In 1906, the Royal Navy launched the HMS Dreadnought, a battleship outfitted with such destructive power that most heavily armored battleships to come after it were simply called “dreadnoughts.” Unearthing possibly the largest land animal to ever amble over the Earth, paleontologists might have just created a similar situation for all other large dinosaurs: Meet Dreadnoughtus schrani.
Discovered in southern Patagonia in Argentina, this new titanosaur — a group of incredibly massive sauropod dinosaur species — has the distinction of being one of the most complete ever discovered, published today in Scientific Reports. One of the two Dreadnoughtus specimens detailed in the study is nearly 50 percent complete. For comparison, the next most complete titanosaur find, Futalognkosaurus dukei, was only 15 percent complete. Based on the bones, the research team, led by discoverer Dr. Kenneth Lacovara, an associate professor in Drexel University’s College of Arts and Sciences, estimates that Dreadnoughtus was 85 feet (26 m) long and weighed about 65 tons (59,300 kg). That’s a Boeing 737 longer than a basketball court.
“It is by far the best example we have of any of the most giant creatures to ever walk the planet,” said Lacovara in a press release.
The inevitable question becomes whether or not Dreadnoughtus was the largest dinosaur ever. Well, It depends. For example, another titanosaur, Argentinosaurus, was probably as big and might even have been more massive. However, that comparison is based on a far-less complete skeleton.
To calculate the mass of an extinct animal, we extrapolate from the size of what they leave behind — their bones. Specifically, we use the size of the femur, an upper-limb bone, and some equations we have found to apply to large animals generally to get an estimate. And because the Dreadnoughtus specimen was so complete, its 65-ton estimate outweighs possibly larger weights from titanosaurs with less evidence supporting their size. In short, Dreadnoughtus has the largest calculable weight of any known land animal, and we have the evidence to back it up.
And this specimen was still growing.
Lacovara’s team isn’t exactly sure how the two Dreadnoughtus specimens met their end — though they didn’t have any bone markings indicating large predators chewing them up — but they know these gigantic longnecks weren’t at the end of their lives. They were still growing fast. In megafauna like these, the immense weight they lug around leaves an indelible impression on the bones. The Dreadnoughtus‘ shoulder bones were not fused and microscopic analysis did not find any cellular structures associated with mature animals. Possibly the largest land animal ever could have been even bigger. But as always, more research is needed and more dirt needs to be dug.
If you want to check out Dreadnoughtus‘ bones for yourself, the research team has done something rather awesome — they laser-scanned all the bones into a database that anyone can explore (provided you have Adobe Reader). On top of that, the study itself is open-access, so feel free to dig into these dinos yourself.
You can watch a video summary of the Dreadnoughtus findings below:
What do you call a dinosaur that doesn’t fear people? A dread-nought-us! Sorry… sorry.
IMAGES: Artist’s representation: Jennifer Hall, Mass comparison: Lacovara Lab, Drexel University, Drexel University