Find out: 1  the documents you need. 2  the common errors to watch for. 3  the consequences of filing an EITC return with an error. 4  how to get help preparing your return. 5  what you need to do if your EITC was denied in a previous year. 6  how to claim the credit for earlier tax years.
Biological pigment. The budgerigar gets its yellow color from a psittacofulvin pigment and its green color from a combination of the same yellow pigment and blue structural color. The blue and white bird in the background lacks the yellow pigment. The dark markings on both birds are due to the black pigment eumelanin.
Mixtures of pigments can also produce different and unusual color hues and shades. For example, the dull olive-green colors of certain forest birds is actually a mixture of yellow carotenoid pigments and dark-brown melanin pigments. Then we get to the second main ingredient that produces color: keratin. Keratin is the tough protein of which feathers are made. It also covers birdsâ bills, feet and legs. Keratin is responsible for the iridescent coloring of many spectacular bird species.