Stiller, Josefin, Feng, Shaohong, Bhatt, Samir, Gilbert, M. Thomas P., Zhang, Guojie, Tobias, Joseph A., Ho, Simon Y. W.

Issue&Volume: 2025-03-19

Abstract: Modern birds have diversified into a striking array of forms, behaviours and ecological roles. Analyses of molecular evolutionary rates can reveal the links between genomic and phenotypic change1,2,3,4, but disentangling the drivers of rate variation at the whole-genome scale has been difficult. Using comprehensive estimates of traits and evolutionary rates across a family-level phylogeny of birds5,6, we find that genome-wide mutation rates across lineages are predominantly explained by clutch size and generation length, whereas rate variation across genes is driven by the content of guanine and cytosine. Here, to find the subsets of genes and lineages that dominate evolutionary rate variation in birds, we estimated the influence of individual lineages on decomposed axes of gene-specific evolutionary rates. We find that most of the rate variation occurs along recent branches of the tree, associated with present-day families of birds. Additional tests on axes of rate variation show rapid changes in microchromosomes immediately after the Cretaceous–Palaeogene transition. These apparent pulses of evolution are consistent with major changes in the genetic machineries for meiosis, heart performance, and RNA splicing, surveillance and translation, and correlate with the ecological diversity reflected in increased tarsus length. Collectively, our analyses paint a nuanced picture of avian evolution, revealing that the ancestors of the most diverse lineages of birds underwent major genomic changes related to mutation, gene usage and niche expansion in the early Palaeogene period.

DOI: 10.1038/s41586-025-08777-7

Source: https://www.nature.com/articles/s41586-025-08777-7