Ladies and gentlemen, meet Dreadnoughtus schrani, a newfound giant which—thanks to an amazing skeleton—can help us better understand some of the biggest dinosaurs that ever lived.
The species’ discovery was recently announced by an international fossil-hunting team, which excavated two specimens—including one that was unusually complete. A resident of modern-day Patagonia, this animal was roughly 86 feet in length and weighed an estimated 65 tons. At that size, Dreadnoughtus likely had few natural enemies when fully grown. Appropriately, therefore, its genus name literally means “fears nothing.”
Extra-large dinosaurs are nothing new in South America. Earlier this year, an eight-foot upper arm bone belonging to some huge herbivore was spotted in the vicinity of La Flecha, Argentina. Also, nearly man-sized backbones from a colossal creature called Argentinosaurus have been popping up since the 1980s.
Argentinosaurus and Dreadnoughtus are both classified as “titanosaurs”: a group of long-necked plant-eaters which started evolving during the early Cretaceous period around 100 million years ago. “Titanosaurs are… [remarkable] dinosaurs,” says Carnegie Museum of Natural History paleontologist Matthew Lamanna, “with species ranging from the weight of a cow to the weight of a sperm whale or more.”
Yet, larger titanosaur varieties usually haven’t been well-represented in the fossil record. Instead, amazing dinos like Argentinosaurus are largely known from scrappy material and isolated fragments.
But what makes the recent Dreadnoughtus discovery so exciting is the fact that nearly half (43%) of one skeleton has been recovered. For experts, this presents some exciting research possibilities.
Weighing a dinosaur is no simple task. Reimagining muscle mass is particularly tricky: when you’ve only got some skeletal remains to work with, it’s sometimes difficult to assess how slender or bulky their owner was.
However, limb anatomy can help point us in the right direction, especially when dealing with four-legged creatures like Dreadnoughtus. This new skeleton includes a humerus (“funny bone”) and femur (“thigh bone”), allowing paleontologists to take critical measurements designed to help ascertain how much heft these bones supported in everyday life. Therefore, Dreadnoughtus’ weight is, theoretically, far more calculable than that of most plus-sized titanosaurs.
It’s far too early to say. Ultimately, we may never know for sure. As mentioned earlier, dinosaurian behemoths don’t tend to fossilize very completely. Ergo, adequate length and mass measurements are often impossible.
Consider, for example, a mysterious species called Amphicoelias altus. To date, this beast’s existence is evidenced by a single vertebrae, which went missing after its discovery and remains unaccounted for. By comparing the fossil’s size to that of a corresponding bone in its smaller relative Diplodocus, some researchers have claimed that Amphicoelias could’ve been over 190 feet long! However, in the absence of any complete Amphicoelias skeletons, we can neither confirm nor deny these speculations or start comparing it with other jumbo dinos.
Nevertheless, one thing is quite certain: in their heyday, Dreadnoughtus and its kin must’ve been a spectacular sight to see.