According to [a] new study, Buriolestes schultzi’s brain had an elongated shape and weighed about 1.5 grams, as much as a pea, Tibi Puiu writes for ZME Science. That’s pretty small for an animal. For comparison, a similarly-sized fox has a 53 gram brain. But relative to its body size, Buriolestes had more brain power than its descendants.
Over the course of about 50 million years spanning the late Triassic period and the early Jurassic Epoch, the two-legged, carnivorous Buriolestes’ lineage evolved into gigantic, four-legged, plant-eating sauropods. While the dinosaurs grew bigger, their brains didn’t keep up. By the time the sauropods, like brontosaurus, reached 100 tons and 110 feet long, their brains were only the size of tennis balls.
This feature is strange because usually, evolution favors larger brains over time. The new study revealed other changes in the brain structure between Buriolestes and sauropods, too. While the early dinosaur had small olfactory bulbs, sauropods had large ones, meaning their sense of smell improved over time, [researcher Rodrigo] Müller tells SWNS.
“It gives us a window into the earliest evolution of the brain and sensory systems of the largest animals ever to walk on land,” says [paleontologist Lawrence] Witmer.
