The fossil remains of a feathered dinosaur as big as a school bus were recently discovered in China, according to an account in the journal Nature. The discovery challenges some common assumptions about dinosaurs, even giving credence to theories that some of the larger ones may have been warm-blooded.
The newly-discovered little brother to the Tyrannosaurus rex was named the Yutyrannus huali, which translates in Mandarin and Latin to "beautiful feathered tyrant."
Macalester College paleontologist Kristi Curry Rogers told Steven John of All Things Considered on Thursday that the estimated 3,000 pounder is the largest dinosaur to be found with well-preserved feathers.
"Paleontologists have known for about 20 years that dinosaurs were closely related to birds, the meat-eating dinosaurs gave birds their specialized feathers," she said. "We've always found [feathers] in small animals before, this is exciting."
It doesn't appear that the feathers would help the dinosaurs soar, Rogers said. But the six-inch long quills might have served another purpose.
"We can not necessarily rule out things like sexual dimorphism...and we can't rule out insulation," Rogers said. "Most of the time, these kinds of interesting biological structures have more than one function for organisms, they don't do just one thing."
If insulation was part of the equation, it could mean that some large dinosaurs were warm-blooded, just like people.
"The only animals on earth today that have insulation, like hair and feathers, are warm-blooded," she said. "This is one of the extra pieces of information that points toward warm-blooded dinosaurs."
As with much in paleontology, it's just a hypothesis that some dinosaurs, perhaps even the T. rex, could have been warm-blooded.
"There's no solid fossil argument of feathers in T. rex ...but because it's a close relative of T. rex, I don't think it's completely out of hand to imagine that T.rex might have had some feathers on its body," Rogers said. "I think that already people have begun to sort of renovate their imaginative views of Tyrannosaurus rex as having feathers."