Ancient Antarctic birds had a beaked spear that revealed the world of lost bird diversity

A huge preserved 70 million bird skull found in Antarctica is providing an unprecedented window for the early evolution of modern birds, challenging long-term assumptions about its ancient relatives. The fossil belongs to Vegavis iaai, a unique duck bird that attracts Antarctic water next to the dinosaurs, waving a unique spear-shaped beak, unlike any of its modern relatives.

This discovery, published in nature, is one of the most complete bird bone skulls found in the last chapter of the dinosaur era. What makes it particularly important is that it not only includes the skull, but also provides insights into the brain structure of the creature – which are birds from this period.

“Very few brains can illuminate this stage of bird evolution,” said Chris Torres, an assistant professor at the Pacific University who led the study.

The fossil was excavated on Vega Island in Antarctica in 2011 and was excavated during a fossil expedition by Eric Roberts, a professor at the Colorado School of Mining. It adds an increasing collection of Vegavis specimens that greatly enhance our understanding of early bird evolution.

Julia Clarke, a professor at UT Jackson College of Earth Sciences, said Vegaves has been studying for nearly two decades, and the unique characteristics of skeletons have forced scientists to rethink what ancient birds look like. The spear-like beak, in particular, contrasts with what researchers expect to find among the early relatives of ducks and gooses.

“I think it made some people stop,” Clark said. “They expect [the skull] More like a duck or a goose. ”

This finding helps resolve long-term debates about Vegaves’ fitting position in bird genealogy. Although some researchers believe it is only related to modern birds, the new analysis has placed it firmly in Anseriformes, including today’s ducks and geese. This location is of great significance to understanding when modern birds first emerge.

Torres noted that few ancient birds have caused scientific discussion like Vegavis, noting that “few birds, like Vegavis, have been among paleontologists. Start with so many arguments.”

The study shows that modern bird ancestry has diversified before the extinction of non-Archi dinosaurs were eliminated. This shows that birds are not only the opportunistic successors of dinosaurs, but are actively developing with dinosaurs.

Patrick O’Connor, professor at Ohio State University and director of Earth and Space Science at the Denver Museum of Nature and Science, emphasized the broad significance of Antarctic fossils during this period. “This new fossil shows that there are a lot to tell us about the earliest stages of modern bird evolution,” he said.

The study depicts a more diverse picture of the paleobi world than previously thought. Although today’s ducks and geese represent limited body forms, their ancient relatives exhibited extensive adaptations. Some of the ancient duck relatives are more like today’s herons or flamingos, while Vegaves seems to be a professional underwater hunter.

“In the past, they were weird, great,” Clark said. “We have a big range.” [of now-extinct anseriform birds] Vegaves agrees with it. ”

The exquisite preservation of fossils allows researchers to not only study the external features of the skull, but also reconstruct the internal brain shape – a rare opportunity to provide new insights into the neural evolution of early birds. Brain structures show characteristics of modern birds, including brain enlargement, suggesting that key aspects of modern avian neurology have been established by the Late Cretaceous system.

The research team also includes Joseph Gronick of Ohio University, Matthew Ramanna of the Carnegie Museum of Natural History, Ross McPhee of the American Museum of Natural History, and Grace Musser of UT Austin and Smithsonian National Nature. History Museum. The research was funded by the National Science Foundation.