How does having a sharp pointed beak limit what foods a bird can eat?

The shape of a bird's beak is a clue to its main source of food. The shape of a bird's beak is designed for eating particular types of food such as: seeds, fruit, insects, nectar, fish, or small mammals. Bird beaks have adapted over time to help birds find food within their habitat which allows them to survive. The beak, bill, and/or rostrum is an external anatomical structure found mostly in birds, but also in non-avian dinosaurs and some mammals. A beak is used for eating and for preening, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young.

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