Jean Louis Rodolphe Agassiz FRS FRSE was a Swiss-born American biologist and geologist who is recognized as a scholar of Earth's natural history.
Spending his early life in Switzerland, he received a doctor of philosophy and a medical degree at Erlangen and Munich, respectively. After studying with Georges Cuvier and Alexander von Humboldt in Paris, Agassiz was appointed professor of natural history at the University of Neuchâtel. He emigrated to the United States in 1847 after he visited Harvard University. He went on to become professor of zoology and geology at Harvard, to head its Lawrence Scientific School, and to found its Museum of Comparative Zoology.
Agassiz is known for his regimen of observational data gathering and analysis. He made vast institutional and scientific contributions to zoology, geology, and related areas, including writing multivolume research books running to thousands of pages. He is particularly known for his contributions to ichthyological classification, including of extinct species such as megalodon, and to the study of geological history, including the founding of glaciology.