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- Whydohummingbirdsandgorillasbothhavebackbones?EitheroftwoSouthAmericanhummingbirds(Topazapyraora)havingcolorfulplumage.Butthoughtseludedher,dartinginandoutofhermindlikefrightenedhummingbirds.Mostbirdsflaptheirwingsupanddown,buthummingbirdsmovetheirwi...
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