- Chinese Dinosaur - Psittacosaurus
- Early Cretaceous, Asia
There are 9 described species of Psittacosaurus. The name
is Greek meaning Parrot Lizard. They are predominantly found
in Asia. The holotype is housed in the American Museum of Natural
History #6254. It was discovered in 1922 by a Mongolian Chauffer
during the AMNH central Asiatic Expeditions led by Roy Chapman
Andrews. It was later described by Henry Fairfield Osborn and
was on display at AMNH for many years.
The specimen offered here may be P. sinensis because
the tibia is longer than the femur. In addition, the ischium
is distinctly longer than the femur. Based on the death
pose and position of the forearms and size of the eye orbs, I
personally believe the animal could have been a burrower and
may have died in its burrow. It has a similar pose to burrowing
dinosaurs I've seen such as a dinosaur known as Drinker. One
thing we know for sure...It's definitely dead and was covered
quickly after it died. The bones were not crushed nor were they
scavenged by anything other than insects. It is so rare to have
a complete dinosaur in such an articulated and interesing pose.
Although they have been studied extensively, scientists still
debate the classification. Based on general body proportions,
some place them in the primitive hypsilophodontid group of ornithopods,
a bipedal herbivore. Others argue they belong with the quadrapedal
ceratopsians based on a suite of characters present in the skulls
of all ceratopsians.
In 1924, Osborn suggested that the long lateral jugal horn,
projecting to the side of the skull, could be used for combat
between other Psittacosaurus by swinging it side to side. The
teeth of this one year old juvenile are ground down from feeding
on abrasive vegetation. This suggests that Psittacosaurus may
not have been cared for by parents at least in the form of being
fed regurgitated food.
This specimen also contains a number of gastroliths. As many
as 50 gastroliths have been found in some specimens. These gastroliths
were used in helping with grinding and breaking down the plant
material. The tooth pattern was that of a primitave ornithiscian
dinosaur. Modern ceratopsians would later have large batteries
of teeth eliminating the need for gastroliths.
It had a very small brain case so it had limited behavior
patterns when compared with a mammal of the same size. Based
on the size of the eye orb, the animal probably had good vision.
Based on the proportions of the forearms to hindlimbs, it's
possible that the forearms were used for locomotion as well as
having a limited ability to grasp vegetation.
Reference Encyclopedia of Dinosaurs by Donald F. Glut,
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