fossils

Skull of long-necked "Eeyore" dinosaur discovered

3986b46bb4f35aa1ff4d42167a12e0fc

Vasika
Udurawane

Writer
The long-necked, big-bodied sauropod dinosaurs are known in popular culture for their often immense size, with some being the biggest animals to have ever walked the Earth. Yet while the huge thighs and necks of these behemoths are well-known, very few are known for their skulls. With Sarmientosaurus though, we have an exception.

A new finding in Argentina’s Chubut Province will rewrite our understanding of some of the biggest animals to have existed. Named Sarmientosaurus musacchioi, this new dinosaur not only hung its head like a gigantic Eeyore but also has a rare claim to fame. It is one of the few titanosaur sauropods known from a complete skull. The animal was discovered in 1997 by paleontologist Ruben D.F. Martinez. The holotype (a term that means the original body parts or illustration of a new species), of course, was the skull, and it was connected to a series of neck vertebrae. Then in 2016, a team comprising Martinez himself, Matthew Lamanna, Fernando Emiliano Novas and colleagues described and named the creature.


The animal hails from the middle of the Cretaceous, roughly 95 million years ago, and comes from a famous site known as the Bajo Barreal Formation. Other sauropods have been found here as well, but a sauropod skull is a first from this formation. The genus name of the creature honors the nearby town of Sarmiento while the species name is an homage to the late Dr. Eduardo Musacchio. Martinez and team studied the skull thoroughly, even taking several CT scans and creating 3-D models of the creature’s head to properly delve into the animal’s braincase.


The animal’s brain was small in comparison to its body, but it had massive eyeballs and probably very sharp vision, a unique discovery among sauropods. It was also able to hear very low-pitched sounds, an attribute ascertained by studies of the creature’s inner ear structure. Because of the way the dinosaur hung its head, Martinez describes Sarmientosaurus as a massive Eeyore, the depressed donkey character from the Winnie-the-Pooh stories. It held its head at a low angle, just as the fictional character does. A sauropod skull is a rare and precious finding, but a complete skull that makes artistic restoration of the animal all the more simple is an absolute exception.


The sauropod dinosaurs are the gigantic, long-necked and long-tailed dinosaurs of popular culture. Through some famous examples like Brontosaurus and Brachiosaurus, they have entered the public consciousness as the biggest land animals to have ever walked the planet. Yet for the most part we know precious little about the skulls of these huge creatures. For one, the skulls are often very delicate and small in comparison to the rest of the animal’s body. This means that the skulls can easily break apart, even if the dinosaur is immense.


Sarmientosaurus belonged to a unique group of sauropods known as titanosaurs. They were common all over the world, and represented the most successful of all sauropod clades. During the Cretaceous, there were members living as far apart as Romania, Argentina, Egypt and New Mexico. Many of them were heavily armored, with huge bony plates and spikes running down their backs and shoulders. They were also much more robust and heavily built than other sauropods. Among their ranks were some real monsters. Some, like Argentinosaurus were among the biggest-ever dinosaurs, weighing in at a ground-shaking 80 tons. The newly discovered Sarmientosaurus though, was much smaller. It was 12 meters in length and weighed 10 tons – big by today’s standards but a small fry in front of the real behemoths of its time.


Original research was published on PLOS ONE

Image Credit: Joschua Knuppe

3986b46bb4f35aa1ff4d42167a12e0fc

Vasika
Udurawane

Writer


http://sulc.us/tnlej
http://www.eartharchives.org/articles/skull-of-long-necked-eeyore-dinosaur-discovered/