1804-1885

German zoologist who studied invertebrates and contributed much to the field of parasitology. One of the first important texts in comparative anatomy involved a collaboration between Siebold, who contributed the work on invertebrates, and Friedrich Hermann Stannius, who was responsible for the information on vertebrates. Based on factual observations, the text departed from earlier philosophical approaches. Siebold's work in parasitology involved the new idea that the stages in a parasite's life cycle alternate between hosts.