Question

The carotenoids on a yellow birds feathers absorb all light frequencies except for
A. Yellow
B. Green
C. Red
D. White
E. Blue

Answer 1

Hint: Dark colors absorb a lot more heat than lighter colors because they absorb more light energy. The colors in the feathers of a bird occur in two different ways. They are either from their pigments or from the light refraction.

Complete Answer:
Carotenoids are an important factor in the plumage of birds. Plum age patterns are important in communication among birds. Oranges, reds, and bright yellows are mostly xanthophylls, keto, and hydroxy carotenes. Early workers demonstrated that carotenoids are derived from the diet and deposited selectively. A subsequent investigation found that various plumage color morphs are due to simple chemical changes in carotenoids and it is important to note that many of these processes are under genetic control. Recent studies have done an assumption on genetic divergence. And also they demonstrated the synthetic changes in color.

- Spectroscopy was used to investigate the molecular and structural changes in carotenoid protein interaction which is responsible for the different coloration in plumage. Carotenoids pigments are responsible for the color of feathers and are considered to be important for communication in many bird species. Coloration in the feather is due to the scattering of light and by pigments that absorb light in specific regions.

- Carotenoids give rise to orange, red, and yellow colorations. The green color in feathers is due to a combination of yellow and blue colors. Birds don’t have the ability to synthesize carotenoids in their body so it has to be ingested with their food. After ingestion, carotenoids pass to various tissues of the body and then are carried for different biological functions. Carotenoids that are incorporated during feather development bind strongly with the proteins.

- When white light is incident of an object it absorbs some essential colors of the white light and some are reflected. The combination of the colors reflected decide the color of an object that we could see. Carotenoids are pale yellow and it absorbs constituent colors of white light and reflects only yellow color. That is it does not absorb the yellow frequency.

Thus the correct option is A, ‘Yellow’.

Note: The most common carotenoids in the diets of most birds are lutein, zeaxanthin, β-carotene, and β- cryptoxanthin. Some birds convert these dietary pigments into yellow canary xanthophylls or red keto carotenoids that they deposit into feathers or bare parts.