title: Leonardo da Vinci: engineer, bioengineer, anatomist, and artist.
abstract: Leonardo da Vinci (1452-1519) enjoys a reputation as one of the most talented people of all time in the history of science and the arts. However, little attention has been given to his contributions to physiology. One of his main interests was engineering, and he was fascinated by structural problems and the flow patterns of liquids. He also produced a large number of ingenious designs for warfare and a variety of highly original flying machines. But of particular interest to us are his contributions to bioengineering and how he used his knowledge of basic physical principles to throw light on physiological function. For example, he produced new insights into the mechanics of breathing including the action of the ribs and diaphragm. He was the first person to understand the different roles of the internal and external intercostal muscles. He had novel ideas about the airways including the mode of airflow in them. He also worked on the cardiovascular system and had a special interest in the pulmonary circulation. But, interestingly, he was not able to completely divorce his views from those of Galen, in that although he could not see pores in the interventricular septum of the heart, one of his drawings included them. Leonardo was a talented anatomist who made many striking drawings of the human body. Finally, his reputation for many people is based on his paintings including the Mona Lisa that apparently attracts more viewers than any other painting in the world.
authors.affiliation: Department of Medicine, University of California, San Diego, La Jolla, California jwest@ucsd.edu.
authors.forename: John B
authors.initials: JB
authors.lastname: West
mesh_terms: D054814:Anatomists / Q000266:history*; D001154:Art / Q000266:history*; D057005:Bioengineering / Q000266:history*; D049668:History, 15th Century; D006801:Humans; D010827:Physiology
keywords: Galen; breathing mechanics; diaphragm; fluid flow; intercostal muscles