A Welcome To The Lady Stegosaurus

Dinosaurs have been extinct for about 65-million years, yet they remain a hot topic. A recently published paper based on new discoveries has shown that the Stegosaurus may have unique differences between the genders. Believe it or not, this find was made upon traveling to Montana to a ranch gully filled with fossils. The paper was written by 23-year old paleontology student, Evan Saitta, graduate student at Britain’s University of Bristol whose study appears in the journal PLOS ONE.

Stegosaurus a.k.a. The Spiny-Saurus

Stegosaurus‘ were omnivores and ate only plant matter. They had a long neck, a small head, and two rows of bony fins running along their spine. The ends of their tails were equipped with two rows of spikes that were used as a weapon in defense. Fully grown, a Stegosaurus could weigh up to 10 tons and grow to be 12-feet in height.

What’s really exciting about this is that this Stegosaurus finding is that it led us to learn more about sexing these dinosaurs. Researchers knew the difference in the Stegosaurus’ spiny plates, but up until recently, one Stegosaurus of each gender had never been found traveling with one another. Since the finding, there is an opportunity to study the differences and likeness of both, and further our knowledge of these giant lizards.

Stegosaurus walked this earth over 150-million years ago. This new paper indicates that the males had larger, wider plates on their back due to their investment in their ornamentation. The plates were used to attract the females; much like male bird plumage does today. It has been suggested by the paleontology student, Saitta, that females had the longer, sharper plates for defense. From past fossil finds, paleontologists knew that that two different types of scales could be found on the backs of these dinosaurs. The bony plates differ in width and height. Some are narrow and long, while others are short and wide. This finding of the two Stegosauruses at the same site led Saitta to the theory that its physical differences are due to sex. Once these fossils were found, it was hard to tell whether the difference was caused by age or something other than sex. Computerized tomography (CT) scans showed that the bone tissue had in fact stopped growing, which meant all of the samples were adults. This led to the observation by Saitta that perhaps the difference was gender.

Dinosaurs have fascinated everyone for years, hence why they continue to be studied long after they’re gone. This shows us that there still is so much more to learn. It’s been over 65-billion years since dinosaurs travelled the Earth, yet they continue to trump us. Opening this door to sexing the Stegosaurus is opening a door up to a room full of questions that we may or may not have the answers to 65-million years from now.

A road trip takes these adventurers through a world evincing visual qualities of the world around the time Stegosaurus roamed the earth: