Supervisors and Institutions
Dinosaurs are iconic animals because of their long evolutionary history, the immense sizes of some species, and the many ways in which they adapted to an ever-changing world in the Mesozoic (ca. 231-66 million years ago). The anatomy, genealogy, and lifestyles of dinosaurs have been the subject of intensive study, and we have a good understanding of how many species moved, ate, and reproduced. Much less is known, however, about the brains, sensory systems, and intelligence of dinosaurs, because brains and sensory organs do not normally fossilize. Over the last few decades, computed tomographic (CT) scanning of dinosaur skulls has unlocked the potential to study dinosaur neuroanatomy. This has revealed that dinosaurs had a variety of brain shapes and sizes, and that while their brain sizes relative to body sizes were generally in the ‘reptilian’ zone of modern animals, some species (like advanced bird-like theropods) had much larger brains (and thus likely intelligence) than previously thought. It has also been found that some species had particularly large or tiny brain regions corresponding to certain senses and behaviours, such as olfaction and balance. Most studies thus far, however, have been incremental. A new dinosaur species may be described, and its brain shape commented on; the size or shape of the brain may be analysed across a subgroup of dinosaurs, such as theropods. However, there has yet to be a systematic analysis of brain size and shape evolution across all Mesozoic dinosaurs, over time and across phylogeny. This leaves several fundamental questions unanswered: how did dinosaur brains and senses develop over time and space, were some species brainier or endowed with better senses than others, and what were the key drivers of dinosaur neurosensory evolution? Such work has recently been conducted for mammals, by our research group and others. We will now use these techniques—CT and phylogenetic statistical methods—to study dinosaurs.