Written By: Sarah Girton
One of the most identifying features of birds, the feather is a hallmark of evolutionary specialization. These highly-versatile plumes aid birds in flight, keeping warm, attracting mates, and warding off predators.
Science of the Feather
Interestingly, the molecular structure of the feather allows it to be an even tougher keratin material than hooves! Most birds possess two main types of feathers: Contour feathers, which aid in flight and visual display, and down feathers, which aid in trapping body heat, as well as maintaining buoyancy in water birds. The difference between these feathers stems mostly from the presence or absence of barbules, which hook the individual barbs of the feather together. They function much the same as a zipper and allow for maximum air resistance when flying.
Just as mammals shed their fur, a bird’s feathers must be replaced on a regular basis through the process of molting. From weather, regular use, and getting into scuffles, feathers can wear down, lose their luster, and barbules can break. Once the nesting season has ended, a bird can begin the molting process. Unless the bird is sick, they will only lose a few feathers at a time so that they can still fly and keep warm.
Feather uses in birds
We’ve talked about the science behind how feathers work, but how do birds use them? If you’ve ever seen a peacock in his mating display, then you already know one of the answers! The variety in colors, shapes, and patterns of a bird’s feathers are one reason people love birds so much. The entire color spectrum is represented in these soft and fluffy plumes. Bird families like Thraupidae – the tanagers, or Phasianidae – pheasants and peafowl, use their colorful and ornate plumage to attract mates.
Of course, one of the main purposes of the feather is to aid in flight. There are three main types of bird flight: Gliding, flapping, and bounding. With gliding, birds use upward air currents called thermals. Many species of seabirds use this method since it requires the least amount of physical exertion, as many of them only return to land in order to breed and raise young. Flapping flight is a steady motion of flapping wings in order to stay level. This type of flight provides a constant lift while also causing a forward thrust. And bounding flight is used by a lot of smaller birds. With a short, sporadic burst of wing beats, a bird can gain some serious forward motion and then fold its wings against its body to shoot forward like a little torpedo.
Some birds also use feathers to ward off threats. They will poof out their feathers to look larger, and it works like a charm! Owls are one of the bird families that are known to use this tactic.
We hope you’ve enjoyed our posts about feathers this week! They really are amazing!