Paleontologists have unearthed the exquisitely preserved remains of a Cretaceous enantiornithine bird in São Paulo state in southeastern Brazil. The skull’s extraordinary three-dimensional preservation allowed researchers to digitally reconstruct the bird’s brain.
The newly identified Enantiornithine species They lived in what is now Brazil about 80 million years ago (late Cretaceous period).
with scientific name Nabaornis Hestiathe ancient bird was about the same size as a starling.
This species had a larger cerebrum Archeopteryxsuggesting that they had more advanced cognitive abilities than early bird-like dinosaurs.
However, most regions of the brain, such as the cerebellum, are underdeveloped, suggesting that the complex flight control mechanisms of modern birds have not yet evolved.
“The structure of the brain is Nabaornis Hestia almost exactly in between Archeopteryx Dr Guillermo Navarone, a researcher at the University of Cambridge, says:
Fossilized remains are Nabaornis Hestia It was recovered in 2016 from the local Williams Quarry in Presidente Prudente, part of Brazil’s Adamantina Formation.
Tens of millions of years ago, the site was probably an arid region with slow-flowing streams, allowing for the impressive preservation of fossils.
The extraordinary three-dimensional preservation has allowed paleontologists to use advanced micro-CT scanning techniques to reconstruct the toothless, large-eyed bird’s skull and brain in stunning detail.
fossilized skeleton Nabaornis Hestia. Image credit: Stephanie Abramowitz.
“This fossil is truly one of a kind and I was in awe from the moment I first saw it to the moment I finished assembling the skull and brain. “You can fully understand the scientific structure,” Dr. Navarone said.
Professor Daniel Field from the University of Cambridge added: “Modern birds have some of the most sophisticated cognitive abilities in the animal kingdom, rivaled only by mammals.”
“However, scientists have struggled to understand when and how birds’ unique brains and remarkable intelligence evolved. The field is looking forward to discovering fossils just like this one. I’ve been waiting for it.”
On the other hand, the skull Nabaornis Hestia At first glance, it resembles a small pigeon, but upon closer inspection, it turns out that it is not a modern bird at all, but a member of the “opposite birds”, or “opposite birds”.
Birds of the order Enantiornithiformes, which diverged from modern birds more than 130 million years ago, have complex feathers and are thought to have been able to fly as competently as modern birds. .
However, the anatomical structure of the brain Nabaornis Hestia This raises new questions: How does enantiornithine behave without a range of brain features observed in living birds, including an enlarged cerebellum, which is a spatial control center in living birds? Did they control the flight?
“This fossil represents a species at an intermediate point in the evolutionary process of bird cognition,” Professor Field said.
“The cognitive ability is Nabaornis Hestia They may have had an advantage in finding food and shelter, and were capable of elaborate mating displays and other complex social behaviors. ”
“This discovery shows that some of the birds that flew above the dinosaurs already had fully modern skull shapes more than 80 million years ago,” Natural History Museum of Los Angeles County said. said researcher Dr. Luis Chiappe.
This finding is reported in the following article: paper in a diary nature.
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LM Chiappe others. 2024. Cretaceous birds from Brazil tell the story of the evolution of bird skulls and brains. nature 635, 376-381; doi: 10.1038/s41586-024-08114-4
Source: www.sci.news
