Birds-of-Paradise, especially males, are known for their brightly-colored and iridescent feathers. However, there are certain species that also sport some charcoal black feathers. For years, researchers have been trying to find out the secrets of this feathers that absorb the light. Also, to discover were this amazing and intense black color comes from because it’s deeper than any materials humans have created.
It’s important to know that feathers, being opaque, can get their color in two ways. Usually, the surface coatings create the wavelengths of light that an object reflects. Some examples of this would be the chlorophyll in leaves and melanin in skin. However, Dakota McCoy, the leader of the study, says that these black feathers the birds use for mating are not iridescent at all. According to the study, which Nature Communications published, the feathers absorb about 99.95% of the light. But if we were to take a closer look at the plumage, we would notice the trick.
The black feathers of the Birds-of-Paradise
The secret lays in the barbules located near the tip of the feathers: they are frayed. In comparison with them, barbules in flight feathers have some kind of small hook. McCoy says that each time light falls on them, it gets reflected into these small cavities, not outward, as it normally would.
According to experts, this study also reveals a new type of feather microstructure. The feathers are still black, but this structure does nothing more than enhance the blackness. These feathers are so special that they remained black even after being covered with a layer of gold. Normal black feathers became golden, as expected.
According to McCoy, the male Birds-of-Paradise developed these feathers to attract partners. So, when they want to mate, they make sure that the females see their feathers as black as possible. This means that the feathers are not for camouflage, as it was previously believed.
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