The discovery of collagen in ancient fossils by researchers could prove to be a major breakthrough in exploring an evolutionary link between dinosaurs and birds.

The study, published in Friday's edition of the journal Science, used the unexpected discovery of collagen in dinosaur fossils to make its link between living and extinct species.

"It's extremely surprising that you have all this organic content after all this time," John Asara, a Harvard Medical School researcher, told

By using a sophisticated technique called mass spectroscopy, Asara and his team were able to obtain genetic information from dinosaurs that had been preserved for millions of years, linking them to species that currently inhabit the planet.

It also brings to mind the sort of possibilities explored in the science fiction book and film "Jurassic Park."

"Really, most of the ideas in 'Jurassic Park' are, I think, improbable -- but I don't think I'm willing to say impossible anymore," said Dr. Philip Currie, a paleontologist based at the University of Alberta.

Researchers say the discovery helps them link dinosaurs to a much smaller animal currently walking the earth.

"We have a protein sequence that we can compare to the protein sequence of other organisms that have had their genome. It looks like chicken may be its closest relative," Asara told

"But we also found matches to newt, and also to frog. So you can really start to make this evolutionary relationship."

Scientists had believed there was a link between dinosaurs and birds, but this scientific research delivers more credence to the hypothesis.

"The door just opens up to a whole avenue of research that involves anything extinct," said Matthew T. Carrano, curator of dinosaurs at the Smithsonian's National Museum of Natural History.

Researchers came to their conclusions after testing the 68 million-year-old femur of a Tyrannosaurus rex, which they suspected contained internal soft tissues including blood vessels within its bone. Their analysis revealed the presence of collagen 1, the main organic component of bone.

Collagen is a type of fibrous connective tissue and is an abundant protein in the bone of all types of animals.

"It's always been assumed that preservation does not extend to the cellular or molecular level," said Mary Higby Schweitzer of North Carolina State University, who recovered soft tissue from the bone.

The lack of water and light and microbes that could degrade bone rapidly in the arid Hell Creek formation in Montana, where the femur was found, is thought to have been a factor in preserving the protein.

Further analysis of the Tyrannosaurus rex femur, along with various bones of a mastodon which were between 160,000 and 600,000 years old, was undertaken by Asara and his team. Their analysis and research lead to their ability to make a link between dinosaurs and birds.

The researchers were supported by NASA, the David and Lucille Packard Foundation and the Paul F. Glenn Foundation in their work, and will continue to explore the links between living and extinct species.

Lewis Cantley of Harvard Medical School, a co-author of the study, is optimistic that more links will be made between living and extinct species in the future.

"Knowing how evolution occurred and how species evolved is a central question," Cantley said.

With files from The Associated Press