A Bird from the Age of Dinosaurs Reveals the Roots of Avian Intelligence

The discovery of a Mesozoic bird fossil comparable in size to a starling could change understanding of how the unique brains and intelligence of modern birds evolved. The fossil named Navaornis hestieincludes full skull exceptionally preserved in three dimensions, a rarity for such ancient bird fossils. This discovery, made by scientists from the University of Cambridge and the Natural History Museum of Los Angeles County, provides important clues about the evolution of the brain of modern birds.

Navaorniswho lived a few years ago 80 million years in what is now Brazil, before the mass extinction that wiped out the non-avian dinosaurs, helps bridge the 70 million year evolutionary gap between Archeopteryxthe oldest known bird, and living birds. Thanks to digital reconstruction of his brain, researchers concluded that Navaornis He had a more developed brain than Archeopteryxalthough less developed than in modern birds. This indicates that it has not yet achieved the sophistication required for today’s complex flight mechanisms.

“Brain structure Navaornis ideal as an evolutionary intermediate between Archeopteryx and modern birds,” said Dr Guillermo Navalon, co-author of the study and member of the Department of Geosciences at Cambridge. According to the team, this fossil may act as “Rosetta Stone” understand the origins of avian intelligence.

The fossil was discovered in 2016 by William Nava, director of the Paleontological Museum of Marilia, at a site near Presidente Prudente, Sao Paulo. The exceptional preservation is explained dry the environment with the slow-moving streams that characterized this region millions of years ago. This allowed the researchers to use micro-computed tomography to produce extremely detailed reconstructions of the skull and brain.

Although at first glance the skull Navaornis resembling a small pigeon, it belongs to the enantiornithines, a group of primitive birds with complex plumage and the ability to fly. However, the brain Navaornis It lacked an expanded cerebellum, a key element in the flight control of modern birds, raising new questions about how primitive birds flew.

Professor Daniel Field emphasized that this fossil offers unique insight into the cognitive evolution of birds, a process that allowed some Mesozoic birds to develop complex skills such as foraging or social behavior. “This discovery demonstrates that even before the mass extinction, some birds had remarkably modern cranial geometry, paving the way for modern avian intelligence.”