New Study Shows Pterosaurs Built Flight-Ready Brains Independently Of Birds

How Pterosaurs Evolved Their Own Neural 'Flight Computers'

ATHENS — A new study in Current Biology, co-authored by Ohio University anatomist Lawrence Witmer and an international team of researchers, reveals how pterosaurs evolved the neural machinery for powered flight independently from birds. Using high-resolution 3D imaging and statistical shape analysis of cranial endocasts, the team traced stepwise changes in brain anatomy across a broad sample of archosaurs.

Key Fossil: Ixalerpeton

The discovery of a 233-million-year-old lagerpetid named Ixalerpeton from Brazil provided a crucial comparative data point. Ixalerpeton shows early visual specializations — such as an enlarged optic lobe — that may have helped pave the way for aerial behavior. But it lacks other pterosaur-defining neural features, demonstrating that some flight-related brain adaptations evolved after pterosaurs diverged from their close relatives.

Methods: Micro-CT And Endocast Analysis

Researchers scanned more than three dozen species — including pterosaurs, lagerpetids, early dinosaurs and bird precursors, modern birds and crocodilians, and other Triassic archosaurs — using micro-CT and other high-resolution imaging. They reconstructed cranial endocasts (3D models of brain shape) and applied statistical shape analysis to map anatomical trends tied to flight.

Findings: Different Paths To Flight

Contrary to the idea that powered flight requires a very large brain, the study found that pterosaurs retained relatively small overall brain sizes compared with birds. Instead, pterosaurs evolved targeted specializations — notably a greatly enlarged flocculus, a cerebellar region likely important for processing sensory feedback from membranous wings and stabilizing gaze during flight.

"It apparently doesn't take a large brain to get into the air," said Lawrence Witmer. "Pterosaurs built their own 'flight computers' differently from birds, which inherited much of their brain layout from theropod ancestors."

Surprisingly, the overall brain shape of many pterosaurs most closely resembled that of small, birdlike theropods (for example, troodontids and dromaeosaurids) — groups that had little or no powered flight. This highlights that birds and pterosaurs represent two distinct evolutionary experiments in aerial locomotion: birds adapted a brain already shaped by their dinosaur ancestry, while pterosaurs evolved flight-capable neural traits concurrently with their wings.

Broader Implications

The authors suggest that later brain enlargement in birds was likely driven more by selection for higher cognition and complex behaviors than by flight itself. The study also underscores the continuing importance of fieldwork — especially in southern Brazil — in illuminating the early evolution of major archosaur lineages.

Authors and Funding: The paper includes Mario Bronzati, Akinobu Watanabe, Roger B. J. Benson, Rodrigo T. Müller, Lawrence M. Witmer, Martín D. Ezcurra, Felipe C. Montefeltro, M. Belén von Baczko, Bhart-Anjan S. Bhullar, Julia B. Desojo, Fabien Knoll, Max C. Langer, Stephan Lautenschlager, Michelle R. Stocker, Alan H. Turner, Ingmar Werneburg, Sterling J. Nesbitt, and Matteo Fabbri. Funding came from multiple international agencies, including the Alexander von Humboldt Foundation, Brazilian federal programs, the U.S. National Science Foundation, and others.

Caption note: Artistic reconstructions show a pterosaur and a lagerpetid from the Late Triassic (about 215 million years ago), alongside 3D brain reconstructions produced by computed tomography scanning.