Researchers studied horse voices using anatomy, clinical records and sound recordings. They wanted to know how one whinny can have two very different tones at once.
They found the low frequency comes from vocal‑fold vibration, the same mechanism people use to sing. The high frequency comes from a laryngeal whistle, where turbulent air makes a whistle sound inside the larynx.
To test this, the team blew air through larynges removed from deceased horses and switched between air and helium. The whistle tone rose with helium while the low tone stayed the same. This shows horses can make two sounds at once.
Difficult words
- larynx — the organ in the throat for making soundlarynges
- frequency — how high or low a sound is
- vibration — fast movement that makes a sound
- turbulent — air that moves in a rough, mixed way
- helium — a light gas used in experiments
- whistle — a high clear sound made by air
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Have you heard a horse whinny before? What did it sound like?
- Do you think other animals can make two different sounds at once? Why or why not?
- Would you like to study animal sounds? Why or why not?
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