94 million years old herbivore dinosaur fossil found in Argentina, tells about evolutionary secret links

Fossils are vital clues about the Earth's ancient past, they are a means of link in the form of preserved remains of organisms that lived millions of years ago. They help scientists understand how life evolved, how the living conditions changed over time. These fossils also give a timeline of Earth’s geological and biological history, by giving a window into prehistoric life and environments.

Recently, a newly discovered 94 million-year-old dinosaur fossil in Argentina is helping scientists put together the puzzle of how some of the largest animals to ever walk the Earth evolved. Found in the Neuquén Province, a region already famous for significant fossil finds, this newly named species, Cienciargentina sanchezi , gives new information about the early days of the rebbachisaurid family, a group of long-necked herbivores within the larger diplodocoid family.


Where have these fossils been found?

These fossils were found in the Huincul Formation and date back approximately 94 million years to the Late Cretaceous period . This makes Cienciargentina sanchezi the oldest known rebbachisaurid on record, according to a study recently published in Cretaceous Research. The discovery gives a key evolutionary link that helps explain how sauropods adapted to their environment, diversified, and survived through major environmental changes. The bones are also important anatomical clues that tell how these creatures lived, moved, and even how they might have defended themselves.



This fossil belongs to the family of long-necked dinosaurs

The area where these fossil remains were found is sediment-rich, where several major dinosaur discoveries have been made over the years. Cienciargentina sanchezi has been one of the major discoveries due to its skeletal features, which clearly make it a primitive member of the rebbachisaurid group. These dinosaurs are a subset of diplodocoids, famous for their long necks, plant-based diet, and large size.

“This new species is added to the list of rebbachisaurid sauropods documented in the Huincul Formation,” paleontologist Leonardo Salgado said to Cretaceous Research. He and co-author Simón also noted that unique features in the vertebrae confirmed the dinosaur’s place in the early stages of rebbachisaurid evolution.

The fossils showed long, flexible necks and strong, weight-bearing limbs, classic traits of sauropods. The vertebrae in particular showed distinct shapes that set this dinosaur apart. Some were concave on both sides, while others were slightly concave at one end and convex at the other, which is a sign of transitional evolutionary form.

A window into Sauropod evolution and ecology


One of the most significant anatomical discoveries involved the cervical vertebrae, which lacked the epipophyses typically seen in other diplodocoids. The dorsal vertebrae also showed a mix of primitive and more advanced features, making them crucial for tracing the evolutionary path of these animals.


“The first South American rebbachisaurid sauropods were recognized upon the basis of materials from the surroundings of Villa El Chocón, from the Candeleros and Huincul Formations,” Salgado noted, putting this new discovery into broader scientific context.

The environment where Cienciargentina sanchezi lived was a fertile floodplain during the Late Cretaceous, which was ideal for large herbivores. Paleontologists believe shifting vegetation, terrain, and climate may have lead to new evolutionary adaptations among sauropods.


Photo Credits: Animals HQ