'Amazing dragon' fossils rewrite history of long-necked dinosaurs

Fossils unearthed on ahillside in northwestern China are forcing scientists to rethinkthe history of a dinosaur lineage that produced the largestanimals ever to walk the planet.

Scientists on Tuesday announced the discovery of Lingwulongshenqi, an early member of the well-known group of plant-eatingdinosaurs called sauropods with long necks, long tails, smallheads and pillar-like legs. Lingwulong lived 174 million yearsago during the Jurassic Period.

Its name means "amazing dragon from Lingwu," the closestcity to the site where a farmer spotted the fossils whileherding sheep.

The scientists excavated bones from at least eight to 10Lingwulong individuals, the largest of which was about 17.5 metres (57 feet)long, said paleontologist Xing Xu of the ChineseAcademy of Sciences, who led the study published in the journalNature Communications.

Lingwulong represents the earliest-known advanced member ofthe sauropod lineage, as defined by anatomical traits thatdistinguish them from primitive sauropods that first appearedtens of millions of years earlier.

The discovery pushes back by 15 million years the appearanceof advanced sauropods, a lineage that later would includeJurassic giants like Diplodocus and Brontosaurus as well asCretaceous Period behemoths like Argentinosaurus, Dreadnoughtusand Patagotitan that were the largest land animals on record.

"Previously, we thought all of these advanced sauropodsoriginated around 160 million years ago and rapidly diversifiedand spread across the planet in a time window perhaps as shortas 5 million years," said University College Londonpaleontologist Paul Upchurch, a study co-author.

"However, the discovery of Lingwulong means that thishypothesis is incorrect and we now have to work with the ideathat, actually, this group and its major constituentlineages originated somewhat earlier and more gradually,"Upchurch said.

Lingwulong lived in a warm and wet environment with lushvegetation including conifers, ferns and other plants. Its neckwas not as long as some other sauropods, and it may have grazedon low, soft plants with its peg-like teeth. Because so manyindividuals were found together, the researchers suspectLingwulong, like other sauropods, lived in herds.

Lingwulong belonged to a sauropod subgroup that previouslywas thought to have been absent from East Asia because itevolved after that land mass split from the rest of Pangaea, anancient supercontinent.

"Our discoveries indicate that eastern Asia was stillconnected to other continents at the time," Xu said.