After sifting through the sands in a forgotten part of Egypt, Penn researchers made an unexpectedly large find -- a new genus of dinosaur never found before.
The new dinosaur, named Paralititan stromeri, appears to be the second largest dinosaur known to man, coming in second only to Argentinosaurus, which currently holds the title of largest.
"This was an enormous beast by anyone's estimation," said Joshua Smith, the Penn doctoral student who discovered Paralititan.
The bones found by the team represent only a partial skeleton, and includ several vertebrae, dorsal ribs, both scapulae, both humeri and possible dermal armor.
The researchers estimate the large herbivore measured 80 to 100 feet long, and weighed between 60-70 tons, making Paralititan not only the second largest dinosaur, but also the heaviest.
Smith noted that researchers still need to take size variation into account when comparing dinosaurs.
"We don't know if we have a small Paralititan or a large Paralititan," he said. "We don't understand the size variation."
Fellow team member and Penn graduate student Matthew Lamanna said the new dinosaur fits the "classic image of a dinosaur." Paralititan is a sauropod, meaning it had a long neck and tail.
"It had a giraffe-like posture, but... with short front legs," Geology Professor Peter Dodson, another team member, added.
Lamanna warned, though, that "this is not just an overgrown lizard" unable to do much moving around.
"These were also animals fully capable of supporting their weight on land," he said.
The dinosaur died 94 million years ago in an area of Egypt called the Bahariya Oasis -- located about 180 miles southwest of Cairo. Bahariya, which is now part of the arid Sahara landscape, was composed of mangrove swamps almost identical to today's Florida Everglades.
It is rare to find such a large creature living in a coastal area such as the Bahariya Oasis. The name Paralititan is the Greek translation for "tidal giant".
Team member and Drexel University sedimentologist Kenneth Lacovara said that "water [in the tidal area] wasn't even covering this beast's calves."
The dinosaur's other name -- stromeri -- is in honor of German explorer Ernst Stromer, who discovered bones from other creatures and smaller dinosaurs at the Bahariya site in the early 1900's.
Stromer's finds were lost during World War II, however, when the Munich museum in which his finds were housed was destroyed during Allied bombings.
Among Stromer's finds were the bones of three other carnivorous dinosaurs, similar to the well-known Tyrannosaurus rex. Researchers did not understand how such top-tier carnivores could share one small coastal area -- until the discovery of Paralititan.
"We're starting to get a glimpse of what the bottom of this [food] pyramid was" in the Bahariya region, Smith said.
All of the researchers agreed that the find is important in understanding North Africa during the Late Cretaceous Period.
"It's more in terms of what the dinosaur can tell us about Bahariya 94 million years ago," Smith said.
Further research on Paralititan and the region could yield information, for example, about why the once lush mangrove forest is now part of an arid desert, and about climate change in general.
Team member and Penn graduate student Jennifer Smith compared studying the fossils of ancient creatures to being able to see the world as they did.
"Everyday you go out there you get a new pair of eyes," she said.
The team published their findings in the June 1 issue of the journal Science.
