Is shell circle genuine?

BEIJING - When the dinosaur eggs fetched $419,750 at auction in Los Angeles in 2006, a group of experts inspected a picture of the nest online and concluded it must have been smuggled out of China.

They reported it to the Chinese government, which sought the return of the eggs and began a five-year investigation with the help of the US authorities and the auction house.

Dinosaur expert at the Chinese Academy of Sciences, Zhao Zikui, suspects the nest was made from parts of fossil eggs taken from other nests.

"Based on the veins on the eggshells and their shape, the 22 fossil eggs are the kind commonly found in Guangdong, Jiangxi and Hunan provinces," he said.

Usually, dinosaur eggs are found in a circle with a diameter of no larger than 20 cm, he said. But with the auctioned nest, the circle is much larger.

Moreover, the larger ends of the eggs are normally arranged together, but the position of one egg in the returned nest has been reversed.

"In addition, since dinosaurs have two oviducts parallel to each other, they lay two eggs each time, and the eggs on the nest should be arranged in pairs, " Zhao said, adding that was not the case with this nest.