Chen Runsheng, Wang Min, Dong Liping, Zhou Guowu, Xu Xing, Deng Ke, Xu Liming, Zhang Chi, Wang Linchang, Du Honggang, Lin Ganmin, Lin Min, Zhou Zhonghe
Fujian Institute of Geological Survey, Fuzhou, China.
Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China.
Nature. 2025 Feb;638(8050):441-448. doi: 10.1038/s41586-024-08410-z. Epub 2025 Feb 12.
Recent macroevolutionary studies predict a diversification of early birds during the Jurassic period, but the unquestionable Jurassic bird fossil record is limited to Archaeopteryx, which has also been referred to deinonychosaurian dinosaurs by some analyses. Although they have feathered wings, the known Jurassic birds are more similar to non-avialan theropods in having the ancestral long reptilian tail. This is in stark contrast to most Cretaceous and crownward taxa, which have a short tail that terminates in a compound bone called the pygostyle. Here we report on the oldest short-tailed avialan, Baminornis zhenghensis gen. et sp. nov., from the recently discovered Late Jurassic Zhenghe Fauna, which fills a noticeable spatio-temporal gap in the earliest branching avialan fossil record. B. zhenghensis exhibits a unique combination of derived ornithothoracine-like pectoral and pelvic girdles and plesiomorphic non-avialan maniraptoran hand, demonstrating mosaic evolution along stem avialan line. An avialan furcula collected from the same locality is referrable to ornithuromorphs on the basis of our morphometric and phylogenetic analyses. These newly discovered fossils demonstrate the early appearance of highly derived bird features, and together with an anchiornithine fossil from the same locality, they suggest an earlier origin of birds and a radiation of early birds in the Jurassic.
近期的宏观进化研究预测，在侏罗纪时期早期鸟类会出现多样化，但确凿的侏罗纪鸟类化石记录仅限于始祖鸟，一些分析也将其归类为恐爪龙类恐龙。尽管已知的侏罗纪鸟类拥有带羽毛的翅膀，但它们在拥有祖先的长型爬行动物尾巴这一点上，与非鸟翼类兽脚亚目恐龙更为相似。这与大多数白垩纪及更高级别的类群形成鲜明对比，后者的尾巴很短，末端是一块叫做尾综骨的复合骨。在此，我们报道了来自最近发现的晚侏罗世政和动物群中最古老的短尾鸟翼类——郑氏始孔子鸟（Baminornis zhenghensis gen. et sp. nov.），它填补了最早分支的鸟翼类化石记录中一个明显的时空空白。郑氏始孔子鸟展现出了类似鸟类胸廓的特化肩带和腰带与原始的非鸟翼类手盗龙手部的独特组合，显示出沿鸟翼类主干谱系的镶嵌进化。基于我们的形态测量和系统发育分析，从同一地点采集到的一块鸟翼类叉骨可归为今鸟型类。这些新发现的化石证明了高度特化的鸟类特征的早期出现，并且与来自同一地点的近鸟龙化石一起，表明鸟类起源更早，且在侏罗纪时期早期鸟类就已辐射演化。
