Science & Tech · Science & Environment · 2 hrs ago
Fossil of a flightless Jurassic bird challenges ideas about bird evolution
Researchers in China have identified a new, apparently flightless Jurassic bird from a nearly complete fossil found in Fujian Province.
Named Yuezhuornis yangyuanensis, it lived about 148 million to 150 million years ago and was roughly the size of a large crow.
Its shorter forelimbs and longer hindlimbs suggest it was built more for life on the ground than for flight.
The fossil also has a long tail and serrated teeth like those of some dinosaurs, alongside bones resembling those of later birds.
This mix suggests early bird anatomy did not develop in a straight line toward flight.
The researchers say early birds may have quickly adapted to different ways of life, including ones that did not involve flying.
The discovery challenges the idea that the demands of flight were the main force shaping the early bird body plan.
Researchers say a newly described Jurassic bird from China was flightless, challenging the idea that flight drove the evolution of the early bird body plan.
Named Yuezhuornis yangyuanensis, the almost-complete fossil is about 148 million to 150 million years old.
Its anatomy combines features of birds and non-avian dinosaurs, and researchers say it was similar in some ways to modern ground-dwelling pheasants.
The researchers’ analysis suggests Archaeopteryx, considered a stronger flier, was more primitive than Yuezhuornis.
They say early birds rapidly developed different body forms and lifestyles, including ones that did not involve flight.
- Who
- Researchers led by Min Wang of the Chinese Academy of Sciences described Yuezhuornis yangyuanensis.
- What
- They reported a fossil of a flightless Jurassic bird with a mix of bird and dinosaur features.
- When
- The fossil is about 148 million to 150 million years old. It was discovered in August 2024.
- Where
- Near Yangyuang village in Fujian Province, China.
- Why
- The researchers say the fossil challenges the idea that flight’s selective pressures almost exclusively drove the early evolution of the bird body plan.
This story does not have two clearly opposing sides.
The almost-complete fossil was discovered near Yangyuang village in Fujian Province, China.
Yuezhuornis yangyuanensis lived during the Late Jurassic, according to the fossil’s estimated age.
New Scientist reported the discovery and the researchers’ interpretation of the bird’s anatomy.
- Species
- Yuezhuornis yangyuanensis
- Fossil age
- About 148 million to 150 million years
- Discovery
- August 2024, near Yangyuang village, Fujian Province, China
- Estimated height
- Around half a metre
- Estimated weight
- Just over 800 grams
- Anatomy comparison
- Researchers compared it with nearly 400 living bird species
2 sources
What people are saying
This new fossil changes our assumption about what a Jurassic bird looked like.
[Y. yangyuanensis] exhibits a striking ‘mosaic’ of primitive and derived features – blending classic avian traits with distinct characteristics inherited from non-[avian] dinosaurs.