Analysis of the acceleration phase of a theropod dinosaur based on a Cretaceous trackway from Korea

Well-preserved trackways of carnivorous dinosaurs belonging to small-sized theropods have been reported from the Cretaceous Neungju Group in South Korea. The site at Hwasun Seoyu-ri Quarry represents the most extensive and diverse theropod trackway ichnofauna in South Korea. Among them, one theropod trackway is unique in that it demonstrates that theropods were able to increase stride lengths to reach maximum speed, during the running phase. Fossilized track evidence of the acceleration ability of dinosaurs is scant. Despite this, the evidence shown in our findings suggests a theropod running near the limit of its capabilities and shows evidence of a temporary acceleration of speed while running.