… did birds begin to sing? The soundscape of deep time is coming back
"In late 2016, a team of palaeontologists, led by Julia Clarke from the University of Texas at Austin, confirmed they had discovered the oldest known fossil of a bird's voice box, known as a syrinx. It was found in the remains of an extinct Antarctic bird named Vegavis, which died at least 66 million years ago and lived alongside the dinosaurs. The fact that the syrinx was not more widespread at the time suggests that the bird's voice box arrived relatively late in the evolutionary game, some time after flight, the development of continuous breathing and the use of colourful feathers for sexual display.
The syrinx was made up of tough cartilage, and in this case was unusually well-preserved. ‘We got exceptionally lucky,' says Clarke. But the specimen was still not enough to identify the bird's call. Bird sounds are complex, shaped by factors including the folds of tissue that cover the cartilage and the structure of the rest of the vocal tract. So the team compared the fossil to 12 species of living birds, and one species of ancient waterfowl, in order to build up a three-dimensional model of the creature's acoustic anatomy. The results suggested Vegavis might have made a sound akin to either a duck or a goose. ‘Whether it is a quacker or a honker, we don't actually have the data at this point to say,' adds Clarke.
Fossils are lifeless and yet full of life – packed with not only the shapes and forms of the creatures they came from, but also with their habits, movements and more subtle and surprising traces of how ancient animals perceived the world. Take the dinosaurs, those pop-icons of palaeontology. Fossilised footprints reveal that they travelled in herds, hunted in packs or nurtured offspring that stuck close to their mother's footsteps. Pigment-bearing cells preserved in hair follicles give us a glimpse of the colours of dinosaurs' coats (blacks, reddish-browns), and we know that they could be scaled or feathered. Even the fearsome T Rex was fluffy. Now, through the unyielding materiality of fossils, scientists over the past two decades have come to a much richer understanding of the most elusive and atmospheric feature of the primordial world: its soundscap…"
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