New Jurassic bird fossil from China shows gradual tail evolution

A newly discovered Jurassic bird fossil reveals an intermediate tail structure, shedding light on a key evolutionary step towards modern bird flight. The 150-million-year-old Zhengheornis buyu fossil from China shows a tail with fewer vertebrae than dinosaurs but lacks the fused pygostyle of modern birds, suggesting a gradual tail reduction process. This finding challenges theories of a rapid evolutionary leap and indicates significant experimentation with body plans among early birds during the Late Jurassic period.