Cassowary Calls Give Insight To Dinosaur Communication

["Richard W. Travsky" <rtravsky@uwyo.edu>]

http://wcs.org/7411/?art=110481374

World's Largest Forest Birds May Produce World's Deepest Bird Calls

A family of huge forest birds living in the dense jungles of Papua New
Guinea emit low-frequency calls deeper than virtually all other bird
species, possibly to communicate through thick forest foliage, according
to a study published by the New York-based Wildlife Conservation Society.

Published in the recent issue of the scientific journal The Auk, the study
says that three species of cassowaries - flightless birds that can weigh
as much as 125 pounds - produce a booming call so low that humans may not
be able to detect much of the sound.  The researchers draw similarities
between the birds calls and the rumbling elephants make to communicate.

When close to the bird, these calls can be heard or felt as an unsettling
sensation, similar to how observers describe elephant vocalizations, said
WCS researcher Dr. Andrew Mack, the lead author of the study.
...
The authors and their collaborators are now pursuing studies that examine
the physics of low frequency sound production and reception. They
speculate that the cassowaries casque might serve a function in both, most
likely sound reception.

These investigations are exciting because many dinosaur fossils exhibit
casques at least superficially similar to those of living cassowaries,
said Mack.  No one knows for sure what purpose these served in these
dinosaurs, so further study of living cassowaries might provide clues to
how dinosaurs communicated."

Coincidentally, the great early 20th Century dinosaur hunter, Barnum
Brown, described the Corythosaurus, otherwise known as the Corinthian
Helmet Lizard as cassowary-like.