Feather grows much like our hair: a meticulously constructed mass of dead protein, called beta-keratin, pushed out from a follicle in the living skin. An analogy for feather is like a tree – its trunk, a hollow central shaft, is called a rachis, numerous branches stemmed from the rachis are called barbs, and from the barbs grow twigs called barbules. From this branching structure come two types of feathers. Downy feathers are fluffy, loosely arranged, and non-interlocking structured in order to trap air to keep warm. Pennaceous feathers are interlocking structured, stiff, flat, and smooth, forming a windproof and waterproof barrier in order to assist flight and stay dry.
From these two types of feathers derive various feather compositions to serve different functions for the bird. Wing and tail feathers are interlocking and short, with a stiff leading edge to allow for precision steering in flight. Contour feathers, which cover the body and streamline its shape, are arranged in an overlapping pattern like shingles, where the waterproof tips are exposed to the elements and the fluffy bases are tucked close to the body. Hidden beneath are semiplumes and downs, which have a fluffy insulating structure to trap heat. And then there are bristles, which are stiff and the simplest, mostly found on the head to protect the eyes and face.
When an asteroid collided into Earth 66 million years ago, causing the mass extinction of the dinosaurs, their only survivors were the birds. A fossil called Archaeopteryx with feathers, hollow bones, clawed wings, fifty tiny teeth, and a long bony tail is the earliest known dinosaur who was also a bird. The evidence of melanosomes showed that the fossil birds, as early as 150 million years ago, were colored of a dark hue with iridescent highlights, much like a modern-day starling or a blackbird. The first appearance of color pigments have been traced to a theoretical ancestor of perching birds around 50 million years ago, more than 100 million years after the solitary brown and black birds. As time has gone on, birds have progressively become more colorful, evolving into a plethora of colorful birds inhabiting the skies today.
Feather’s capacity to reflect light and their beautiful appearance in colors and forms have inspired artists the world over. Feathers were among the most valued in ancient Mesoamerica, and the most sought after were those of the resplendent quetzal, a bird found in tropical forests of Central America. Adult males grow two or three long, upper-tail, covert feathers of an emerald green color that also shades into gold or purple, depending on the angle at which they reflect light. Being up to 80 centimeters long, they are prized for their movements that arc and bend like reeds. For both the Maya and the Aztec, the quetzal was a symbol of freedom. Their long green tail feathers were seen as a link between heaven and earth. They were thus precious and luxury goods, used to make diadems for elites, rulers, and embodiments of gods, and were traded over hundreds of miles across the Mesoamerican world.
In Europe, feathers were employed as artist tools. Goose feathers were used to make drawings, to erase, to blend and smooth, as they had a unique subtlety that no other tool had. The German artist Albrecht Dürer, long fascinated by feathers, made a nature study in watercolor Wing of a Blue Roller, notable for its detailed and scientific accuracy. While traveling from Nuremberg to the Netherlands in 1520, he had the chance to view artworks, among them featherworks, brought from Mesoamerica to the court of Emperor Charles V. He wrote in his diary, “All the days of my life I have seen nothing that has rejoiced my heart so much as these things. For I saw amongst them amazing artful objects, and I marveled at the subtle ingenia of people in foreign lands. Indeed I cannot express the thoughts that came to me there.”
Of course it takes a considerable amount of time daily to maintain all these beautiful plumage. Bird preening involves drawing individual feathers through its beak, realigning and re-interlocking the barbules, cleaning plumage, and keeping parasites in check. The preen gland, located beneath the tail, produces oil that birds carefully transfer to their feathers by rubbing themselves with their bills and heads. The preening oil keeps the feathers waterproof, protects and lubricates them. Otherwise, age and exposure cause them to become brittle. Yet in all birds a feather’s autumn inevitably arrives. Much like our hair, it falls out of its follicle and the follicle begins to push out a replacement feather. Unlike our hair however, feathers are critical to the bird’s survival. Maintaining a beautiful mane takes a lot of energy, which is why, according to Charles Darwin, female birds are impressed by those who can afford lushly colorful reds and pinks when they grow new feathers.
hardlyplaying.blog 