Researchers unearthed remains of a nearly 5-foot-tall penguin that roamed prehistoric Peru 36 million years ago — and its fossilized feathers imply that it was reddish-brown and gray, not starkly black and white:
Pigment is long gone in fossils. But left behind in feathers can be microscopic packets called melanosomes that in life contained color-producing pigments — and the shape of those melanosomes corresponds to different colors. So the researchers compared a library of melanosomes from living birds with these fossilized ones.
The big surprise is that it turns out modern penguins have large melanosomes packed into grape-like clusters, unlike those of any other known bird, while the extinct giant penguin’s smaller melanosomes resembled those of other birds, Clarke said.
The scientists can’t explain the difference. But they say it probably has to do with more than the black tuxedo coloration of today’s penguins.Melanin, the pigment inside melanosomes, helps feathers resist breakage. So one possibility is that the melanosomes got bigger during later penguin evolution as the birds became better underwater swimmers and needed a more hydrodynamic covering.