Odd dino has rabbit-like teeth

The skull would have been about 10 cm in length

One could hardly say it was the prettiest creature ever to have walked the Earth.

Chinese scientists revealed a 128-million-year-old dinosaur on Wednesday with a large set of rabbit-like incisors. It looks very strange.

The creature, called Incisivosaurus gauthieri, belongs to the theropod class of dinosaurs, predators such as the fearsome Tyrannosaurus rex, which moved about on two legs.

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One of the more unusual dinosaurs to come out of China

Researchers from the Chinese Academy of Sciences in Beijing say this animal probably enjoyed plant food - unlike its big cousin, which liked nothing better than to rip apart and eat another beast.

The remains were unearthed in the Yixian Formation, rocks from Liaoning in northeast China that have produced a wealth of spectacular fossils, including dinosaurs with feathers.

Xing Xu, from the Institute of Vertebrate Paleontology and Paleoanthropology, and colleagues describe I. gauthieri and its teeth in the latest edition of the journal Nature.

Steak knives

They say these prominent features show theropods were more diverse than scientists had thought.

"The paired first premaxillary teeth are very similar to the incisors found in a few specialised mammalian lineages, such as rodents... which use them for gnawing, "they write.

"Incisivosaurus represents the first theropod displaying distinct dental adaptations for an herbivorous diet."

Other experts say the rodent-like teeth do not necessarily mean the dinosaur was a plant-eater, but agree the traditional view of predatory two-legged dinosaurs is changing.

Joshua Smith, from Washington University in St Louis, US, said: "The classic view of predatory dinosaur teeth is that they are all basically the same and are shaped more or less like serrated steak knives.

"However, it is becoming more and more obvious as we begin to look closely at theropod teeth that they are far more complex than we have been led to believe, and that the steak-knife view isn't accurate."