Sometimes, when I see birds, I imagine what it’s like to be them, to fly in the vast sky, chirp sweet music and see the world from hundreds of feet above. Imagining this gives me a thrill of adrenaline like I can do anything. It gives me a sense of power, control and most of all, freedom.
When we think of flying animals, our minds probably go immediately to birds. Birds’ anatomy is designed so they are able to fly effortlessly. This is due to evolution over millions of years. Different factors such as environment, prey and predator caused different variations in the way birds are built.
To fly, birds need their wings. Wings are made up of three limb bones: The humerus, the ulna and the radius. These limb bones are called “digits.” Dinosaurs are thought to be the ancestors of birds and they had five digits, but birds only have three. There are many theories on why this is.
One says the digits shifted position and only the middle three remained. The three digits birds have are used to help with anchoring. Wings have feathers and strong muscles attached to the digits. Their strong muscles (in the chest and the wings) help them flap their wings and fly. Birds are also very light and have thin, hollow bones.
Many of their bones are naturally fused together; for example, their finger and wrist bones. Their pelvis is also fused. This decreases their mass. Being light, having hollow bones and having a small mass are important to enabling birds to fly.
When birds flap their wings, the clavicle, also known as the wishbone, (this bone can also be found in humans) helps them pump their wings and also assists in moving air to the lungs. The clavicle is near the shoulders of birds. Birds’ leg bones are heavy, which does two things: It lowers their center of gravity, which makes it easier to fly, and helps with the quick landings they must make in order to escape their attackers.
Birds’ wings are shaped in a way that causes the airflow to hit above and below the wings, causing a high pressure below the wings and a low pressure above the wings. This is called an airfoil shape. This shape helps with creating the lift birds need to fly higher. Birds use their tails to turn when they fly and when they want to land, they spread out their wings and stretch their feet.
Birds’ wings also use two pairs of large muscles that move the wings while they are in flight. These two muscles are called the pectoralis and the supracoracoideus. The pectoralis lowers the wing, while the supracoracoideus raises it. These two muscles cause the wings to flap up and down over and over. They also make up 30% of a bird’s mass.
Birds’ eyes have short optic nerves that are made up of numerous amounts of receptors. This helps in reacting to stimuli faster. Their eyelids also help wipe away the dust particles they might encounter while flying.
Since birds fly for a long amount of time, their lungs are different from those of humans. They don’t expand or contract (ours do) and are made up of nine air sacs (we have 600 million). Their air also travels in the same direction, which enables them to take in oxygen even while they’re exhaling. We breathe in and breathe out, hence, our air travels in two directions.
The way birds are built has inspired engineers to construct airplanes in a way that imitates them. This is why our airplanes are so effective and efficient.
Vaageesha Das is a rising 10th grader at Morgantown High School. Today’s information comes from: https://en.wikipedia.org/wiki/
Bird_flight; https://www.youtube.com/
watch?v=YhWbKvR_GBA; https://study.com/academy/
lesson/how-do-birds-fly-lesson-for-kids.html; https://natureecoevocommunity.
nature.com/users/264836-thomas-adam-stewart/posts/51346-the-evolution-of-digits-and-the-origin-of-the-bird-wing; http://people.eku.edu/ritchi
song/birdrespiration.html; http://microbemagic.ucc.ie/
explore_body/air_sacs.html
