Scotland, once a desert over 250 million years ago, now experiences a misty, rainy climate. In this ancient landscape, Gordonia, a mammalian precursor resembling a squat, pig-like creature with a pug face and two tusks, roamed. Researchers used advanced three-dimensional imaging on a Permian Period fossil to examine its brain cavity, creating a digital model that sheds light on early mammalian brain size and composition. Gordonia, part of the group of protomammals that retained reptilian characteristics, lived approximately 254–252 million years ago. Despite its evolutionary proximity to mammals, Gordonia’s brain, much smaller than those of modern mammals, exhibited intelligence crucial for mammalian dominance, resembling more the brains of reptiles. Hady George, a doctoral student in paleontology at the University of Bristol and lead author of the study published in the Zoological Journal of the Linnean Society, noted this resemblance.

George noted that Gordonia’s forebrain, crucial for advanced cognitive functions, was notably smaller compared to modern mammals. However, an organ known as the pineal gland, enlarged in Gordonia, plays a significant role in metabolic functions. Steve Brusatte, a paleontologist at the University of Edinburgh and senior author of the study, remarked on the unusual shape of Gordonia’s brain—a long, arched tube rather than a rounded structure. Despite its unconventional appearance, the brain’s volume was relatively large compared to the creature’s body size, suggesting early signs of evolutionary development. This research underscores how ancient mammals like Gordonia laid the groundwork for the cognitive advances that later enabled mammals, including humans, to thrive on Earth. By studying these early mammalian ancestors, scientists gain valuable insights into the evolutionary pathways that shaped the development of complex brains and intelligence across millions of years.