In a fascinating discovery, an international team of researchers led by paleontologist Louis L. Jacobs from Southern Methodist University (SMU) has found matching dinosaur footprints on opposite sides of the Atlantic Ocean.
These footprints, dating back to the Early Cretaceous period, offer a glimpse into a time when dinosaurs could freely roam between what are now South America and Africa.
Over 260 dinosaur footprints were unearthed in two distant locations: Brazil and Cameroon.
These sites, separated by more than 3,700 miles (6,000 kilometers) today, were once part of the same landmass millions of years ago.
The footprints provide evidence of a time when the continents were connected, allowing dinosaurs to migrate across the supercontinent known as Gondwana, which later split into the continents we recognize today.
According to Jacobs, the footprints are not only similar in age but also in shape and the geological contexts in which they were found.
“We determined that in terms of age, these footprints were similar,” he said. “In their geological and plate tectonic contexts, they were also similar. In terms of their shapes, they are almost identical.”
These ancient tracks were impressed into mud and silt along what were once rivers and lakes.
Most of the footprints were made by three-toed theropod dinosaurs, though some tracks may have been left by sauropods or ornithischians, according to Diana P. Vineyard, a research associate at SMU and co-author of the study.
The footprints date back 120 million years, to a time when Africa and South America were still connected.
The researchers explain that one of the last connections between these two continents was a narrow stretch of land where northeastern Brazil met what is now the coast of Cameroon.
This connection would have allowed animals, including dinosaurs, to move between the two continents before they eventually drifted apart.
The study highlights how the split between Africa and South America began around 140 million years ago. As the tectonic plates beneath the continents pulled apart, magma from the Earth’s mantle rose to the surface, forming new oceanic crust.
Over time, the widening gap became the South Atlantic Ocean, permanently separating the two continents.
The footprints were discovered in regions that bear signs of these massive geological events.
In both the Borborema region of northeastern Brazil and the Koum Basin in northern Cameroon, ancient river and lake sediments contain these dinosaur tracks, as well as fossil pollen that helps date them to 120 million years ago.
Jacobs explains that before the continents fully separated, rivers flowed and lakes formed in these areas, creating environments that supported a diverse range of life. “Plants fed the herbivores and supported a food chain,” he said.
“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.”
This discovery not only provides a deeper understanding of how dinosaurs lived and migrated but also offers a unique glimpse into the ancient world before the continents took their current shape.
The study was published by the New Mexico Museum of Natural History & Science in honor of the late paleontologist Martin Lockley, who dedicated much of his career to studying dinosaur tracks and footprints.
