It's a complex biological operation, but hormonal changes and dietary impacts yield the results. Physically, birds need significant energy to produce bright bill colors.

My grandmother reveled at the sight of bright yellow birds with black caps that attended the zinnias in her garden each summer. Wild canaries, she called them.

Birds are some of the brightest and most colorful animals on Earth. The blues, reds, greens, purples and yellows of the avian world are rivaled, among vertebrates, only by the brilliant colors and ...

Fresh from spending the winter in Mexico, Wilson’s warblers are already beginning to appear in Orange County, making a brightly colored, energetic spectacle as they dance about shrubs in sear… ...

Plumage and body parts of birds-of-paradise glow in certain areas when viewed under blue and ultraviolet, or UV, light, appearing bright green or yellow-green, scientists reported in a new study ...

The birds-of-paradise evolved optimal brilliance to communicate something, and that something is their own attractiveness: Like so many of their striking features, biofluorescence seems to help them ...

The reasons and methods of this color communication vary massively among species and environments. Birds tend to acquire colored pigments — like red, orange and yellow carotenoids ... Little Mysteries ...

And it wasn’t until around 400 million years later that bright colors expanded across vertebrates and arthropods (a group of invertebrates with an exoskeleton, such as insects and spiders).