Fujianvenator prodigiosus, a missing link in bird evolution (Picture: Zhao Chuang)

A ‘bizarre’ fossil found in China has helped to fill a 30 million year gap in the evolution of birds.

Chinese scientists say the previously unknown species was a ‘high-speed runner’ who lived in a ‘swamp-like’ environment.

Present day birds had descended from theropod dinosaurs – two-legged dinosaurs with hollow bones – by the Late Jurassic period.

However, the exact process by which this happened has remained a mystery due to a lack of fossils from the Jurassic to the oldest known record of Cretaceous birds around 150 million years ago.

Now a Chinese team has described a 150-million-year-old avialan theropod found in Zhenghe County in Fujian Province, southeastern China.

They said the new species, named Fujianvenator prodigiosus, exhibits a strange mixture of features shared with other predecessors of today’s birds.

‘Our comparative analyses show that marked changes in body [shape] occurred along the early avialan line, which is largely driven by the forelimb, eventually giving rise to the typical bird limb proportion [wings],’ said lead author Dr Wang Min, of the Chinese Academy of Sciences in Beijing.

‘However, Fujianvenator is an odd species that diverged from this main trajectory and evolved bizarre hindlimb architecture.’

The early bird’s long legs mean it could have been a fast runner (Picture: Zhao Chuang)

He said the surprisingly long lower leg and other features suggest that Fujianvenator lived in a swamp-like environment and was a quick runner or a long-legged wader, representing a previously unknown version of early birds.

The researchers say that during the Late Jurassic–Early Cretaceous period, south eastern China underwent intensive tectonic activities, resulting in the unusual landscape where Fujianvenator was found.

The team say their findings, published in the journal Science, opens a ‘new window’ into the Late Jurassic terrestrial ecosystem of the planet, and they plan to continue their exploration of Zhenghe and nearby areas.

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It could be a missing link.