`Biggest` dinosaur bones unveiled in US

The bones belong to the sauropod dinosaur Alamosaurus sanjuanensis: A long-necked plant eater related to Diplodocus.

Updated: Dec 11, 2011, 15:49 PM IST

Washington: Paleontologists have discovered
what they claim are bones of the "biggest" dinosaur in the US.

A team from the Museum of Rockies in Montana State and
the State Museum of Pennsylvania has described two gigantic
vertebrae and a femur that it collected in New Mexico from
2003 to 2006 in a research report.

The bones belong to the sauropod dinosaur Alamosaurus sanjuanensis: A long-necked plant eater related to Diplodocus
which roamed what is now the southwestern region of the US and
Mexico about 69 million years ago.

In their report, the palaeontologists have written how
carrying the the vertebrae alone was a "killer" task taking up
an entire day because they carried them 1.2 miles through 100-
degree heat, a website reported.

Denver W Fowler at Montana State University, who led
the team, said: "Alamosaurus has been known for some time, its
remains were first described in 1922 from the Naashoibito beds
of New Mexico.

"Since then, more bones have been discovered in New
Mexico, Utah, some really nice material from Texas, and
Mexico, including a few partial skeletons."

He said the sheer size of the new bones had caught the
researchers by surprise, who had believed that a fully grown
Alamosaurus measured around 60 feet long and weighed about 30

The enormity of the new bones puts Alamosaurus in the
same size league as other giant sauropods from South America,
including Argentinosaurus which weighed about 70 tons, and is
widely considered to be the biggest dinosaur of all.

Dr Fowler said: "Over the past 20 years, Argentinean
and Brazilian paleontologists have been unearthing bigger and
bigger dinosaurs, putting the rest of the world in the shade.

"However, our new finds not only show that Alamosaurus is
newly recognised as the biggest dinosaur from North America,
but also that it was right up there with the biggest South
American species..."

He added: "We found a shed Tyrannosaurus tooth with
another Alamosaurus neck bone that we were excavating. The
Tyrannosaurus may have lost its tooth while feeding on an
Alamosaurus carcass."