Giant bird-lizard unearthed in China
Was it a bird, was it a plane....?
Paleontologists have unearthed a T-Rex-sized "bird dinosaur", dubbed Gigantoraptor erlianensis. The beast, which lived 65 million years ago, stood five metres tall, was eight metres long, and would have weighed in at around 1.5 tonnes.
The fossils were dug out of the Gobi desert's Erlian basin by Xing Xu, a paleontologist with Beijing's Institute of Vertebrate Paleontology and Paleoanthropology, and his colleagues.
The researchers initially thought it belonged to the same family as Tyrannosaurus Rex, but then they found its beak and realised they had something different on their hands. Pieces of bone also helped classify the beast as a member of the oviraptosauria group.
This means it belongs to the family of dinosaurs from which birds have evolved, but its massive size complicates the story of the modern sparrow's lineage.
Mark Norell, of the American Museum of Natural History in New York City, said: "Progressively from within advanced theropods you get smaller and smaller towards birds...[but] after some species originate and spring off the bird line, you get secondary gigantism."
Xu told Scientific American: "It is the largest known beaked dinosaur. Big size has some advantages such as having fewer predators and more food resources that are unavailable for small animals."
Norell professed himself "flabbergasted" by its immense size. All other known examples of this family, including its ancestors, are small, have feathers, and weigh just a few pounds.
The fossils don't answer the question of whether or not the bird-like dinosaur had feathers. But Xu says it was most likely the same as other examples of its family. Norell suggests that at the very least its young would have been feathered until they were able to regulate their own body temperature.
Gigantoraptor might have eaten meat, like the similarly sized T-Rex. But its physiology is confusing. It had a herbivore's small head and long neck, but also possessed sharp talons, more common among carnivores. Its toothless beak would have been well suited for tearing into flesh, just as hawks and other hunting birds do today. ®