Massive dinos were actually quite soft-spoken

Dinosaurs, especially larger species like the T. Rex had a deep and low voice similar to other members of the group archosaurs, which includes birds, crocodiles and alligators, a new research has revealed.

Washington, May 12 : Dinosaurs, especially larger species like the T. Rex had a deep and low voice similar to other members of the group archosaurs, which includes birds, crocodiles and alligators, a new research has revealed.

The anatomical structure of the ear of the dinosaurs was akin to that of the birds and crocodiles, and dinosaurs produced noises that were similar to the sounds they could hear, said lead author of the study, Robert Dooling.

"As a general rule, animals can hear the sounds that they produce," said Dooling, a professor of psychology and co-director of the Center for the Comparative and Evolutionary Biology of Hearing at the University of Maryland at College Park.

The team of Dooling and German neuroanatomists Otto Gleich and Geoffrey Manley, conducted comparative study on archosaur inner ear data in living animals and fossil remains of brachiosaurus, allosaurus and archeoptryx.

The researchers found that an animal's body mass is significantly correlated to the size of the individual's internal ear structure, which in turn is linked to what that creature could hear.

The findings allowed the scientists to extrapolate the hearing of the smallest bird, which weighed just around a third of an ounce, to that of huge dinosaurs like brachiosaurus, which weighed 75 tons.

The team is now of the opinion that hearing in such large dinosaurs was restricted to low frequencies with a high frequency limit below three kilohertz.

Smaller dinosaurs, however, likely could hear and emit higher frequency sounds since, as "large organisms (in general) heard best and produced sounds at lower frequencies, while smaller organisms hear best and produce sounds at higher frequencies," said Dooling.

He likened large dinosaur sounds and hearing to today's very large mammals, such as elephants.

"Since elephants can hear the footsteps of other elephants over great distances, it is probable that dinosaurs also could hear the footsteps of other dinosaurs," he said.

According to Richard Fay, director of the Parmly Hearing Institute at Loyola University, said, it was possible dinosaurs were the "strong, silent type," since "vocalizations evolved to match hearing range, and not the other way around".

According to the researchers, there is even a human link to dinosaur hearing, since, like elephants, humans possess a very low frequency range, which becomes more evident with age

"Interestingly, we sometimes irreverently refer to aging humans as dinosaurs. In fact, as we humans age in the noisy environment in which we live, we begin to lose our hearing at high frequencies," said Dooling.

"So, in a sense, our hearing becomes more like that of the dinosaurs," Discovery News quoted him as saying.

The findings will be presented this June at the Acoustical Society of America Meeting in Utah, US.

ANI