Millions of years ago, crocodiles in Africa undertook a wild journey across the Atlantic Ocean. They landed in South America and gave way to a new line of prehistoric crocodiles.
That’s the main conclusion of a new study describing a seven-million-year-old crocodile skull discovered in Libya. Paleontologists performed CT scans on the fossilized skull and determined that the ancient species is very similar to the American crocodiles that still live today. This party hints at a transatlantic voyage to South America.
The findings were published Thursday in the journal. Scientific reports. He argues that the archaic species in question, Crocodylus checchiai, It is a link between Nile crocodiles and four species of American crocodiles.
The study’s lead author, Massimo Delfino, is a paleontologist at the University of Turin and specializes in birds and reptiles. He says that the new analysis of C. checchiai It places it right between African and American species.
Because the oldest American crocodile species is approximately 5 million years old, discovered in Venezuela, these Libyan fossils fill a gap between two reptilian worlds. After finishing the trip, crocodiles eventually became the species we know today, spreading throughout the Americas, the study suggests.
“We found a species that could reasonably be the origin of American crocodiles,” says Delfino Reverse.
Transatlantic voyage – Beyond connecting these moments in the evolution of crocodiles, the new finding suggests a geographical bridge: at some point, crocodiles like C. checchiai discovered how to get from Africa to the Americas.
Marine crocodiles can sound surprising, especially when traveling at that distance. But Delfino points out that modern marine crocodiles can travel hundreds of miles in just one month. The special glands help them excrete excess salt water, just like the ancient species of the genus. Crocodylus.
Furthermore, this is not the first time that researchers theorize that ancient animals made such a journey. Researchers believe that 30 million years ago, monkeys made the same journey, with the help of rafts made of vegetation. A study published in April found that two monkey lineages from Africa gave way to New World monkeys in South America. That means the monkeys somehow rafted more than twice.
“If you think the monkey can cross the Atlantic Ocean, it is very likely much easier to accept that the crocodile can do it,” says Delfino.
Today, there are four living species of true crocodiles in the Americas. Evidently, “the colonizers of America found the land warm enough to survive and for diversity,” says Delfino.
“If you think the monkey can cross the Atlantic Ocean, it is very likely much easier to accept that the crocodile can do it.”
Given what we know about marine crocodiles, you may have only taken the crocodiles A few months to make the journey Marine crocodiles are also known to eat sea turtles, providing another clue to how ancient crocodiles fed while sailing in the Atlantic.
Old bones While the discovery of this species as a bridge between continents and species is new, fossilized bones were first discovered in 1938.
For almost a century, ancient fossils of crocodile skulls lurked, most recently housed at the Sapienza University Museum of Earth Sciences in Rome.
“This fossil is twice as old,” says Delfino: It has been around for millions of years, and has also been known to humans for decades.
The fact that this “forgotten skull” may yield new discoveries speaks to the importance of museum collections, says Delfino. Especially at a time when ambitious research trips are extremely difficult, there are discoveries awaiting paleontologists in museum collections.
“We must not forget that there are treasures in museums,” says Delfino.
Summary: The molecular and morphological phylogenies coincide in indicating that the aforementioned African lineages Crocodylus niloticus are the sister taxa of the four neotropical crocodiles (Crocodylus intermedius, C. moreleti, C. acutus and C. rhombifer), which implies a transoceanic dispersion from Africa to America. Until now, the fossil record did not help to identify a possible African precursor of the neotropical species, but, curiously, the oldest remains referred to the Africans. C. niloticus They are of Quaternary age, while the oldest American fossils of Crocodylus are older, dating from the early Pliocene, suggesting that another species might be involved. We also redescribed, also thanks to CT images, the only well-preserved topotypic skull of Crocodylus checchiai Maccagno, 1947 from the African Miocene (Messinian) site of As Sahabi in Libya. As previously suggested based on material from the Late Miocene of Tanzania, C. checchiai It is a valid and diagnosable species. According to our phylogenetic analyzes, C. checchiai It is related to neotropical taxa and could even be located at the base of its radiation, representing the missing link between the lineages of Africa and America.
