Fossils provide direct evidence for the molecular evolution of bird feathers

January 28th, the results of a study entitled "Direct Evidence of Fossil Evolution of Feather Molecules" by Yan Hong, an associate researcher at the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences, were published online in the Proceedings of the National Academy of Sciences (PNAS), providing molecular biological evidence for exploring the evolution of early feathers. Zhou Zhonghe, a member of the Institute of Paleontology and Paleoanthropology of the Chinese Academy of Sciences, Professor Zheng Xiaoting of Linyi University and Professor Mary Schweitzer of North Carolina State University participated in the study.
the study showed that while hairy dinosaurs, represented by near-bird dragons, may have some ability to fly, the molecular composition of their feathers is not enough to support a flight similar to that of birds.
modern birds are mainly composed of β-keratin, a structural protein that gives it special biometric properties such as flexibility, elasticity and strength to suit the needs of flight. Do the feathers of bird ancestors have the same protein composition and structure? The answer to this question can not only reveal the process of early feather molecular evolution, but also provide new clues to the study of the flight ability of feathered dinosaurs.
researchers used a variety of modern ultrastructur detection techniques, in-place element analysis and immunology methods to conduct in-depth research and comparison of feather fossils of near-bird dragons from the Jurassic formation in China (about 160 million years ago). The results show that the fly feathers of near-bird dragons are mainly composed of α-keratin, but also have a small amount of β-keratin, which is different from the feathers of modern birds. However, the feathers of birds found in the Meso-Descendants of China, such as the original Confucius birds, swallows and a new generation of bird fossils, are mainly composed of β-keratin, which is consistent with modern birds.
results suggest that the feathers of near-bird dragons represent the transition of early feathers from unfit for flight to the evolution of feathers of living birds in the composition of protein molecules.
study further highlights the importance of integrating multidisciplinary data and research in morphology, developmental science, and molecular biology to explore major biological evolution events. It is generally believed that the organic molecules that make up the organism, with the degradation process, the original stable chemical bonds are destroyed and thus no longer exist. However, with the development of various analytical techniques in recent years, more and more large molecular fossils have been discovered. Keratin has better buried potential than most other proteins, mainly due to its specific molecular structure.
The team's previous research confirmed that β-keratin does remain in the fossilized bird feathers, supporting the presence of fossilized birds and dinosaur feather pigments, so this study represents the latest developments in related research. (Source: Science Network Shen Chunlei)