PARIS, Nov 1 ― Birds have more in common with dinosaurs than previously thought as new research showed yesterday they inherited coloured eggs directly from their scaly ancestors.

The evolutionary link between dinosaurs and birds has been recognised for centuries but ornithologists long believed that birds evolved their coloured eggs several times over history, mimicking local hues to help their eggs blend in.

Birds are the only creatures known today to lay coloured eggs, and do so using only two pigments ― red and blue.

Researchers analysed 18 fossil samples of dinosaur eggshells in the US, Taiwan and Switzerland, using lasers to test for presence of the same pigments.

They found them in eggs from dinosaurs including Velociraptor, which lived in the region of what is now Mongolia around 75 million years ago.

"This completely changes our understanding of how egg colours evolved,” said Yale University palaeontologist and lead study author Jasmina Wiemann.

She said her team believes the dinosaurs evolved egg colour to protect their offspring from predators when they started building open nests, a trait passed on to birds, which nearly always leave their eggs exposed before hatching.

"Colour eggs have been considered a unique bird characteristic for over a century,” said Mark Norell, the Macauly Curator of Palaeontology at the American Museum of Natural History.

"Like feathers and wishbones, we now know that egg colour evolved in their dinosaur predecessors long before birds appeared.”

The study was published in the journal Nature. ― AFP