The Idea of an Essay, Volume 2

132 and Physiology at the University of Wyoming. The authors present data found by their calculations in the form of charts and graphs that compare the blood pressure and wall thickness of the ventricles to the mass and length of the giraffe’s body and neck. The data was retrieved from previously derived allometric equations. They also discuss three hypothesis for why giraffes have high blood pressure. Mitchel and Skinner give explanations and average quantitative data of the cardiac hypertrophy, stroke volume, heart rate, and cardiac output that occurs in adult giraffes. This is invaluable information about the overall cardiovascular system in giraffes. This accurate, well written, scientific article will help me explain the anatomy of the circulatory system in giraffes and how the circulatory system functions uniquely with the giraffe’s long neck. Mitchell, G., Van Sittert, S., & Skinner, J. (2009). The structure and function of giraffe jugular vein valves. South African Journal of Wildlife Research, 39(2), 175-180. This article was written by Graham Mitchel, Sybrand J. Van Sittert, and John D. Skinner. The authors are either faculty on the veterinarian staff or work in the Zoology and Physiology Department of the University of Wyoming or the University of Pretoria. This article discusses the anatomy of the jugular vein in the giraffe. They conducted an experiment which consisted of the dissection of the jugular veins of twenty five juvenile to adult giraffes and five fetal giraffes. Mitchel, Van Sittert, and Skinner discuss the results and come to a conclusion about the importance of location and anatomy of the valves located in the jugular vein in giraffes. The authors discuss the problem of blood re-entering the cranial veins and how it is prevented. They explain the anatomy of the uniquely designed jugular vein and valve placement that make the giraffe able to bend without blood regurgitating into the brain. This well-developed experiment and accurate, scholarly information will be helpful in explaining the anatomy of