Changes

==Introduction==

==Introduction==

Vocalisation is an important evolutionary ability of birds. The extend of song varies in different avian species from complex pitches, patterns and rhythms in songbirds to the amusing squawk of penguins. Birds lack vocal folds and so sound is produced in the syrinx.

Vocalisation is an important evolutionary ability of birds. The extend of song varies in different avian species from complex pitches, patterns and rhythms in songbirds to the amusing squawk of penguins. Birds lack vocal folds so sound is produced in the syrinx which is the avian equivalent of the mammalian vocal cords.

[[Image:Syrinx Anatomy.jpg|thumb|right|150px|Anatomy of the Syrinx - Copyright RVC]]

[[Image:Syrinx Anatomy.jpg|thumb|right|150px|Anatomy of the Syrinx - Copyright RVC]]

==Structure==

==Structure==