(ECNS) -- Chinese scientists have discovered the smallest known long-tailed bird to date, Zhengheornis buyu, according to the Institute of Vertebrate Paleontology and Paleoanthropology under the Chinese Academy of Sciences.
This finding provided the strongest fossil evidence to date that the reduction and shortening of tail vertebrae occurred before the formation of the fused tail bone during bird evolution.
For decades, many researchers believed there was likely no transitional species with a shortened tail that had not yet evolved a pygostyle.
The newly identified Jurassic bird, Zhengheornis buyu, overturns that long-held assumption.
Comparative analysis showed that Zhengheornis buyu has the shortest relative tail among all known long-tailed avialans. The finding provides compelling evidence that, in bird evolution, the reduction in both the number and length of tail vertebrae preceded the evolution of the pygostyle.
The study also identified Zhengheornis buyu as the smallest long-tailed avialan known to science.
Estimated to weigh between 74 and 163 grams and measuring about 20 centimeters in length, it had a femur only 63% the length of that of M. zhaoianus, previously regarded as one of the smallest known dinosaurs. It was about 10% smaller than the recently reported Chicago specimen of Archaeopteryx.
Its diminutive size suggests that some early bird-line dinosaurs underwent body-size reduction much faster than previously thought, likely as they adapted to new ecological niches such as arboreal habitats and powered flight.
The study, conducted by a team led by Wang Min from the institute in collaboration with the Fujian Institute of Geological Sciences, was published in the journal Science Advances on Thursday.
(By Zhang Dongfang)
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