What did the Dino say?


Unfortunately, we don’t know exactly, for the living tissue which is used to create sound isn’t easily fossilizable and leaves us with very few clues. Movies, like Jurassic World, basically utilize a bit of imagination and fantasy to create the roaring and the sounds of the dinosaurs. The sounds used in movies are often mash ups of different sounds coming from a variety of sources. (More on that in the link below) Despite this difficulty to pinpoint the noises of dinosaurs, there has been research on the acoustics of ancient organisms that could give us a few clues.
Many tetrapods, vertebrates with four limbs, make sounds using vocalization, the vibration of vocal folds. This is how humans, amphibians, birds, crocodiles, and other organisms produce sound. Archosauria, a clade that consists of crocodiles, birds, and dinosaurs, may give us the most information. Crocodiles use the larynx, while birds use the syrinx as their vocal organ. There has been research, showing that crocodiles vocalized with bellowing and head-slapping, a display of courtship and dominance, but I digress.
The syrinx that belongs to birds is a structure made of cartilage rings at the intersection of the trachea and primary bronchi. For the syrinx to vibrate and produce noise, there needs to be something called the clavicular air sac which actually emerges from the fusion of two air sacs hat were developed previously. Since the clavicular air sac is made from preexisting structures, it probably came along later in evolutionary history. Sadly, there is no strong evidence that dinosaurs had a clavicular air sac homologous to the one in birds. The lack of support for the syrinx in dinosaurs doesn’t necessarily make them mute though. Living reptiles today communicate with hissing, grinding their lower and upper jaws together, splashing, etc. Even birds use hissing, wing beating, and bill-clapping. It is kind of weird to think that the T-Rex couldn’t roar like in the movies, but it is fun to think about.
Works Cited
Senter, Phil. “Voices of the Past: A Review of Paleozoic and Mesozoic Animal Sounds.”Historical Biology 20.4 (2008): 255-87. Web.