Birds are known for their vibrant and striking plumage, but what if we told you that there is more to their colors than meets the eye? A recent study by Rosalyn Price-Waldman and her colleagues at Princeton University has uncovered a fascinating secret behind the colorful feathers of tanagers, a type of songbird.
Tanagers, like the green-headed tanagers (Tangara seledon) featured in the study, exhibit bright red, yellow, and blue plumage that catches the eye. What Price-Waldman and her team discovered is that beneath these dazzling colors lies a hidden layer of either black or white feathers. This hidden layer acts as a primer, much like how painters use a white base to enhance the colors on their canvas.
To investigate this phenomenon, the researchers carefully examined 72 feathers from tanagers in museum collections. They found that the underlayers of feathers play a crucial role in enhancing the colors of the top layers. For red and yellow plumage, which are created by pigments that absorb light, the white layer underneath reflects light back, making the colors appear brighter. On the other hand, blue plumage, which is created by nanostructures that scatter light, benefits from a black layer below that intensifies the blue hue.
The researchers also discovered that these hidden layers of feathers contribute to the differences in coloration between male and female tanagers. In some cases, females have black underlayers beneath yellow feathers, while males have white underlayers. When placed on different backgrounds, these subtle differences in underlayer color become more apparent.
This color-boosting strategy is not unique to tanagers but is also observed in other songbirds like manakins and cotingas. Chris Cooney from the University of Sheffield notes that this mechanism of enhancing plumage colors may be more widespread across bird species than previously thought.
In conclusion, the study sheds light on the intricate ways in which birds use hidden layers of feathers to enhance their colorful appearance. It highlights the complexity of bird coloration and opens up new avenues for research into the evolution of vibrant plumage in avian species. The next time you admire a tanager’s bright feathers, remember that there is more than meets the eye to their stunning beauty.