There shouldn’t be a movie with (or about) dinosaurs that doesn’t include, at some point, the powerful and terrifying roar of a Tyrannosaurus Rex, but it’s looking increasingly unlikely that this was how the species called itself.
There are no certainties, since, of course, sound doesn’t fossilize and no one is here to tell a story that ended 66 million years ago. But researchers suspect a sound similar to that of the foggy, which seems to resonate in our bodies. Yes, you can hear it, but you can definitely feel it.
With the help of advanced analytical techniques, scientists are looking into recently found rare fossils to try to piece this puzzle together. A key piece was discovered in 1995 by paleontologists at the New Mexico Museum of Natural History and Science: an entire skull from Parasaurolophus, a herbivore that could move using all four legs as well as only the two hind legs. The images obtained through computed tomography allowed the researchers to observe, in greater detail than ever before, the top of this animal and to digitally reconstruct this organ, simulating the resonance of the air passing through it, with or without vocal organs, such as the larynx or something similar. . Even without this “device,” they concluded, the Parasaurolophus it could have emitted a sound thanks to the reverberation of the air expelled inside the top.
“I would describe the sound as ‘out of this world,'” says Tom Williamson, one of the paleontologists involved in the dig and now curator of the area at the museum. To test an analogy with a sound produced by an animal that is still alive, the expert turns to the cassowary, a flightless Australian bird that emits a series of sounds that echo through the jungle where they live.
Julia Clark is a paleontologist from the University of Texas who, in the middle of the last decade, devoted herself to examining the fossil of a bird that would have coexisted with dinosaurs in the Cretaceous period and discovered a syrinx, an organ found in birds. responsible for the production and broadcasting of sounds. For Clarke, the fact that this organ was fossilized raised a question: why were no dinosaurs found? This doubt led the scientist to deepen the research and reach a conclusion that contradicts everything we believe about the vocalization of dinosaurs: it is almost certain that they did not roar. They probably cooed like pigeons.
“The Jurassic Park movies got it wrong,” laughs Clarke, who believes many dinosaurs may have made sounds with their mouths closed.
The ear anatomy of these animals is another clue in this direction, and here there is a fossil record that supports the theory. Phill Manning, professor of natural history at the University of Manchester, explains that dinosaurs had only one bone in the middle ear, the stapes – a fundamental structure in translating sound waves into the inner ear so that they could later be processed by the brain – , while mammals, in addition to the stribuus, still have the hammer and anvil (the names are due to the resemblance to these objects, as it is easy to imagine).
Without these last two, dinosaurs would probably only be able to hear a much smaller range of frequencies compared to mammals.
“The dinosaur stirrer was quite large, about the size of a matchstick in the T-Rex, which means it was well tuned to lower frequencies,” Manning continues, according to the BBC. On the other hand, the dimension of the cochlear ducts of the inner ear suggests that, in general, the species was capable of picking up high-frequency sounds.
Cochlear elongation, which indicates sensitivity to high-pitched noises, appeared near the origin of the group that included birds and crocodiles, and Bhart-Anjan Bhullar, associate curator of vertebrate paleontology at the Peabody Museum of Natural History at Yale University, adds that after several reconstructions and studies, the only explanation consistent with all that is known has to do with a transition to a higher level of parental care. This sensitivity to louder sounds will then be used to identify the young.
Since such large animals can produce such a wide variety of sounds, the question remains: how would they sound to human ears? Many, some researchers believe, will not listen to us. Low-frequency sounds and ultrasounds are especially useful for long-distance travel, both in open spaces and in dense habitats such as the jungle, but so low that we would hardly pick them up. And they certainly wouldn’t sound like “roarrrrrrrr”…