Sauroposeidon proteles (SAWR-o-po-SYE-don pro-TEL-ees)
is a one-of-a-kind dinosaur. In 1994, vertebrate paleontologist
Richard Cifelli and his team from the Sam Noble Oklahoma Museum
of Natural History at the University of Oklahoma found four vertebrae
of one of these dinosaurs in southeastern Oklahoma. Each vertebra
measures four feet or more in length. The bones were so enormous
that Cifelli himself was unsure what he had uncovered at first.
"I thought we had a petrified tree trunk," Cifelli said. "I just
could not get my mind around the size of these bones."
Once a closer look had confirmed that the find was, indeed, fossilized
bones, Cifelli knew he had something special. No neck bones of
this size had ever been found.
In the lab, the bones revealed more surprises. One of Cifelli's
graduate students named Matt Wedel, now a paleontologist at the
University of California at Merced, ran one of the vertebra through
a CT scanner—a high-tech x-ray machine that creates a three-dimensional
image of the inside of an object. The scans showed him that, despite
their size, the fossils are extremely delicate. The vertebrae are
full of air pockets surrounded by thin membranes of bone—in some
place the bone is no thicker than a fingernail. These holey bones
are very similar to those of modern birds. The air pockets make
the bones lighter, without making them any less strong.
Cifelli and Wedel named the new dinosaur Sauroposeidon proteles.
Poseidon was the Greek god of earthquakes, and certainly the earth
must have quaked under the feet of this mighty beast. "Proteles"
means "perfected before the end," because this enormous dinosaur
was one of the last and most specialized of its kind. It lived
during the Cretaceous Period, around 110 million years ago. Though
there were many long-necked dinosaurs in North America during the
earlier Jurassic Period, there were fewer and fewer in the Cretaceous,
and they finally disappeared around 100 million years ago. Sauroposeidon
was among the last and mightiest of a dying breed.
Sauroposeidon seems to be a relative of Brachiosaurus, and like
Brachiosaurus, probably held its neck upright like a giraffe, rather
than out in front of it like the Apatosaurus. Sauroposeidon would
have been much larger than Brachiosaurus, however. Cifelli and
Wedel believe Sauroposeidon would have been nearly 100 feet long
and stood some 60 feet tall. It could have stood flat-footed and
looked into a sixth story window. Sauroposeidon is recognized by
the Guinness Book of World Records as the world's tallest dinosaur.
Despite several return trips to the site of the initial find to
search, no additional fossils of Sauroposeidon have been uncovered.
"The chances of finding more are remote," admitted Cifelli. Compared
to the light-weight neck bones, most of the dinosaur's other bones
would have been very large and heavy. If the skeleton had still
been all together when it was fossilized, the team would have found
other bones nearby. It is likely that the neck bones were moved—by
water or predators, for example—away from the rest of the dinosaur's
body. There is no way of knowing where to look.
Nevertheless, visitors to the Sam Noble Oklahoma Museum of Natural
History need now look no further than the museum's Great Hall to
get a glimpse of this record-setting dinosaur. A reconstruction
of the forty-foot neck and head of Sauroposeidon can be seen peeking
out into the Great Hall from the museum's new Orientation Gallery,
which will open March 29, 2009.