TRANSCRIPT:
London's Natural History Museum is home to some 80 million natural specimens - and now, it has is one more.
Among the museum's impressive dinosaur collection, the skeleton of an Enigmacursor is a relatively small, but significant, new exhibit.
"So Enigmacursor is a small plant-eating dinosaur. It walked around on its hind legs, would have been quite a speedy runner. And it's a fairly rare animal from this time and from this part of the world. It comes from the Western USA, from Colorado, and it lived about 150 million years ago and would have be scuttling around the feet of more famous dinosaurs like Stegosaurus and Diplodocus."
Professor Paul Barratt is a palaeontologist at the museum, whose research helped identify this new dinosaur species.
The Enigmacursor roamed the Earth in the late Jurassic period but remained unknown until a remarkably intact skeleton was unearthed from a quarry nearly four years ago.
It was initially described as a nanosaurus, a poorly-known species first recorded in the 1870s.
Until, that is, the fossil's discovery solved a tantalising mystery.
Researcher Professor Susannah Maidment explains:
“Enigma means puzzle, of course, and this is in reference to this sort of complicated naming history of these sorts of dinosaurs. There's been up to eight or nine different names given to these fragmentary, tantalising remains and we couldn't figure it out until we found this nice more complete skeleton, so that's the enigma part. Now cursor means runner so this is in reference for the dinosaur's very long hind limbs and very big feet."
As well as powerful legs and huge feet, the Enigmacursor boasts a long swooping tail.
At just 64 centimetres tall and 180 centimetres long, it is much smaller than Jurassic giants like the 25-metre long Diplodocus.
But Professor Paul Barrett says this small creature could shed light on how its bigger cousins developed.
"This little dinosaur fills an evolutionary gap. So it is somewhere in between the origin of the big group that includes things like Stegosaurus and Triceratops and their relatives, and the development of the weird features we see in those groups. So if you like, it's the template on which those weirder, bigger dinosaurs were built. And it helps us to understand how those different features started to come into existence. And it also shows us what these late Jurassic ecosystems were like. They weren't just dominated by huge long-necked dinosaurs or huge predators, but also a cast of characters of smaller dinosaurs that are making a living in different ways."
More research is now needed to confirm whether other specimens previously thought to be nanosaurus are also different species.
Professor Sarah Maidment says it's very likely.
"It tells us that there were actually more of these small dinosaurs than we thought previously, because in our investigations in other US collections and museums, what we discovered was that there are a whole range of little fragments of bones that are different from Enigmacursor, but are from this sort of dinosaur. So we think that the diversity of these sorts of dinosaurs was greater than we previously realised."
The dinosaur's full name - Enigmacursor mollyborthwickae - credits the private donor who helped the Museum acquire the fossil.
Professor Barrett says new species of dinosaur are being found all the time, but the discovery of a skeleton such as this is rare.
"Altogether we're naming about one new dinosaur per week around the world. So about 50 to 60 new dinosaurs get a name each year. So it's not super rare to name a new dinosaur, but it's always exciting to be involved in a new discovery."
