Dinosaur with brains and maternal instinct

Could the 80-million-year-old "egg thief" found beneath the sands of the Gobi Desert, and from Sunday on display at the Natural History Museum in London, be the most intelligent of all dinosaurs and the forebear of birds?

The Mongolian palaeontologist Dr Rinchen Barsbold has stuck his neck out with the theory that the 2-metre-long Oviraptor is indeed the link with birds and could have been warm-blooded. But most of his professional counterparts are more cautious.

Dr Angela Milner, the museum's head of fossil vertebrates, is excited at being able to display the "Dinosaurs of the Gobi Desert", including a 15-metre-long cousin of Tyrannosaurus Rex, in Britain for the first time but emphasises the conditional on Dr Barsbold's claims.

In the carefully weighed words of the museum: "This is a highly controversial theory in the palaeontological world as the evidence is not conclusive and in some areas cannot be substantiated."

If the combination of exotic Central Asian locations and characters, fossils of ferocious beasts and the measured language of science smacks of the film script, it is not surprising.

The first important discoveries in the Gobi, the richest dinosaur graveyard in the world, were by the American Roy Chapman Andrews who served as a model for the whip-wielding antiquities hunter, Indiana Jones. Set against a desert backdrop, the display at the museum ranges from the giant meat- eating Tarbosaurus, or "alarming lizard", to the delicate Psittacosaurus, or "parrot lizard", the smallest plant-eating dinosaur ever discovered.

The violent sand storms which have battered expeditions to the Gobi Desert have also provided perfect conditions for preserving whole skeletons.

Oviraptors were discovered by Chapman Andrews close by eggs which were thought to be those of Protoceratops, the most commonly-found dinosaur in the Gobi. Living 85-80 million years ago, Oviraptor had a powerful toothless beak and huge hands capable of grasping prey.

But its name, meaning "egg thief", was proved false in 1993 with the discovery of an egg containing an Oviraptor embryo and a fossil nest with a skeleton crouching over it, as if protecting the eggs or incubating them when a fatal storm struck. Two other "nesting" fossils have been found.

If as Dr Barsbold's believes, "big mamma" oviraptor was incubating the 22 eggs, it strengthens his case that the creature was warm-blooded. Oviraptor's brain size was also large relative to its body.

Dr Barsbold, director of the Geological Institute of the Mongolian Academy of Sciences, explained that in Ulaanbataar he has a close relative of the Oviraptor, called an Ingenia, which though only 1.5m long and weighing 50-60 kilos had a brain the size of the Tarbosaurus which weighed perhaps 3,000 kilos.

"What does this mean?" he asked. "I think the higher level of intelligence and the very characteristic pose of the Oviraptor sitting on the nest with the air of incubation means it could be a warm-blooded animal, as birds like the eagle and vulture which are also carnivorous."

The Dinosaurs of the Gobi exhibition, which is supported by the Discovery Channel, can be seen at the Natural History Museum, South Kensington, London, from 18 May to 31 August.