The mystery of bird ancestors: evolution from dinosaurs to birds
Currently, scientists widely believe that dinosaurs are the ancestors of birds. However, how did dinosaurs evolve from ground-dwelling creatures to the sky-dwelling beings we know as birds? This question remains an unsolved mystery. Fossil evidence regarding the origin of birds is scarce, with only a few primitive bird fossils, such as Archaeopteryx, discovered in Bavaria, Germany, dating back approximately 150 million years. The characteristics of Archaeopteryx lie between reptiles and birds, providing proof of the transition from reptiles to birds.
Within the academic community, there are two main theories: the arboreal theory and the terrestrial theory. The arboreal theory suggests that flying evolved from creatures that lived in trees through a gliding phase; the terrestrial theory posits that ground-dwelling animals learned to fly while running. Professor Ken Dial from the University of Montana observed that young birds flap their wings while climbing slopes, hypothesizing that the ancestors of birds may have learned to fly during running. Dr. Xu Xing from the Chinese Academy of Sciences supports the terrestrial theory but acknowledges the risks associated with this hypothesis.
Additionally, there is the question of how feathers on dinosaurs evolved into the feathers of birds. Since 1996, a series of dinosaur fossils have been discovered in western Liaoning, China, including the feathered dinosaur Confuciusornis and primitive birds, indicating that dinosaurs had feathers. Professor Kevin Padian from the University of California, Berkeley, points out that the four-winged dinosaur fossils provide significant evidence for the study of bird evolution in China, but more fossils are needed for confirmation. Some scientists remain cautious about the interpretation of four-winged dinosaur fossils, suggesting they may merely represent a side branch in the evolutionary process.
