China News Service, Beijing, April 24 (Reporter Sun Zifa) How did the birds that evolved from dinosaurs originate and evolve?
Related research has always attracted the attention of the paleontology community.
Scientists from China, Switzerland, and Germany have collaborated to study an ancient beak bird specimen from the Jehol Biota in the western Liaoning region of China about 120 million years ago, revealing an important stage in the evolution of birds.
The ancient beak bird was only the size of a pigeon, and because it did not develop teeth, it represented important evidence of the differentiation between modern toothless birds and anti-birds with teeth.
At the same time, the prosperous anti-birds with teeth in the Cretaceous Period (approximately 145 million to 66 million years ago) lived mainly on trees, and went extinct with the dinosaurs in the mass extinction event 66 million years ago.
The niche occupied by terrestrial birds that feed on seeds, such as ancient beak birds, allowed bird crowns to survive the Cretaceous-Paleogene (K-Pg) mass extinction.
This means that all birds today are the offspring of true birds that live on the ground and do not develop teeth that are similar to ancient beak birds.
Reconstruction of the growth stage of the ancient beak bird (the juvenile individual in the study on the left).
Photo courtesy of the research team
By Christian Foth, University of Fribourg, Switzerland, Wang Shiying, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Frederik Spindler and Liaoning The paper on the research results of ancient beak birds jointly completed by Lin Youhai and Yang Rui of the University of Engineering and Technology has recently been published in the international professional academic journal Frontiers in Earth Science.
Doctoral student Wang Shiying said in an interview with a reporter from China News Agency that for a long time, the Archaeopteryx discovered in Solenhofen in Germany has been the most important evidence for paleontologists to explore the origin of birds.
However, since the 1990s, a large number of feathered dinosaurs and primitive birds have been discovered in the Jehol Biota in China, providing more critical evidence for the origin and early evolution of birds.
The cooperative team recently conducted research on the fossil specimens of ancient beak birds in the Jehol Biota. They used red and blue imaging methods to take photos. The results were surprising: the bones and hairs were red and shiny, while the surrounding rocks remained gray.
After many adjustments, the fossil specimen showed a pseudo-color image, which not only provided the information needed for research, but also had a certain sense of beauty.
The researchers found through comparison that the fossil specimen should belong to the ancient-beaked bird, and that the body of the specimen is small and the degree of bone healing is low, which represents the juvenile stage of the ancient-beaked bird.
In addition, the anatomical features of this specimen are obviously suitable for walking on land, such as longer hind limbs, shorter toe claws and lower curvature.
A restored image of an ancient beak bird (drawn by Frederik Spindler).
Photo courtesy of the research team
Wang Shiying pointed out that the most important information of the ancient beak bird fossil specimens studied in this study comes from a group of black flying feathers.
Such a well-developed flying feather appears on a petite juvenile individual, which is a very unusual feature.
It shows that the ancient-beaked bird has a certain flying ability when its body size is significantly smaller than its mature body, while the living bird has reached its mature size when its body size is capable of flying.
In addition, the abdomen of the ancient beak bird fossil specimens contains some seed fossils that have not been completely digested, but the gastrolith is not preserved, and the larger ancient beak bird preserves the gastrolith.
The research team believes that studies of modern species-eating birds indicate that individuals at different stages of ontogeny may prefer seeds of different sizes, which suggests that ancient-beaked birds may have changed their feeding habits during their development.
(Finish)