We’ve Rarely Seen a Dinosaur Brain Like This Before

“Probably this change is related with the feeding habits changing,” he said. “Carnivorous animals generally need more cognitive capabilities.”

These details about Buriolestes’s brain are intriguing because it is such an early dinosaur, said Lawrence Witmer, a paleontologist and professor of anatomy at Ohio University who studies sauropods.

“It gives us a window into the earliest evolution of the brain and sensory systems of the largest animals ever to walk on land, the sauropod dinosaurs,” he said, noting that Buriolestes’s inner ear canal and floccular lobe suggest it used quick, coordinated movements of the head, neck and eyes.

“For the slow-moving sauropods, there was no premium on retaining such capabilities, and we now know that they must have lost these capabilities,” he said, “since ancestral species like Buriolestes had them.”

Our knowledge of early dinosaur brains is very slight, said Fabien Knoll, a paleontologist at the Dinopolis Foundation in Teruel, Spain. Buriolestes, which is one of the oldest known dinosaurs, and its contemporaries are mainly found in Brazil and Argentina. When fossil remains do turn up, the skulls may be crushed or missing, making this study a rarity.

It helps illuminate a shadowy but fascinating evolutionary story — the slow transformation of small, quick, two-legged hunters into immense, unhurried quadrupeds who ate only plants.

“The study of the brain of dinosaurs is booming as it is now easier than ever to reconstruct the brain morphology thanks to digital technology,” Dr. Knoll said. “However, information about the brain in early dinosaurs is hampered by a lack of quality fossils. So I’d say that it is important to keep digging in those sites in Brazil, Argentina and elsewhere that are likely to provide well-preserved very early dinosaurs.”

source: nytimes.com