Like the Wright Brothers, evolution didn't get flight exactly right the first time. It takes experimentation to find the best design, and now palaeontologists have found one of nature's quirky side projects – a strange dinosaur that was covered in feathers but had leathery bat-like wings.

Dated to about 163 million years ago, the creature is called Ambopteryx longibrachium, and it looks like a weird cross between a bird, a bat and a therapod dinosaur. It was tiny, measuring just 32 cm (13 in) from nose to tail, and tipping the scales at a petite 200 g (0.4 lb).

Ambopteryx is the latest species found to belong to a dinosaur group known as scansoriopterygids. This family is related to other early fliers like Archaeopteryx and Anchiornis, but it uses a very different mechanism – where those animals had feathery bird-like wings, Ambopteryx's wings were made up of membranes stretched out over long, thin fingers.

Ambopteryx longibrachium looked like a strange cross between a bird, a bat and a therapod dinosaur Min Wang

That style of wing arose earlier in pterosaurs (although there's evidence that they also might have been covered in feathers) and was later honed in mammals like bats. But in the case of Ambopteryx, it appears to have been an evolutionary dead end, which is why a bat-winged, feathered therapod seems weird to us now. The other feathered flying dinosaurs, meanwhile, were extremely successful, eventually giving rise to modern day birds.

The team says that this kind of wing structure most likely arose soon after the scansoriopterygids branched off from the bird lineages. Ambopteryx isn't the only known animal in this family to have batty wings, either – a creature named Yi qi, discovered in 2015, was the first found with the trait. While the two are very closely related, the team found enough biological differences to call Ambopteryx a new species.

Ambopteryx is a fascinating creature, not least because it's like looking back on Da Vinci's flying machines – an elegant but ultimately unsuccessful early experiment with flight.

The research was published in the journal Nature.

Source: Chinese Academy of Sciences