Argentinosaurus Was Almost Half as Long as a Football Field

Argentinosaurus is believed to have measured between 95 and 100 feet long (30 meters), with some size estimates suggesting it could have reached lengths of up to 130 feet (40 meters). Its body mass is estimated to have been between 60 and 100 tons (99 to 110 metric tonnes).

Its long neck was supported by strong vertebrae, allowing it to reach vegetation high in the trees, while its massive body helped store energy and maintain balance.

The legs of Argentinosaurus were thick and column-like, built to support its enormous weight, and its tail may have acted as a counterbalance or even a defensive weapon against other giants.

Fossilized bones, including anterior dorsal vertebrae and limb bones, provide clues to its structure. But because complete skeletons have not been found, scientists rely on comparisons to other sauropods, such as Patagotitan, to reconstruct its anatomy.

Argentinosaurus was a prime example of how evolution scaled up herbivorous dinosaurs to dominate their ecosystems.

While Argentinosaurus huinculensis is the only officially recognized species in the genus, it belongs to a broader family of titanosaur species. These massive sauropods include related species such as Patagotitan and Futalognkosaurus, which shared similarities in size and structure.

Based on fossil records from the same region, there may have been minor variations among Argentinosaurus individuals due to geographic distribution or environmental factors.

Argentinosaurus is considered one of the largest of its kind. Its exact size remains a topic of debate among paleontologists who have differing opinions on the biggest dinosaur in history.

Differences in fossil preservation mean that many estimates are reconstructed using close relatives, allowing scientists to infer its dimensions and build with reasonable accuracy while still debating the largest dinosaur ever.

Argentinosaurus is thought to have been a social animal, living in herds to provide protection from predators such as Giganotosaurus. Moving in groups would have been advantageous for juveniles and smaller individuals, as the sheer size of adults likely deterred most attackers.

Herding behavior also allowed Argentinosaurus to efficiently strip large areas of vegetation, working together as they migrated through their environment. Herding may also have played a role in reproduction, with groups providing safer environments for nesting and raising young.

While direct evidence of nesting behavior is limited, comparisons to other sauropods suggest that Argentinosaurus likely laid eggs in communal nesting grounds, where group dynamics increased the survival chances of hatchlings.

As an herbivore, Argentinosaurus relied on a diet of plants, including ferns, cycads and conifer trees. Its long neck allowed it to graze on vegetation at various heights, giving it access to a wide range of food sources that smaller herbivores couldn't reach.

This feeding strategy helped Argentinosaurus maintain its massive size by consuming vast amounts of plant material daily.

Its peg-like teeth were designed for stripping leaves rather than chewing, meaning Argentinosaurus likely swallowed its food whole. Gastroliths — stones swallowed to aid digestion — may have helped break down tough plant fibers in its stomach.

This efficient feeding process supported the energy needs of such a colossal animal.

Argentinosaurus lived in what is now Patagonia, a region in South America that was vastly different 94 million years ago.

During the Late Cretaceous period, this area was a warm and humid environment with lush vegetation and numerous rivers. The abundant plant life provided ample food for Argentinosaurus and other herbivores.

This ecosystem was also home to formidable predators, such as Giganotosaurus, one of the largest carnivorous dinosaurs of the past.

Argentinosaurus likely shared its environment with some of the other largest sauropods and smaller herbivorous dinosaurs, creating a dynamic and competitive landscape. The presence of large predators and diverse prey shaped the balance of this ancient ecosystem.

Argentinosaurus began its life as a hatchling emerging from an egg no larger than a soccer ball, despite its eventual massive size.

Like other sauropods, it grew rapidly during its early years, possibly gaining several tons of weight annually. This rapid growth helped juveniles reduce their vulnerability to predators.

Reaching full maturity may have taken decades, with adult Argentinosauruses towering over their ecosystem as some of the largest creatures to have ever lived.

Their long lifespan — potentially up to 70 years — allowed them to dominate their environment for generations, with adults facing few threats due to their size.

Argentinosaurus' fossilized remains are critical to understanding the evolutionary history of giant dinosaurs. Fossils from Patagonia, discovered by paleontologists such as Bonaparte and Coria, have revealed invaluable information about its anatomy, behavior and ecosystem.

However, very few definitive remains of the species have been discovered, leaving many questions unanswered about the life and habits of Argentinosaurus.

We created this article with AI technology, then made sure it was fact-checked and edited by a HowStuffWorks editor.