Ancient Crocodiles Swam from Africa to North America
A fossil found in Libya closely connects the animal to its American family
An examination of a fossilized skull from an extinct crocodile ancestor suggests that crocodiles may have ventured from Africa to North America a few million years ago.
The fossil, which was actually discovered in the 1930s, was discovered in Libya, and kept in a museum for years. A computerized topography (CT) scan of the skull found that it is very similar to today’s American crocodiles. The Crocodylus checchiai, which is now extinct, had previously been closely linked to American crocodiles based on genetic analyses, but it was never clear if the reptiles started in North America and ventured east, or if they started in Africa, and migrated westwards.
The fossilized skull, which is estimated to be around 7 million years old, is older than any known fossil from crocodiles in the Americas. The skull of the C. checchiai, an animal closely related to both the Nile Crocodile and the four species in the Americas, fills a gap between the two, and how they separated from each other.
When the C. checchiai existed on Earth, the Americas and Africa were roughly in the same place as they are now, meaning that crocodiles at some point made the trip across the Atlantic Ocean to reach the Americas.
Massimo Delfino, a paleohereptologist at the University of Turin, in Italy, explains, “It’s not so surprising given today’s crocodilians’ abilities to survive in saltwater and to travel hundreds of kilometers, especially in ocean currents.”
While researchers and scientists aren’t 100% certain about the claim, like everything else in science, the evidence surrounding the fossil and its evolutionary implications are very compelling, and help to explain how two species of Crocodiles can be so similar, while being on opposite sides of the world.