(Press-News.org) Lions' and tigers' fearsome roars are due to their unusual vocal cords, according to a study published in the Nov. 2 issue of the online journal PLoS ONE. The authors report that the big cats' vocal cards have an odd square shape and can withstand strong stretching and shearing. That shape "makes it easier for the tissue to respond to the passing airflow," allowing louder roars at lower lung pressure, says University of Utah researcher Tobias Riede, one of the researchers involved in the project.
These findings contradict a theory that lions roar deeply because the vocal folds are heavy with fat. Instead, the researchers speculate that the fat gives the vocal folds their square shape (as opposed to the more traditional triangular vocal folds found in most species), and may cushion the vocal folds and provide repair material when they are damaged.
"If you understand how vocal folds are structured and what effects that structure has on vocal production, then it could help doctors make decisions on how to reconstruct damaged vocal fold tissue" in people such as cancer patients, singers, teachers, coaches and drill sergeants, Riede says.
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Citation: Klemuk SA, Riede T, Walsh EJ, Titze IR (2011) Adapted to Roar: Functional Morphology of Tiger and Lion Vocal Folds. PLoS ONE 6(11): e27029.doi:10.1371/journal.pone.0027029
Financial Disclosure: Funding for this work was provided in part by National Institutes of Health (NIH) Grants R01 DC008612, R01 DC04390, and 1R01 DC010275, and National Science Foundation (NSF) Grant 0823417. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing Interest Statement: The authors have declared that no competing interests exist.
Disclaimer: This press release refers to upcoming articles in PLoS ONE. The releases have been provided by the article authors and/or journal staff. Any opinions expressed in these are the personal views of the contributors, and do not necessarily represent the views or policies of PLoS. PLoS expressly disclaims any and all warranties and liability in connection with the information found in the release and article and your use of such information.
About PLoS ONE: PLoS ONE is the first journal of primary research from all areas of science to employ a combination of peer review and post-publication rating and commenting, to maximize the impact of every report it publishes. PLoS ONE is published by the Public Library of Science (PLoS), the open-access publisher whose goal is to make the world's scientific and medical literature a public resource.
All works published in PLoS ONE are Open Access. Everything is immediately available -- to read, download, redistribute, include in databases and otherwise use—without cost to anyone, anywhere, subject only to the condition that the original authors and source are properly attributed. For more information about PLoS ONE relevant to journalists, bloggers and press officers, including details of our press release process and our embargo policy, see the everyONE blog at http://everyone.plos.org/media.
Born to roar
2011-11-03
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