New Research Reconstructs a Dinosaur’s Pea-Sized Brain
Discovery of a Well-Preserved Skull
Scientists have reconstructed the brain of an early dinosaur, Buriolestes schultzi, thanks to the discovery of a fossil with an unusually well-preserved skull. The skull belonged to a fox-sized carnivore that lived in what is now Brazil about 230 million years ago.
CT Scanning Reveals Brain Structure
Using computed tomography (CT) scanning, researchers were able to map the shape of the braincase and determine how the brain would have fit inside. Details of the skull’s shape provided clues to the sizes of different brain structures.
Comparison to Modern Animals
The Buriolestes brain had a similar structure to that of a crocodile, with a significant portion dedicated to vision processing and relatively little to the sense of smell. For comparison, a similarly-sized fox has a much larger brain, weighing 53 grams compared to Buriolestes’ 1.5 grams.
Evolution of the Dinosaur Brain
Over time, the descendants of Buriolestes evolved into gigantic, plant-eating sauropods. While the dinosaurs grew larger, their brains did not keep up. Sauropods like Brontosaurus had brains only the size of tennis balls, despite their massive size of up to 100 tons and 110 feet in length. This trend is unusual, as evolution typically favors larger brains over time.
Sensory Adaptations
The new study also revealed changes in the brain structure between Buriolestes and sauropods. While Buriolestes had small olfactory bulbs, sauropods had large ones, indicating an improved sense of smell over time. This development may be related to the acquisition of more complex social behaviors or improved foraging abilities.
Vision and Prey Tracking
Researchers speculate that vision processing was crucial for Buriolestes as a hunter, as it needed to track prey and avoid larger carnivores. In contrast, sauropods, which ate only plants, had less need for acute vision. Later carnivorous dinosaurs, such as velociraptors and Tyrannosaurus rex, had larger brains than Buriolestes, reflecting their more advanced hunting strategies.
Significance of the Discovery
The new study provides valuable insights into the early evolution of the dinosaur brain and sensory systems. It highlights the importance of preserved dinosaur skulls in brain research and sheds light on the relationship between brain size, body size, and behavior in these prehistoric animals.
