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The Oldest Bird Voice Box Ever Found - The New York Times

A new study of a 66-million-year-old bird may provide insight into some of the noises possibly heard at the end of the dinosaur era.

Researchers studying the fossilized remains of an Antarctic waterfowl called Vegavis iaai discovered within its chest the oldest known avian voice box, called a syrinx. The finding, published Wednesday in Nature, suggests that the ancient bird “honked” and “quacked” like today’s geese and ducks.

Mammals like humans and reptiles like crocodiles make noises by vibrating vocal folds in their larynxes, which is in the back of the throat. But for birds, their chirps, squawks and tweets come from a specially-evolved organ called the syrinx, which is in the windpipe where it branches into the left and right lungs.

“It’s essentially like having your voice box deep in your chest right next to the heart,” said Julia Clarke, a paleontologist from the University of Texas at Austin, and lead author of the study.

The syrinx is hard to find in ancient bird specimens because it is made of calcified cartilage that does not typically fossilize well. Only a handful that are older than a few million years old have ever been found. It took nearly two decades to uncover the syrinx in this specimen, and Dr. Clarke said she did not set out to discover it.

Vegavis iaai was originally found on Vega Island in Antarctica in 1992 by Argentine researchers. Years later, they gave it to Dr. Clarke to analyze. She and her team classified it in 2005. In 2013 while Dr. Clarke was coincidentally working on a project on the evolution of dinosaur and bird vocalization, she decided to take another look at the specimen’s vertebrae before returning it. Embedded in the rock, she discovered the syrinx.

“I was like ‘Oh my gosh.’ I couldn’t believe it. We had been asking this question ‘What would fossil data look like that could add to our understanding of avian sound making?’” she said. “And then I’m rechecking a specimen in my lab that I had for five years, and there it is. That was kind of crazy.”

Using CT scans, she compared the ancient syrinx to that of 12 other modern birds as well as another ancient fossil, and found that the organ was most closely related to those seen in ducks and geese. The finding suggests that birds, which are living dinosaurs, evolved the organ relatively late in their evolutionary line.

Researcher discovers ancestor of biggest bird ever

A newly discovered distant relative of the duck has just been hailed as an ancestor of the biggest bird the world has ever known by a group of Australian palaeontologists.

They say Dromornis murrayi, which at 250kg was originally the 'baby' of the ancient 'Mihirung' family of Dromornis giant birds, eventually evolved into the world's biggest bird, D. stirtoni, before going extinct.

"It lived in the late Oligocene – early Miocene, and was the first member of the lineage of Dromornis species," says Dr Trevor Worthy, from Flinders University in South Australia, who led the study.

"Originally, it was the smallest, at a pretty hefty 250 kg, but by eight million years ago it had evolved into D. stirtoni, which averaged a whopping 450 kg – with some individuals reaching 650 kg – the largest birds the world has known."

Dr Worthy's team of palaeontologists, from Finders University and University of New South Wales, revealed the news in a study just published in the Journal of Vertebrate Paleontology.

"Mihirungs were giant flightless birds only found in Australia and are known only from fossils," said Dr Worthy. "The largest stood two metres high at its back and reached well over three metres at the head.

"They survived until the Pleistocene period when Genyornis newtoni, the last species, died out, probably about 50,000 years ago."

Seven species in four genera of the bird are generally recognised, with the last five named in 1979 by Patricia Vickers Rich, now a Professor at Monash University.