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| Canadian dig yields tiny dinosaur | Canadian dig yields tiny dinosaur |
| (about 9 hours later) | |
| The smallest meat-eating dinosaur yet to be found in North America has been identified from six tiny pelvic bones. | The smallest meat-eating dinosaur yet to be found in North America has been identified from six tiny pelvic bones. |
| Hesperonychus was the size of a small chicken, and used its rows of serrated teeth to feed on insects, experts say. | |
| The bird-like creature is closely related to Microraptor - a tiny feathered dinosaur discovered in China. | The bird-like creature is closely related to Microraptor - a tiny feathered dinosaur discovered in China. |
| The specimen helps to confirm that reptiles, and not mammals, filled the role of small predators during the age of the dinosaurs. | The specimen helps to confirm that reptiles, and not mammals, filled the role of small predators during the age of the dinosaurs. |
| The fossil skeleton, which lay misidentified for 25 years as a lizard, belongs to a group of dinosaurs called the theropods - bipedal reptiles that eventually gave rise to birds. | The fossil skeleton, which lay misidentified for 25 years as a lizard, belongs to a group of dinosaurs called the theropods - bipedal reptiles that eventually gave rise to birds. |
| "Despite the discovery of exquisitely preserved skeletons of small bird-like dinosaurs in Asia, they are exceedingly rare in North America," explained Dr Philip Currie, a palaeontologist from the University of Calgary and co-author on the paper. | "Despite the discovery of exquisitely preserved skeletons of small bird-like dinosaurs in Asia, they are exceedingly rare in North America," explained Dr Philip Currie, a palaeontologist from the University of Calgary and co-author on the paper. |
| Dr Currie had been pondering why so few small fossils have been unearthed in Alberta, Canada - one of the world's richest sites for large-dinosaur bones. | Dr Currie had been pondering why so few small fossils have been unearthed in Alberta, Canada - one of the world's richest sites for large-dinosaur bones. |
| He suspected that small dinosaurs did not preserve well in the region of the prevalence of larger predators in the area. | He suspected that small dinosaurs did not preserve well in the region of the prevalence of larger predators in the area. |
| "There were many large dinosaurs running around eating them, and small bones are easily washed away by rivers [common in this region during the Cretaceous period]", Dr Currie said. | "There were many large dinosaurs running around eating them, and small bones are easily washed away by rivers [common in this region during the Cretaceous period]", Dr Currie said. |
| The new find casts more doubt on whether mammals would have acted as small predators in Cretaceous-era North America. The fossilised pelvis came from an animal that weighed no more than 1.9kg (4.2lb) and appears distinctively reptilian. | The new find casts more doubt on whether mammals would have acted as small predators in Cretaceous-era North America. The fossilised pelvis came from an animal that weighed no more than 1.9kg (4.2lb) and appears distinctively reptilian. |
| "This tells us that [as in Asia], North American dinosaurs likely out-competed mammals for both large and small predator niches," Dr Currie told BBC News. | "This tells us that [as in Asia], North American dinosaurs likely out-competed mammals for both large and small predator niches," Dr Currie told BBC News. |
| 'Tree-hugging raptor' | 'Tree-hugging raptor' |
| The authors also suggest this discovery helps to resolve debate over whether flight originated from animals that ran on the ground, flapping their arms, or whether it started with tree-climbing animals gliding downwards. | The authors also suggest this discovery helps to resolve debate over whether flight originated from animals that ran on the ground, flapping their arms, or whether it started with tree-climbing animals gliding downwards. |
| Based on the size of the hips, and because one of the hip bones was bent - the pubis, a small bone that sits between the legs - "we know this dinosaur was a tree-climber", Dr Currie explained. | Based on the size of the hips, and because one of the hip bones was bent - the pubis, a small bone that sits between the legs - "we know this dinosaur was a tree-climber", Dr Currie explained. |
| "It likely used the long feathers on its limbs to glide or parachute from tree to tree." | "It likely used the long feathers on its limbs to glide or parachute from tree to tree." |
| The specimen, Hesperonychus elizabethae - named after its collector Dr Elizabeth Nicholls - was reclassified by palaeontolgist Dr Nicholas Longrich, a co-author of the paper, from the University of Alberta. | The specimen, Hesperonychus elizabethae - named after its collector Dr Elizabeth Nicholls - was reclassified by palaeontolgist Dr Nicholas Longrich, a co-author of the paper, from the University of Alberta. |
| The findings were reported in a recent article in the journal Proceedings of National Academy of Sciences. | The findings were reported in a recent article in the journal Proceedings of National Academy of Sciences. |