Divergence time estimation of genus Tribolium by extensive sampling of highly conserved orthologs

Tribolium castaneum, the red flour beetle, is among the most well-studied eukaryotic genetic model organisms. Tribolium often serves as a comparative bridge from highly derived Drosophila traits to other organisms. Simultaneously, as a member of the most diverse order of metazoans, Coleoptera,  Tribolium informs us about innovations that accompany hyper diversity. However, understanding the tempo and mode of evolutionary innovation requires well-resolved, time-calibrated phylogenies, which are not available for Tribolium. The most recent effort to understand Triboliumphylogenetics used two mitochondrial and three nuclear markers. The study concluded that the genus may be paraphyletic and reported a broad range for divergence time estimates. Here we employ recent advances in Bayesian methods to estimate the relationships and divergence times among Tribolium castaneum, T. brevicornis, T. confusum, T. freemani, and Gnatocerus cornutus using 1368 orthologs conserved across all five species ...赤拟谷盗（Tribolium castaneum，俗称红面粉甲虫（red flour beetle））是研究最为深入的真核生物遗传模式生物之一。赤拟谷盗属（Tribolium）常被用作连接高度特化的果蝇（Drosophila）性状与其他生物的比较研究桥梁。同时，作为后生动物（metazoans）中物种多样性最高的类群鞘翅目（Coleoptera）的一员，赤拟谷盗属为我们揭示了伴随物种超多样化演化而来的适应性创新特征。然而，解析演化创新的速率与模式，需要构建分辨率优良且经时间校准的系统发育树（phylogenies），但目前赤拟谷盗属尚无此类完善的系统发育数据。此前针对赤拟谷盗属系统发育学的最新研究仅采用了2个线粒体标记与3个核标记，该研究指出该属可能为并系群（paraphyletic），并报道了跨度极大的分化时间估算结果。本研究借助贝叶斯方法（Bayesian methods）的最新进展，利用5个物种共有的1368个保守直系同源基因（orthologs），对赤拟谷盗、短角赤拟谷盗（Tribolium brevicornis，简称T. brevicornis）、混淆赤拟谷盗（Tribolium confusum，简称T. confusum）、弗里曼赤拟谷盗（Tribolium freemani，简称T. freemani）以及角扁谷盗（Gnatocerus cornutus）之间的系统发育关系与分化时间进行了估算……