Scientists discover feathered dinosaur provides more clues to evolution of birds

A creature that looks like a cross between a chicken and a dinosaur is helping paleontologists better understand the link between dinosaurs and modern-day birds.

There's a scientific consensus that birds are descended from dinosaurs, but exactly how their feathers developed and when they began to take flight isn't yet understood.

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Now, a team of scientists from Canada and China hasdiscovered a new species of feathered troodontid dinosaur, theJianianhualong tengi,believed to have lived about 125 million years ago.Troodontidsare believed to be the closest relative to birds.

"Troodontidsare interesting because we need to understand their evolution history if we're to fully understand how birds evolved, how their flight evolved,"saidMichael Pittman,from the University of Hong Kongand co-author of the paper published in Natureon Tuesday.

Ithink there are a lot of surprises out there yet for us.- Phillip Currie, paleontologist

Though the feathers are asymmetrical, the researchers don't believe JianianhualongTengi flew. Instead, it may have used its feathers in other ways, such as as a sexual display orto warm eggs in nests. The feathers also gave it an aerodynamic advantage, perhaps allowing it to quickly flee from predators.

The fossil was discoveredin northeastern China four years ago. Just as the Alberta's Badlandsis known in Canadafor its rich dinosaur fossils, China is a hotbed of incredibly well-preserved fossils.

More to be discovered

While there are still some missing gaps, the researchers said they're moving forward to fill them in.

"In a way this gives us some answers and some clues, and in other ways, it says there's something else going on,"said PhilipCurrie, a paleontologist at the University of Alberta and another author of the paper.

"It's not a black and white thing where asymmetrical feathersindicated they were flying animals, and symmetrical feathers indicated they're not flying animals. It's not that simple. It's a cautionary tale in part, and it's also one more piece in the puzzle."

The researchers also found it interesting that JianianhualongTengishowed something called mosaic evolution, whereby parts of the bodies evolve without simultaneously affecting other parts. For example, itsforelimbs resembled those of early troodontids, but its legs resembledlater troodontids.

The research serves as a reminder that there are far more species of dinosaurs waiting to be discovered.

"For a long time,we thought we knew a lot of dinosaurs, but we don't," Currie said.

"I don't think we've discovered more than one per cent of one per cent of the dinosaur speciesthat lived," he said. "They were incredibly diverse animals . When you think we know somewhere between 1,200 and 1,500 dinosaurs worldwide for 150 million years, we know nothing."