Scientists discover skull and neck fossils of titanosaur
PITTSBURGH – Perhaps the most complete skull and neck fossil of a titanosaur – the family of long-necked, long-tailed dinosaurs that were the largest creatures ever to walk on Earth – has been discovered with important new findings detailed online Tuesday in the journal Plos One.
The fossils of Sarmientosaur musacchioi, discovered by National University of Patagonia paleontologist Ruben D.F. Martinez, indicate a somewhat small titanosaur that would measure 40 to 55 feet and 10 tons (the size of two large elephants). It was discovered in the Patagonia region of Argentina.
Palenotologist Matt Lamanna of the Carnegie Museum of Natural History was a key member of the research team to analyze the skull. He, Martinez and Lawrence Witmer of Ohio University Heritage College of Osteopathic Medicine, announced the discovery Tuesday during a news conference at the natural history museum.
Martinez, a doctor of paleontology, said such discoveries “happen once in a lifetime.” “That’s why we studied the fossils so thoroughly, to learn as much about this amazing animal as we could.”
Titanosaurs are plant-eaters and represent that type of dinosaur most people think about when the term arises. They have small heads at the end of an extended neck, with a massive body, trunk-like legs, and a long powerful tail.
“Comprising more than 60 named species, titanosaurs lived on every continent and ranged in size from the weight of a cow to at least the weight of the biggest sperm whale, a museum release states. The Sarmientosaur lived about 95 million years ago and despite its enormity was only half the size of the largest titanosaurs.
But knowledge of titanosaurs has been limited because of the 60 titanosaurs that have been discovered, there are only three that included relatively complete skulls – that is, until Sarmientosaurus. Scientific excitement includes the ability to analyze the full brain casing, which provides new details about the exact size and function.
It had large eyeballs indicating good vision, along with an inner ear tuned to hear low-frequency airborne sounds as compared with other titanosaurs.
The balance organ of the inner ear indicates that the dinosaur probably held its head with the snout facing downward, which may in turn suggest that it fed primarily on low-growing plants on the ground rather than browsing through trees for food.
”The skull is beautifully preserved, which meant that we could tease out a ton of information,“ Witmer said. ”It was really exciting for us to work through the CT scan data because it gave us a glimpse into the biology and lifestyle of this animal like we rarely get with dinosaurs.“
The dinosaur’s genus was named after the town of Sarmiento in the Chubut Provision of Argentina, which is close to the discovery site, while the species name (musacchioi) is named in honor of Eduardo Musacchio, a palentologist and professor who was a colleague of Martinez and killed in a plane crash.
Lamanna at the Carnegie Museum has been involved in the discovery of various notable titanosaurs, including Dreadnoughtus (42 tons and 85 feet long) and Notocolossus (66 tos and up to 92 feet long), both also discovered in Patagonia.