Their colors have long been a subject of speculation among researchers and schoolchildren.
In the new study, reported in Thursday's online edition of the journal Science, scientists focused on melanosomes, which impart color.
They were able to assign color to individual feathers and thus work out color patterns for the entire fossil of Anchiornis huxleyi, a small, feathered, two-legged dinosaur that lived roughly 150 million years ago.
The animal would have weighed about four ounces (110 grams) and appears to have had a dark gray or black body and wings with some white feathers that gave it a stripe pattern, plus a reddish-brown crest and speckles on the face.
"This was no crow or sparrow, but a creature with a very notable plumage," said Richard O. Prum, professor of ornithology at Yale University and a co-author of the study.
"This would be a very striking animal if it was alive today," Prum said in a statement.
The specimen they studied was found in China, which was also the home 125 million years ago of Sinosauropteryx, a creature that seems to have had russet-colored feathers, according to a paper published last week in the journal Nature.
Prum speculated that the color pattern of A. huxleyi could have served as a signal to attract mates.
Co-author Julia Clarke, an associate professor of paleontology at the University of Texas at Austin, suggested that color patterns for camouflage or display must have had a key role in the early evolution of feathers in dinosaurs.
The research was funded by the National Science Foundation, University of Akron, the National Geographic Society and Yale University.
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