Hold a bird field guide and flip quickly through your pages – so fast that you can feel an air against your face. As soon as the page slips like a cartoon in front of your eyes, the glow of colors will tell the stories of development. They usually have two basic stories. The color of the feathers of a bird tells us something about the nature of the bird’s environment or about the sexual preferences of the pickery women. Sometimes, however, there are individuals whose color does not fit any one of these schemes, and they are those whom I want to talk about today.
Many mechanisms contribute to the color of an animal, the most common have pigments. Mammals, with their relatively dull tones, rely on melanin and melanin derivatives in their skin. Birds, which are known for their dazzling colors, add carotenoids, lipocromes and porphyrin to the mixture. In addition, structural colors often interact with the pigment, further expand their visual palette.
Melanin, however, remains the original pigment for both mammals and birds. It has two forms, foamlanin (red-yellow tones) and uumlanin (brown black tones), called melanocytes produced by specialized cells. But, genetic mutation can result in the complete or partial absence of this pigment in the skin (and, more rarely, in the retina), which is called albinism or lucism, respectively.
Albino birds are completely white, and because they have a lack of melanin in the retina, as well as their eyes look pink. Less generally, some birds have to appear a luxurious yellow or patch, in which the eye color is normal, slightly lighter, or even blue, and is called luxtive coloring.
You must have focused on strangely colored birds in your area, which at first glance looked like those you see every day. It is in cities that lucistic birds can be seen more often than wild. There may be several reasons for this.
Luceism is often caused by the recurrence of genes of genes. For the characteristic to reveal, two such aliles should be found in the same body. It is like a two -dice rolling and waiting for two sixes to come up. In the small urban population, where there is no lack of inbreeding, these rare aliles are more likely to meet and cause color changes in the carrier.
Another reason is that lucistic birds are more common in cities, at least prediction pressure, especially such as hooks from avian predators. Urban areas can serve as relatively safe haven for birds whose distinctive plumage will otherwise make them an easy goal in the wild.
Unusual plumage dyeing can cause another major problem for a person. Although it cannot always affect their existence opportunities, it can have a dramatic effect on their reproductive success. Women of many birds are infamous and are obsessed with plumage patterns and colors. A lucistic man can be a bad joke for them. Fortunately, there are tolerant samari that will give these strange a chance, as some studies have shown.
Melanin in the wings also fulfills the objectives beyond the aesthetics. It acts as a structural reinforcement within the keratin matrix of the wings. Note how otherwise pure white galls have black feathers? Without melanin, wings wear more quickly, potentially compromise flying efficiency, increase energy expenditure, and once again increase the risk of prediction.
Then in 1833 is the first seen incident by the German Zoologist Constantine Wilhem Lambert Glogar. He observed that mammals and birds living in moist areas are stored more heavier than their counterparts in dryer, cooler climate. In addition to the important role of melanin in UV protection, it turns out that melanin-rich feathers and fur are more resistant to erosion of bacteria-some is particularly useful in equatorial regions where microbes thrive.
In the previous article, I discussed Structural colorBirds one of the relatively common sources of vibrancy. This time I focused on the opposite event: genetic mutation resulted in complete or partial loss of color. Both albinism and luxium are relatively rare in nature, showing such an animal a special phenomenon. If you have ever been lucky that they are enough to hold a wild leukistic or even a picture of the Albino bird, then I would prefer to share it with you. I would be happy to include your image in the update of this article.
