The most comprehensive picture yet of how dinosaurs evolved millions of years ago has been produced, say scientists.

A team from Bristol University has spent more than two years researching the "evolutionary supertree" of the ancient species.

Aided by a computer programme, researchers put several smaller evolutionary trees together to produce links between 277 species.

They say this could be the most detailed insight into any species ever created.

Dinosaur evolution

The findings will be reported in the Proceedings of the Royal Society in the first week of May.

Professor Mike Benton, head of the Department of Earth Sciences said: "It's not complete, but it's the most detailed and comprehensive single evolutionary tree produced for dinosaurs.

"We hope the supertree will represent a solid framework for future study of dinosaur evolution.

"We would like it to stimulate and direct further studies towards the less well understood areas of dinosaur classification that are highlighted as branches in the supertree."

More than 1,000 species of dinosaurs have been discovered since the first skeletons were found in the 19th century.

Unravelling their patterns of evolution has been a major area of research.

Since 1980, more than 150 evolutionary trees of dinosaurs have been published, most of them looking at small species groups.