Not all birds fly, but the majority do. Flight is the most defining and distinct locomotory feature in birds, which places birds in a fascinating world of their own. Varying from species to species, each exhibits a different flight style and wing shape.
For instance, hovering is achieved by beating the wings more or less horizontally, balancing the forward thrust by a wind gust as seen in Pied Kingfishers and Augur Buzzards. Seabirds like gulls and albatrosses employ gliding. Pelicans and cranes fly in V-shaped formations, cormorants in a single file, while vultures, storks and large birds of prey use thermals to soar in the sky.
But how do they beat all the odds to do this? Different forces act on a bird’s body enable it to fly up and remain airborne. These forces include gravity, lift, drag and thrust.
Gravity keeps us on the ground. It is the force that pushes down on the bird and is the first force that a bird in flight interacts with during take-off. To overcome it, birds create lift and thrust by flapping their wings, making air flow over and under them.
Birds have evolved over the years to adapt to flight. For starters, they have thin, hollow bones. They have no teeth, so no heavy jaws. Birds have light but strong feathers. They lay eggs rather than give birth to live young. Birds have rapid and efficient digestion. Their overlapping feathers give them a perfect streamlined body shape needed for flight.
These beautiful creatures have managed to conquer the gap of distances and explore the aerial spaces with ease, having confidence in their wings and feathers. Amazing!