The hyoid apparatus or hyoid horns – are what allow woodpeckers to extend their long tongues out so far. The hyoid horns are comprised of bone and cartilage, sheathed in muscle. When the muscle contracts, the tongue is extended and hyoid horns are tight against the skull. When horns are relaxed, tongue is retracted and there is a great deal of slack.

I animated my drawing to give a rough idea of how the hyoid apparatus works, allowing the tongue to protrude and retact. Notice that the two horns grow into the right nostril. This is how it appears on an adult, the juvenile hyoid horns are not quite that long. The hyoid horns connect to the tongue around the throat area.


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