A prehistoric "highway" used by dinosaurs to travel between Africa and South America has been discovered by paleontologists, according to new research reported by CNN.
The study, published by the New Mexico Museum of Natural History & Science, reveals that matching sets of dinosaur footprints found on both continents indicate a shared migration route that existed approximately 120 million years ago, before the two landmasses split apart.
Louis L. Jacobs, a paleontologist at Southern Methodist University in Texas and lead author of the study, explained the significance of the discovery. "One of the youngest and narrowest geological connections between Africa and South America was the elbow of northeastern Brazil nestled against what is now the coast of Cameroon along the Gulf of Guinea," Jacobs said. "The two continents were continuous along that narrow stretch, so that animals on either side of that connection could potentially move across it."
Researchers have identified over 260 dinosaur footprints from the Early Cretaceous Period in Brazil and Cameroon, now separated by more than 3,700 miles across the Atlantic Ocean. The majority of these fossilized prints were created by three-toed theropod dinosaurs, with a few likely belonging to sauropods or ornithischians, according to study coauthor Diana P. Vineyard, a research associate at SMU.
The footprints were preserved in mud and silt along ancient rivers and lakes that existed on the supercontinent Gondwana. As Africa and South America began to separate about 140 million years ago, the rifting process created ideal conditions for preserving these prehistoric traces.
A team of paleontologists found matching dinosaur footprints on what are now two different continents, separated by thousands of miles of ocean.
— CBS News (@CBSNews) August 26, 2024
"Plants fed the herbivores and supported a food chain," Jacobs explained. "Muddy sediments left by the rivers and lakes contain dinosaur footprints, including those of meat-eaters, documenting that these river valleys could provide specific avenues for life to travel across the continents 120 million years ago."
The study authors found evidence of half-graben basins – elongated depressions formed by tectonic activity – in northeast Brazil's Borborema region and the Koum Basin in northern Cameroon. These basins contained not only dinosaur tracks but also ancient river and lake sediments and fossilized pollen, painting a picture of a lush, tropical environment.
While it's challenging to identify specific dinosaur species from footprints alone, the tracks provide valuable insights into dinosaur behavior and movement patterns. "Dinosaur tracks are not rare, but unlike the bones usually found, footprints are the proof of dinosaur behavior, how they walked, ran or otherwise, who they walked with, what environment they walked through, what direction they were going, and where they were when they were doing it," Jacobs noted.
The discovery of this prehistoric migration route sheds light on how continental drift influenced the evolution and distribution of dinosaur species. As the continents separated, the break in genetic continuity likely drove evolutionary changes among previously connected populations.
The research builds on decades of work, including initial discoveries of dinosaur tracks in Cameroon in the late 1980s. Jacobs and his colleague, Ismar de Souza Carvalho, a professor at the Federal University of Rio de Janeiro, have been studying dinosaur movements from the African and Brazilian perspectives, respectively.
"We wanted to put new and evolving geological and paleontological evidence together to tell a story more specifically of where and why and when dispersals between the continents happened," Jacobs said, highlighting the collaborative nature of the research.
