Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island 02906, USA.
Nat Commun. 2012 Jan 24;3:637. doi: 10.1038/ncomms1642.
Archaeopteryx has been regarded as an icon of evolution ever since its discovery from the Late Jurassic limestone deposits of Solnhofen, Germany in 1861. Here we report the first evidence of colour from Archaeopteryx based on fossilized colour-imparting melanosomes discovered in this isolated feather specimen. Using a phylogenetically diverse database of extant bird feathers, statistical analysis of melanosome morphology predicts that the original colour of this Archaeopteryx feather was black, with 95% probability. Furthermore, reexamination of the feather's morphology leads us to interpret it as an upper major primary covert, contrary to previous interpretations. Additional findings reveal that the specimen is preserved as an organosulphur residue, and that barbule microstructure identical to that of modern bird feathers had evolved as early as the Jurassic. As in extant birds, the extensive melanization would have provided structural advantages to the Archaeopteryx wing feather during this early evolutionary stage of dinosaur flight.
自从 1861 年在德国索伦霍芬的晚侏罗世石灰岩矿床中发现始祖鸟以来，它一直被视为进化的象征。在这里，我们报告了始祖鸟颜色的第一个证据，这是基于在这个孤立的羽毛标本中发现的已矿化的赋予颜色的黑素体。使用现生鸟类羽毛的系统发育多样化数据库，对黑素体形态的统计分析预测，这只始祖鸟羽毛的原始颜色为黑色，概率为 95%。此外，对羽毛形态的重新检查使我们将其解释为上主翼羽覆羽，与之前的解释相反。其他发现表明，该标本保存为有机硫残留物，而且早在侏罗纪时期，就已经进化出与现代鸟类羽毛相同的羽小枝微观结构。与现生鸟类一样，广泛的黑色素沉着会为始祖鸟的翼羽在恐龙飞行的这个早期进化阶段提供结构优势。
