Largest dinosaur species ever discovered crammed into American Museum of Natural History

By Joel Hruska 

Yesterday, the American Museum of Natural History opened the biggest dinosaur exhibit in its history, or at least the largest exhibit of any single dinosaur. The museum is showing the largest Titanosaur ever discovered. The bones were found in 2014 and the species is new enough that we don’t even have a formal name for it yet. Like the previous record-holder, Argentinosaurus, the as-yet-unnamed 122-foot Titanosaur was found in Argentina. A visual comparison of how various Titanosaurs compare to a human is below:

Titanosaurs, as the name suggests, are some of the very largest and heaviest dinosaurs to ever walk the Earth. They were sauropods, a type of dinosaur characterized by long necks, relatively small heads, and four thick legs that are more reminiscent of Grecian pillars than ordinary bones. The femur of this particular Titanosaur, for example, measured more than eight feet long. This particular specimen was an estimated 121 feet long and weighed in at 70 short tons (63 metric tons). That’s big, even by dinosaur standards, but scientists have determined that this dinosaur was only a juvenile.

This particular sauropod had pointier teeth than you might expect on a herbivore, according to Ars Technica, and scientists think it likely fed like a huge lawn mower — take a step, sweep the area in front of you for plant matter, swallow (without chewing), step, and sweep forward again. One of the misconceptions about sauropods in general is that they held their heads high, but their necks wouldn’t have been flexible enough to permit it in animals of this size. Titanosaurs are thought to have lived in herds for mutual defense and protection. The sheer size of a Titanosaur would have been its own defense — even Tyrannosaurus Rex, one of the largest predator dinosaurs (at least on land), would’ve weighed a fraction of a full-grown Titanosaur.

The new Titanosaur is thought to be ~10% larger than the Titanosaur Argentinosaurus, which was discovered in 1991. We only have a partial skeleton of that dinosaur, but scientists have done some interesting work on estimating how it walked and what its gait looked like. A 2013 digital reconstruction of the creature based on a musculoskeletal analysis (the first ever performed on this type of dinosaur) produced a video that makes the massive beast look almost dainty.

The maximum speed of Argentinosaurus was 5mph according to the reconstruction — not bad for a creature thought to weigh 80 tons (73 short tons). These sauropods are thought to have survived up to the Cretaceous–Paleogene extinction event, but were wiped out, along with the other non-avian dinosaurs, when the meteor hit.