A tiny extinct bird that lived in China about 120 million years ago had a skull similar to the fearsome T.Rex, despite their stark difference in size.
Researchers analysed the freshly-discovered bird's skeleton, found in a shallow lake in the Jiufotang Formation in China’s Liaoning province.
The bird, which could have fit in the palm of a human hand, had a 'unique' 0.75-inch skull that shows a combination of dinosaur and bird-like features, they reveal.
Although the bloodthirsty T.Rex was far bigger – it reached to 40 feet in length and 12 feet in height – both shared a rigid, 'locked-up' skull.
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Photograph (left) and digital reconstruction (right) of the new Mesozoic bird fossil skeleton (scale bar: 10 mm)
Researchers analysed the bird's skeleton, found in a shallow lake in the Jiufotang Formation in China’s Liaoning Province
The research team, based at the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) in Beijing, performed computerised tomography (CT) scans and generated a 3D digital reconstruction of the fossilised bird skeleton.
Some of the earliest birds on this planet would have kept many features of their dinosaurian ancestors and their skulls functioned much like those of dinosaurs rather than living birds, the new skeleton suggests.
And through detailed reconstruction of the bird family tree, the researchers demonstrated that the specimen belongs to an extinct group of birds called enantiornithines, or 'opposite birds'.
They are the most diverse group of birds from the time of the dinosaurs in the Cretaceous period – 145 million to 66 million years ago – and have been found all over the world.
Opposite birds lived alongside the ancestors of modern birds and, archaeologists say, were more diverse and successful – until they were wiped out along with the dinosaurs 66 million years ago.
They had their origins before the famous T.Rex, which lived at the very end of the Late Cretaceous period, about 90 to 66 million years ago.
Key to this bird's unique combination of bird and dinosaur-like features was the quadrate.
In living birds, the quadrate is one of the most movable bones in the skull and allows the upper jaw to move independently of the brain and the lower jaw – known as a 'kinetic skull'.
But the skull of this newly found specimen, as well as those of dinosaurs like T.Rex and close dinosaurian relatives of birds (including troodontids and dromaeosaurs) was not kinetic – instead, its bones were 'locked up' and unable to move.
This new species was also shown to have two bony