|MadSci Network: Zoology|
For young birds, flying involves both instinct and learning. They do not just jump out of the nest one day and fly off. In fact, they usually do not want to jump out of the nest at all (you can hardly blame them!). Their parents have to entice them to leave, for example, by flying off a little ways and calling to them. After a while, the fledglings try it, and by instinct, extend and even flap their wings as they fall. They may then spend days refining their ability to fly and learning how to handle certain situations (flying upward is of course harder than sailing down to the ground, and they may have to learn to avoid obstacles and other difficulties). Part of their improvement over time is also due to strengthening of the flight muscles (especially the pectoral, or chest, muscles).
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