Adaptation is the evolutionary process where an organism becomes better suited to its habitat. This process takes place over many generations. It is one of the basic phenomena of biology.
When people speak about adaptation, they often mean a 'feature' (a trait) which helps an animal or plant survive. An example is the adaptation of horses' teeth to grinding grass. Grass is their usual food; it wears the teeth down, but horses' teeth continue to grow during life. Horses also have adapted to run fast, which helps them to escape their predators, such as lions. These features are the product of the process of adaptation.
Bird beaks show an obvious sign of their different ways of life. However, eating a different food also means having a different digestive system, gut, claws, wings and above all, different inherited behaviour. For the major adaptations, what changes is not a single trait, but a whole group of features.

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