How Matching Dinosaur Footprints Ended Up on Opposite Sides of the Atlantic Ocean

Moviegoers first visited Jurassic Park in 1993, when famed director Steven Spielberg brought Michael Crichton’s dream of living dinosaurs to life on the big screen. Viewers returned for a second trip four years later in The Lost World: Jurassic Park, which expanded the territory and mythos of fictional modern dinosaurs.

The film opens on a family vacationing on the fictional island of Isla Sorna, when they are attacked by a group of small theropod dinosaurs called Compsognathus (compys, for short). The event reveals the existence of Jurassic Park’s Site B, a second location separated from the main park by the ocean. It’s where the dinosaurs are cloned before being transported to the main facility. Rather, that was the plan before a hurricane ravaged the island, after which the dinosaurs were let loose to fend for themselves.

By the time the credits roll on the second Jurassic installment, a captured T. rex is transported across the sea and unleashed on an unsuspecting San Diego. The ability of dinosaurs to survive and spread into new terrain is an ongoing theme. In the real world, about 5,000 miles south and 120 million years in the past, actual dinosaurs were also migrating, crossing an ancient continent to walk along the underdeveloped shores of a fledgling ocean.

How One Small Dinosaur Step Became One Giant Ocean-Sized Gap After 200 Million Years

Two representative theropod tracks from the Koum Basin in Cameroon. Photo: SMU

Paleontologists have discovered several sets of fossilized footprints, more than 260 in total, split between sites in Brazil (South America) and Cameroon (Africa). The prints originally formed in different parts of the same ancient continent but today they are separated by more than 3,700 miles of open ocean, on opposite sides of the Atlantic.

The footprints were made almost exclusively by three-toed theropod dinosaurs similar to The Lost World’s compys, but larger. A total of seven distinct species have been isolated: 5 theropods, ornithopod or possibly another theropod, and a sauropod. The details of the study were published in print by the New Mexico Museum of Natural History & Science, and a PDF of the paper is available online. While the specific species involved have not yet been identified, paleontologists were able to estimate hip height, speed, and body mass of each animal, based on the characteristics of the preserved prints.

Categorizing the prints revealed footsteps from what looks like the same species on both sides of the oceanic divide. A few hundred million years ago, the Earth’s landmasses were arranged in a single supercontinent called Pangaea. About 200 million years ago, Pangaea began to break apart, leaving behind two mega continents called Laurasia and Gondwana.

A precipitation map of the investigated regions, circa 120 million years ago. Red stars indicate Borborema and northern Cameroon, where the prints were found. Photo: SMU

Gondwana was made up of the modern South American, African, Indian, Antarctic, and Australian continents all smashed together. Africa and South America began to split apart about 140 million years ago and about 20 million years after that, a collection of dinosaurs created hundreds of footprints while walking along the muddy banks of ancient rivers and lakes. As the continents separated, rift valleys opened up, creating a squishy stomping ground for extinct animals.

“Rivers flowed and lakes formed in the basins," said SMU paleontologist Louis L. Jacobs, in a statement. “Plants fed the herbivores and supported a food chain. 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.”

Even without genetic modification or cushy boat rides across the sea, dinosaurs and other ancient animals found a way to spread across the globe one step at a time. And some of those steps became etched in stone so that we can walk a mile (or 3,700 of them) in the footsteps of extinct dinosaurs.

Watch Jurassic Park, The Lost World, and the rest of the Jurassic series, available now from Universal Pictures.