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"... but the fossil record provides a minimum date: a katydid from around 250 million years ago has the sound-producing anatomy characteristic of this group. The earliest-known fossils of cicada relatives also date to this time. These insects can generate exceptionally loud sounds by rapidly buckling and unbuckling drumlike structures on their bodies called tymbals. The sound-production structures are so well preserved in some insect fossils that researchers can reconstruct the songs the creatures sang in life. In 2011 a team led by Jun-Jie Gu, now at Sichuan Agricultural University in China, worked out that a specific ancient katydid emitted songs tuned to a frequency of 6.4 kilohertz ...
Today’s amphibians, reptiles and mammals all possess a larynx, or voice box, near the top of their airway. This fact suggests they inherited it from their last common ancestor, which would mean the larynx is nearly as old as land vertebrates themselves, going back 300 million years or so. It probably took millions of years for truly specialized or powerful vocalizations to evolve in these animals, however. Little is known about these early stages of vertebrate vocalization, not least because the larynx is made up of cartilage, which generally does not preserve well. What we do know is that starting roughly 230 million years ago, during the Mesozoic era, vertebrate animals evolved a wide range of vocal abilities. ...
Scientists do not yet have a firm grasp on the origins of the syrinx. The oldest avian syrinx discovered to date comes from a specimen of the extinct bird Vegavis, described in 2016 by Clarke and her colleagues. Vegavis lived during the latest part of the Cretaceous period, 66 million to 69 million years ago. But its syrinx was already fairly specialized, with its expanded resonating space and asymmetry associated with dual-sided sound production."
Today’s amphibians, reptiles and mammals all possess a larynx, or voice box, near the top of their airway. This fact suggests they inherited it from their last common ancestor, which would mean the larynx is nearly as old as land vertebrates themselves, going back 300 million years or so. It probably took millions of years for truly specialized or powerful vocalizations to evolve in these animals, however. Little is known about these early stages of vertebrate vocalization, not least because the larynx is made up of cartilage, which generally does not preserve well. What we do know is that starting roughly 230 million years ago, during the Mesozoic era, vertebrate animals evolved a wide range of vocal abilities. ...
Among the most acoustically talented animals in the Mesozoic were the dinosaurs. In 1981 ... carried out one of the first reconstructions of a fossil animal’s vocalization, working with the herbivorous, duck-billed dinosaur Parasaurolophus. ...
Since 2008 ... team have been using CT scans, along with fluid mechanics modeling, to assess sound production in various dinosaur species. They have discovered that the skulls of many dinosaurs contained complex chambers. Air flow through these spaces would have been correspondingly convoluted. The air flow helped to regulate body temperature, but it also might have enabled the animals to produce a wide array of sounds, including honks, bellows and trumpets. ...Scientists do not yet have a firm grasp on the origins of the syrinx. The oldest avian syrinx discovered to date comes from a specimen of the extinct bird Vegavis, described in 2016 by Clarke and her colleagues. Vegavis lived during the latest part of the Cretaceous period, 66 million to 69 million years ago. But its syrinx was already fairly specialized, with its expanded resonating space and asymmetry associated with dual-sided sound production."
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