Birds have many fewer bones in their skeletons than humans (who have 206). This is because birds are adapted for flying and many of their bones are fused together. Many of their bones are also hollow to lighten their weigh for flying. Flightless birds do have solid bones. Unlike humans, different bird species have different numbers of bones in their skeletons.
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Amsel, Sheri. "How Many Bones are There in a Bird's Body?" Exploring Nature Educational Resource ©2005-2019. July 18, 2019
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