The history of penguins isn’t simply black & white*. In fact, ancient penguins were actually closer to reddish-brown and grey.
How do we know this? Because melanosomes—mini-organs that actually do the work of making pigment inside of melanocyte cells—can survive for millions of years as part of a fossil. A little mind-blowing, isn’t it? This is a fairly recent discovery. Up until 2008, scientists thought melanosomes perished along with other soft tissues. Since then, they’ve used hardy fossil melanocytes to figure out the color of various dinosaurs and early birds, including the ancestors of penguins.
What’s the benefit of shifting from red/grey to black/white? The color change makes more sense once you know that penguins weren’t always strong swimmers. Based on that, Stephanie at Science isn’t Fiction speculates that the tuxedo look was an adaptation that gave penguins an advantage as they took to the seas.
The darker coloration occurs with higher concentrations of melanin which may also increase the strength and rigidity of penguin’s wings. It appears as though having more melanin is at least one of the adaptations allowing penguins to become the skilled swimmers they are.
However, one expert wonders why penguins aren’t completely black if melanin is such an advantage. Another says that the black on white coloration provides camouflage. Perhaps this coloration gives penguins the “best of both worlds” so-to-speak; they have the strength of melanin as well as a white underbelly that is less distinguishable to predators in the depths.
Thanks Bora Z!
*ba-Dum-CHING. I’ll be here all week, folks.
Image: Stan Shebs, via CC
