It’s a species that is so new, it hasn’t been formally named by the paleontologists who unearthed it, according to the museum.
This enormous herbivore belongs to a group known as titanosaurs, paleontologists say. It tipped the scales at about 70 tons and lived in Patagonia around 100 million to 95 million years ago, in the late Cretaceous.
Excavated in the Patagonian desert of Argentina by researchers from the Museo Paleontologico Egidio Feruglio (MPEF), the team was led by José Luis Carballido and Diego Pol. One 8-foot long femur (thigh bone) discovered at the site is on temporary view with the titanosaur, along with three other massive bones.
The team has excavated over 200 bones, which represent 70 percent of the skeleton, Ars Technica reports. Remarkably, the skeleton displayed at the AMNH is made of lightweight fiberglass casts, which makes sense because the fossilized bones are extremely heavy and too much to support. Just the femur by itself weighs roughly 500kg.
The paleontologists say that this specimen isn’t a mature adult — some bones in titanosaurs fuse once growth stops, and that didn’t happen in this creature’s case. Researchers say they will tally up features on certain bones and will eventually be able to estimate the dinosaur’s actual age.
Things were smoothed right along by the partnership between the two museums and the fact that Pol received his Ph.D at the natural history museum.
The Titanosaur, currently exhibited in the Wallach Orientation Center on the AMNH’s fourth floor, replaced a fleshed-out and life-sized (although tiny by comparison) model of a young Barosaurus since the museum completed the fourth floor in June 1996, the AMNH reports.
The new inhabitant, however, is so big it touches the gallery’s 19-foot-high ceilings, and its head and neck poke out of the gallery and greet people coming out of the elevators.
How was this dinosaur discovered?
By happenstance, a farmer was searching his land in 2012 for a lost sheep, whom he found perched on a rather unusual-looking rocky ledge, The Guardian reports. Dinosaur finds are common in this area and the outcrop was huge, so the farmer wondered if this could be a fossil bone. He contacted the scientists, and when they determined this was, in fact, an eight-foot thigh bone of a dinosaur, life on the quiet farm definitely got busier. It suddenly became the most important dinosaur dig site in more than 100 years.
Then came an international team of biologists, a BBC film crew, aforementioned paleontologists, Hollywood model makers. Some 40,000 hours of work went into excavating the giant dinosaur, with spectacular results. Not only is this huge herbivore a new species, but it is the largest dinosaur ever to be discovered.
And there was even more good news: The team discovered that seven of these animals died in the exact same spot, on at least three different occasions, about 101.6 million years ago.
This newly discovered titanosaur is in the sauropod group, which included smaller sauropods like the well-known diplodocids and brachiosauridae. Titanosaurs, however, became truly gigantic and shook the ground they walked on, The Guardian notes. Fossils of these magnificent creatures are found worldwide, but South America is especially renowned for their fossils. Giants such as Puertasaurus and Argentinosaurus have been discovered there.
There was also plenty of evidence to suggest that these gentle giants dealt with large predators in their midst. At least 80 huge serrated carnivore teeth from an unknown dinosaur were strewn about the site, an indication that these peaceful herbivores may have met a bloody death.
Estimating the size of one of these massive beasts can be problematic. This was the case for Argentinosaurus, previously the biggest dinosaur, where estimates were based on fewer than 20 bones. For Puertasaurus, estimates were based on only four vertebrae.
What makes this newly discovered titanosaur different is that most of the skeleton has been unearthed — some 223 bones from the seven individuals. From this evidence, Pol and his team have used several methods to derive a reliable estimate of the creature’s size. By doing this, they were able to show that this dinosaur was 37 meters (a hair under 122 feet) and weighed 70 metric tons. This means it was the largest animal to ever walk the Earth.
“For a long time, we’ve known that animals may have approached this size, but they were largely just quite fragmentary remains, and we couldn’t get a really good look at just how immense these creatures were,” museum curator Dr. Mark Norell told PBS NewsHour. “This titanosaur specimen is a really important specimen in the great scheme of paleontology.”
So how did these massive creatures walk?
It helps to have legs like specially-adapted tree trunks. Because they were so big, these dinosaurs likely used the heavy musculature that worked like a buttress running from their thighs to about halfway down their tails. This helped them gain momentum for walking. And with all that weight comes the possibility of stresses and fractures, but these huge dinosaurs dealt with that by evolving reduced toes in their forelimbs. This forced them to walk on stumps of reduced metacarpal bones that were horseshoe-shaped, meaning that they walked on tiptoes supported by fleshy pads that cushioned the impact as they walked, The Guardian notes.
This titanosaur is the best preserved specimen “of this size that’s ever been found,” Norell said, per PBS.
“It gives us our first good, real picture about how we found them, about how big they were, about how tall they were,” he said. “And I think that for years to come, international groups of scientists will study this specimen.”
The discovery and mounting of this amazing dinosaur has presented monumental gains for modern paleontology, and new technologies have provided paleontologists with “an entirely new tool kit” to learn more about the biological characteristics of dinosaurs, including age, speed, weight, diet, color, and brain size, Norell said.
Titanosaurs walked with a commanding grace in their prehistoric world. Now, they engage our imagination and march through our minds.
