The study led by SMU paleontologist Louis L. Jacobs discovered matching sets of Early Cretaceous dinosaur footprints in Brazil and Cameroon, showing where land-dwelling dinosaurs were last able to freely cross between South America and Africa before the continents split apart. The footprints, more than 3,700 miles apart, were found to be similar in age, geological context, and shape, suggesting they were made by dinosaurs 120 million years ago on the supercontinent of Gondwana. The findings shed light on a narrow geological connection between Africa and South America, providing insight into the movement of animals across continents during ancient times.
The majority of dinosaur footprints discovered in the study were made by three-toed theropod dinosaurs, with some likely created by sauropods or ornithischians. The tracks were impressed into mud and silt along ancient rivers and lakes, providing a glimpse into the ecosystems that existed on the supercontinent of Gondwana millions of years ago. The researchers, including co-author Diana P. Vineyard, a research associate at SMU, analyzed the footprints to understand the behavior and movement of dinosaurs in this prehistoric landscape.
The study, published by the New Mexico Museum of Natural History & Science, was a tribute to the late paleontologist Martin Lockley, who dedicated much of his career to studying dinosaur tracks and footprints. The researchers involved in the study collaborated to investigate the geological and paleontological significance of the matching sets of dinosaur footprints found in Brazil and Cameroon, providing valuable information about the ancient connections between Africa and South America.
The splitting of Africa and South America around 140 million years ago created rifts in the Earth’s crust, leading to the opening of rifts and the movement of tectonic plates. As the continents moved apart, magma from the Earth’s mantle rose to the surface, creating new oceanic crust and eventually forming the South Atlantic Ocean. The footprints discovered in the Borborema region in Brazil and the Koum Basin in Cameroon provide evidence of these major geological events, highlighting the ancient processes that shaped the continents and ocean basins.
The presence of half-graben basins and ancient river and lake sediments in both locations where dinosaur footprints were found indicate the presence of a diverse ecosystem that supported various species of dinosaurs. The fossil pollen found in these sediments suggests an age of 120 million years, providing a timeline for when these footprints were made. The researchers emphasize that the rivers and lakes in these basins played a crucial role in supporting life and facilitating the movement of dinosaurs across the continents during the Early Cretaceous period.
Overall, the matching sets of dinosaur footprints found in Brazil and Cameroon offer valuable insights into the prehistoric world of Gondwana and the connections between ancient ecosystems in Africa and South America. The study contributes to our understanding of dinosaur behavior, movement, and the geological processes that shaped the Earth millions of years ago. By studying these footprints, researchers can piece together the story of how dinosaurs roamed the supercontinent and crossed between continents before they were separated by the shifting tectonic plates.