The story of Pawpawsaurus
campbelli begins in the Early Cretaceous Period, around 97 to 100 million
years ago, when the North American continent was divided down its centre
by an interior seaway. Along the shores of this seaway, in the area
which is now North Central Texas, lived one of the most primitive known
species of nodosaurid dinosaurs - Pawpawsaurus. This and other
members of the nodosaurid group are characterized by their tough, flexible
armor, which served to help protect them from the powerful predators of
their Mesozoic world. The nodosaurs are a part of the dinosaur superfamily
Ankylosauria, which consists of nodosaurid, ankylosaurid and polacanthid
branches. Members of all three of these groups were well armored,
but as an additional form of defense, the ankylosaurids evolved large clubs
on the ends of their tails, which could be swung with great force.
The nodosaurids and polacanthids were the more primitive of the ankylosaurians,
and lacked tail clubs.
The skull of one of the Pawpawsauri was
preserved by the process of fossilization after being washed out into the
marine sediments of its coastal habitat. Many millions of years passed
by. The ocean gradually receded by hundreds of miles as the continent
underwent significant geological changes, and the interior seaway eventually
disappeared. Through the rest of the Cretaceous and then all of the
Cenozoic epochs, the skull of Pawpawsaurus lay encased in stone
beneath the Earth's surface. Eventually, the forces of erosion began
weathering away its rocky tomb, and the first rays of sunlight in some
970,000 centuries shone on the skull.
One day in May of 1992, I noticed a small
bit of fossil bone emerging from the surface of a shale/clay exposure known
as the Paw Paw Formation. I began carefully clearing away bits of
the crumbling rock, and soon found that I had discovered something very
unusual indeed - a fragmented but virtually complete dinosaur cranium!
I soon took the skull to the Shuler Museum of Paleontology at Southern
Methodist University (Dallas), where a detailed and lengthy study of the
specimen was undertaken. Months of careful cleaning were needed to
remove a thin layer of shale matrix, as well as an encrusting group of
oyster shells which had used the skull as a support structure as it lay
on the seabed prior to its burial in sediment.
Below is an array of buttons which will
take you to each of the various sections of the Pawpawsaurus web
The first section discusses the skull
which gave the species its name and scientific description. Section
two provides some examples of artists' conceptions of what Pawpawsaurus
may have looked like in life. The third section is about the realistic
cast replica that I personally produce of the skull for sale to museums,
universities and private collectors. Section four presents various
publications in which Pawpawsaurus has been featured, as well as
a downloadable version of Yuong-Nam Lee's research paper on the species.
The remaining two sections are dinosaur/palaeontology links, and natural
history museums with significant dinosaur exhibits.
copyright © C. Campbell's NATURAL
and other illustrations (where indicated) are © C. Campbell's NATURAL
photos and images are © their respective owners.