A strange dinosaur called Archaeopteryx flew like a pheasant, advanced X-ray scans of its 150 million year old fossilised remains have revealed.
The question of whether the creature was an elaborately feathered ground dweller, a glider, or an active flyer has fascinated palaeontologists for decades.
Experts probed inside the raven sized beast, finding that the Jurassic creature flapped its wings but was not capable of long distance active flight.
Nor could it glide and soar, like modern-day birds of prey.
An international team of scientists used the European Synchrotron Radiation Facility (ESRF) in Grenoble, France, to perform state-of-the-art synchrotron microtomography.
The new study found that Archaeopteryx probably made short bursts of limited low-level flight to escape danger.
Present day pheasants adopt the same strategy when they take to the air to avoid predators, or gun-waving humans.
As part of the study, the ESRF X-ray beam was used to peer inside the bones of three Archaeopteryx specimens, without damaging the valuable fossils.
To take the scans, electrons were accelerated around a circular tunnel to generate X-rays 100 billion times more powerful than those in hospitals.
The X-rays can be employed to analyse the internal structure of numerous different materials, including fossils.
About the results, lead researcher Dennis Voeten, from ESRF, said: ‘We immediately noticed that the bone walls of Archaeopteryx were much thinner than those of earthbound dinosaurs but looked a lot like conventional bird bones.
‘Data analysis furthermore demonstrated that the bones of Archaeopteryx plot closest to those of birds like pheasants that occasionally use active flight to cross barriers or dodge predators, but not to those of gliding and soaring forms such as many birds of prey and some seabirds that are optimised for enduring flight.’
Archaeopteryx – which means ‘ancient wing’ – lived in the Late Jurassic period in what is now southern Germany.
The first fossil skeleton of one of the creatures, known as the London Specimen, was unearthed in 1861 near Langenaltheim and is housed at London’s Natural History Museum.
Similar in size to a magpie, it shared characteristics of Earth-bound dinosaurs and modern birds, including winged feathers, sharp teeth, three fingers with claws, and a long bony tail.
However despite being thought of as the first bird, experts now view Archeopteryx as a flying dinosaur. Nor was it a direct ancestor of modern birds.
Despite sharing a common dinosaur ancestor with birds, Archaeopteryx represents a ‘dead end’ side branch on the evolutionary tree.
Present day birds are generally believed to have evolved from a group of small meat-eating dinosaurs known as maniraptoran theropods.
The full findings of the study were published in the journal Nature Communications.