7-Million-Year-Old Fossil Found in Peru Shed Light on the Marine Origins of Modern Crocodiles

Archaeologists in Peru found some jaw and skull remains of a prehistoric animal that probably crossed the Atlantic Ocean to the coast of South America. Metro reported that this 7-million-year-old fossil could shed new light on the origins of the modern crocodiles and give more clues to their evolution.

The prehistoric fossil has given an insight into how all freshwater crocodiles in Peru first came to land from the sea. After many years of excavation, researcher Rodolfo Salas and his team collected partial skeletons from the species.

Collecting Ancient Crocodile Fossils

Salas and his team had collected partial skeletons in recent years after finding a jawbone in the Sacaco desert in Peru in 2020. That is when they understood that the animal evolved after living in saltwater.

The team named the species Sacacosuchus cordovai and estimated it to be at least 13 feet (4 meters). Salas said the new species could have lived in the Sacaco site about 7 million years ago.

"We have concluded ... that all marine crocodiles were animals with long and thin faces, and that there were two morphotypes," Reuters quoted Salas. "One that fed almost exclusively on fish and another that had a much more general diet."

They published their study, titled "Miocene Fossils From the Southeastern Pacific Shed Light on the Last Radiation of Marine Crocodylians," in the British scientific journal Proceedings of The Royal Society B.

The site is known for being home to various prehistoric skeletons of animals that have been found before. Experts say that the desert was a deep seabed where whales, giant sharks, crocodiles, and other marine species once lived.

In March, Salas and a team of paleontologists found a skull fossil of a 30-foot-long (12-meter-long) sea monster estimated to have lived 36 million years ago in the ancient ocean.

Modern Crocodiles Evolving Fast

Crocodiles may look like they still belong to prehistoric times, but appearances can be deceiving. A 2021 study suggests that crocodiles are not holdovers that went unchanged since the Jurassic period, Smithsonian Magazine reported. Instead, they are a great variety of families that have been around for 235 million years and continue to evolve even faster than they have in their history.

The study, titled "Complex Macroevolutionary Dynamics Underly the Evolution of the Crocodyliform Skull," published in Proceedings of The Royal Society B, compared three-dimensional models of crocodiles in tracking anatomical landmarks on their skulls over time.

Researchers from University College London, led by anatomist Ryan Felice, found that modern crocodile species in Australia, Southeast Asia, and Indo-Pacific are evolving faster despite looking still like aquatic antiques.

They noted that modern crocodiles look similar because they are evolving the same skull shapes repeatedly through time and not because they are conserving ancient traits.

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