The research, described in the journal Science, indicates that birds and dinosaurs perch on the same branch of the evolutionary tree.

"With what we have, the bird is the winner," said study author John Asara, a researcher at Harvard Medical School and Beth Israel Deaconess Medical Center.

"It looks like chicken might be the closest among all species present in today's databases."

The theory of a bird-dinosaur connection has been around for several years. The researchers say this work boosts that theory.

Asara and colleagues analyzed protein fragments from a

68-million-year-old T. rex femur found in the face of a cliff in Montana.

Their research showed that the dinosaur protein also resembles that of newts and frogs, although less than that of the chicken.

Their work would warm Charles Darwin's heart.

"It's a wonderful prediction of evolution," said Larry Witmer, an anatomist and dinosaur expert at Ohio University.

"As you go back in time, animals tend to be more and more similar, and that's exactly what we're seeing,"

T. rex, however, probably didn't sport feathers, he said.

Although the Science research evokes Jurassic Park, Witmer said he doesn't see science catching up with science fiction anytime soon.

Sequencing proteins eventually could reveal clues about T. rex genetics and provide another way to make evolutionary connections between living animals and those that have long been extinct.

mlafferty@dispatch.com