ABSTRACT Since their first discovery back in the 1800's, dinosaurs have always been classified as dimwitted and sluggish beasts by the general public. As time has passed progress has been made that shows dinosaurs as active, intelligent, and even caring animals. Yet many of the larger herbivores like the Sauropods and Ceratopsians are viewed as roaming cows. Recently, paleontological studies have been focusing on the movement of some of the larger specimens through studies on their limbs and body mass. Yet, I believe that another character that should be studied in relation to a dinosaurs mobility is the spinal column. For my thesis project I have examined the vertebrae column of a Leptoceratops Gracilis in the hopes that the analyzes shows that Leptoceratops, along with other Ceratopsians, were very flexible animals.
The specimen used for this project is a replica of a well preserved and fairly complete Leptoceratops Gracilis vertebrae column found in the Scollard Formation of Alberta, Canada and on loan to the Raymond M. Alf Museum of Paleontology. The initial examination of the Leptoceratops vertebrae involved taking various pictures and measurements of the individual vertebrae with a focus on the Zygapophysis and Neural Spine because these are the characteristics of the vertebrae that relate to flexibility. In order to analyze the flexibility of the vertebrae two different approaches were used. The first was the anatomical comparison of the Zygapophysis and Neural Spine of the Leptoceratops vertebrae to the flexible vertebrae of a Cheetah and the non-flexible vertebrae of a Rhinoceros. Along with a comparison to one of the Dinosaurs most recent relatives, an Alligator. This was done to see if the Leptoceratops vertebrae were physically similar to a flexible vertebrae or non-flexible vertebrae. The second method of analyzes involved using the computer program ImageJ to measure the angle of the Zygapophysis and then graph the numerical data in an excel spreadsheet to view how the Zygapophysis angle changed down the vertebrae column. A final step was to then compare the Leptoceratops vertebrae to another notable member of the Ceratopsian family, Triceratops. From the results of the data I was able to conclude that Leptoceratops did possess a very flexible spinal column. This was supported by the Leptoceratops vertebrae containing many physical characteristics similar to the flexible Cheetah vertebrae, such as fairly rounded and angled Zygapophysis for horizontal movement of the spine, and Neural Spines that were spread apart for increased vertical movement. The anatomical data was further supported by the excel sheets showing a trend of the Zygapophysis angles and distance between them increasing near the neck and tail regions of the spine for better movement of the neck and tail. When compared to the Triceratops vertebrae there were also shared physical characteristics and trends in the excel graphs that could support that even such a large Ceratopsian dinosaur as Triceratops was also a flexible animal. In order to expand on this project more complete vertebrae specimens of both Ceratopsians and present day animals need to be analyzed and added to the collective pool of data along with more features studied on the individual vertebrae besides just the Zygapophysis and Neural Spine to achieve a more precise conclusion on the spine flexibility of Ceratopsians.
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