WASHINGTON — A 36-million-year-old fossil of a penguin from Peru shows the bird had feathers that were reddish brown and gray, unlike the black-and-white tuxedo appearance of today's penguins, researchers reported.
The new species called Inkayacu paracasensis or water king, was nearly five feet (1.5 meters) tall or about twice the size of an Emperor penguin, the largest living penguin today, the scientists reported Thursday.
"Before this fossil, we had no evidence about the feathers, colors and flipper shapes of ancient penguins. We had questions and this was our first chance to start answering them," said Julia Clarke, paleontologist at The University of Texas at Austin and lead author of a report in the journal Science.
The fossil shows the flipper and feather shapes that make penguins such powerful swimmers evolved early, but that their distinctive color patterns took longer.
"Insights into the color of extinct organisms can reveal clues to their ecology and behavior," said coauthor Jakob Vinther at Yale University.
"But most of all, I think it is simply just cool to get a look at the color of a remarkable extinct organism, such as a giant fossil penguin."
To determine the colors, the researchers studied the size and shape of melanosomes, the biological cells that produce pigments. They compared melanosomes recovered from the fossil to their extensive library of those from living birds to reconstruct the colors of the fossil penguin's feathers.