Why Are Parrots So Colorful?

Parrots are among the most colorful animals on Earth, yet scientists have struggled for decades to explain how their vibrant hues are formed. Now, a research team led by Charles University in the Czech Republic has unveiled the unique biological mechanisms behind the bright red, yellow, and green colors of these birds. Through a detailed analysis of the developmental process of parrot feathers, researchers have discovered that a simple chemical modification — a parrot-specific pigment molecule — is key, a modification that may also be crucial in other realms of the animal kingdom. The findings of this study have been published in the latest issue of Science magazine.

Distinguishing parrots from other birds, they have the ability to produce a pigment called Psittacofulvins and adjust this pigment to create red and yellow colors. Scientists have known that Psittacofulvins are composed of carbon atom chains of different lengths. The research team found that the way this chain terminates determines the color produced by Psittacofulvins. For instance, when the chain ends in an aldehyde group, feathers appear red. However, if a carboxyl group replaces the aldehyde, feathers turn yellow. Researchers highlight that this is a remarkably simple chemical adjustment.

By studying a species known as the "black parrot", which displays yellow and red hues, the research group also identified a gene crucial for coloring in these birds and their close relatives. This gene encodes an enzyme that converts aldehydes to carboxyl groups, shifting the default red pigment to yellow. The more enzymes expressed by the gene, the yellower the feathers become.