MEASURING TYRANNOSAURUS REX’S BINOCULAR VISION

Understanding the vision of extinct animals is an important part of reconstructing the ways they interacted with their environment. Other authors have evaluated the binocular vision of several theropod dinosaurs, including Tyrannosaurus rex, using miniature “life reconstruction” models, and demonstrated the association of binocular vision parameters with different feeding strategies in modern birds. For this study, my undergraduate paleontology students measured a full-size skull cast of “Stan” the T. rex to determine its binocular field of view and the extent of its anterior blind area and compared our results to those from both models and measurements of modern bird skulls. Using simple tools, we quantified visual parameters such as interpupillary distance, field of view of each eye, and snout length. Our full-size skull measurements confirmed the conclusion that T. rex had a wide binocular field of view (>50°). We also determined that the tip of T. rex’s snout fell well within its binocular field of view. Our results suggest that T. rex’s visual parameters aligned most closely with those of modern predatory birds that require visual control of their beaks to capture and manipulate prey.