SALT LAKE CITY — You may not know it by hearing it, but lions and human babies have something in common: they both cry out for attention.
Researchers at the University of Utah's National Center for Voice and Speech have found that a baby's cry and a lion's roar are only different by the fact that a lion's vocal cords vibrate at a lower frequency.
"Roaring is similar to what a baby sounds like when it cries," said speech scientist Ingo Titze, executive director for the center. "In some ways, the lion is a large replica of a crying baby, loud and noisy, but at a very low pitch."
A new study of lion and tiger vocal cords, and how they work, was produced by the Utah researchers and published this week in the Public Library of Science's online journal PLoS ONE.
While a side observation to the study, researches said both babies and lions use rough vocals to get attention. "In both cases, we hear loud, grating sounds that grab people's ears. When a baby cries, the sound isn't pretty. The sound is basically rough. The vibration isn't regular," Titze said. In contrast, human voices are smooth and controlled.
The comparison is just a small part of research being done in studying the vocal cords of a variety of animals.
"There is not a single species that's identical to humans," said assistant biology professor and study co-author Tobias Riede.
Riede said the center teamed up with an out-of-state researcher who had several older lions. Researchers recorded the voices of the lions. Post-mortem, they then studied the structure of their vocal cords.
The group has also studied several species of deer, elk, dogs and cats.
The goal is to be able to predict the audio properties of vocal cords through their physical shape. By doing this, doctors will be able to more accurately reconstruct damaged human vocal cords, helping everyone from average people, to professional singers and actors, Riede said.