The Dutch natural scientist Jan Swammerdam (1637-1680) was a founder of comparative anatomy and entomology and was very skillful in the art of microdissection.

Jan Swammerdam was born on Feb. 12, 1637, in Amsterdam. His father, a prosperous apothecary, had collected a museum of curiosities. Jan soon developed a passion for natural history, in particular for the study of insects. His collection of insects, begun in his youth, eventually included some 3,000 species. At the age of 24 he went to Leiden to study medicine, where he graduated in 1667. His graduation thesis included the observation that the lung of a newborn mammal sinks in water but floats once the animal has breathed. Much to his father's displeasure, Swammerdam did not practice medicine but continued his microdissections of insects.

Swammerdam designed a simple dissecting microscope that had two arms: one for holding the object and the other for the lens; the arms had coarse and fine adjustments. He used very fine scissors for dissection and capillary tubes of glass for inflating or injecting blood vessels. He was one of the first to dissect under water and to remove fat by organic solvents. In 1669 he published his "General account of bloodless animalculae," a history of insects which dealt with their modes of transformation and development.

His interest in religion led Swammerdam to meet the Flemish mystic Antoinette Bourignon in 1673, who had a profound influence on his life. At this time he was engaged in a study of the life history of the mayfly which was, to Antoinette Bourignon, a "little beast which lives for only a single day, and throughout that time endures many miseries." She reluctantly allowed Swammerdam to publish his studies in 1675 (Emphemerae vita) on condition that he would study religion in the future. The book contains many remarkable pieces of minute anatomy, but these were diluted by allusions to the Bible and the development of an ethical system. During the remainder of his life he sufferred from periods of depression, during which he destroyed much of his work. He died on Feb. 17, 1680.

Swammerdam left many manuscripts which Hermann Boerhaave published in 1737 in two volumes called Biblia naturae (Bible of Nature). This book, which contained work done mainly between 1668 and 1675, is the finest collection of microscopical observations ever produced by one worker, and some of the figures have never been excelled. The book is the foundation of our modern knowledge of the structure, metamorphosis, and classification of insects. It also includes detailed observations on the Crustacea and Mollusca and on the life history of the frog.

Perhaps the most complete study is that on the honeybee, which is illustrated by beautiful drawings. In his studies on the frog, Swammerdam used a nerve-muscle preparation and invented a form of plethysmograph. He established that when the nerve was mechanically stimulated the muscle contracted, and he contradicted the idea, accepted in his time, that when a muscle contracted it increased in volume due to the passage of liquid from nerve to muscle.

Further Reading

• Abraham Schierbeek, Jan Swammerdam (trans. 1967), is the only modern biography. For Swammerdam's place in the history of biology, the student can consult Charles Singer, A History of Biology to about the Year 1900 (1931; 3d ed. 1959); F. J. Cole, A History of Comparative Anatomy from Aristotle to the Eighteenth Century (1944); and M. J. Sirks and Conway Zirkle, The Evolution of Biology (1964).