Louis Agassiz (full name Jean Louis Rodolphe Agassiz) was a leading naturalist of the nineteenth century. He is best remembered for his studies of fish fossils and for his opposition to Charles Darwin's theory of evolution.

The son of a minister, Agassiz was born May 28, 1807 in Switzerland. He attended the universities of Switzerland and Germany where he studied with the biologists Lorenz Oken and Ignaz Döllinger, who were followers of Naturphilosophie ("a German Romantic philosophy that sought metaphysical correspondences and interconnections within the world of living things1"). Agassiz earned a Ph.D. from the University of Erlangen in 1829 and a M.D. from the University of Münich in 1830. The next autumn, he went to Paris to study comparative anatomy with Georges Cuvier. His work on fossil fish impressed Cuvier, who helped the younger scientist by sharing his own notes. Cuvier died in April of 1832, but Agassiz continued to defend and promote Cuvier's theories of geological catastrophism and animal classification for the rest of his life.

Agassiz published his studies of fish in the huge volume Poissons fossiles for which he became known as the founder of paleoichthyology. Afterwards, he continued his researches as a professor at the Lyceum of Neuchatel, Switzerland. He was supported by both the King of Prussia and Alexander von Humboldt. Over the next thirteen years, Agassiz worked on various projects. He began to study Swiss glaciers in 1836 and later became known as the "Father of Glaciology". In 1840, he published his theory that Ice Ages in prehistory were caused by global climatic changes and these Ice Ages provided the catastrophic conditions which produced new forms of animal life in Etude sur les glaciers. A later work, Système glaciare, published in 1847, offered further arguments for this theory.

In 1846, Agassiz came to the United States, leaving his wife and children behind. After some time spent touring various parts of the country, he accepted a professorship at Harvard in 1848. Here, he continued his many researches and also became a vocal and successful advocate for American science. He began by organizing and finding funding for a Museum of Comparative Zoology at Harvard which opened in 1860. He campaigned ceaselessly against Darwin's theory of evolution, even to the point of alienating some of his students. Basically, evolutionary theory violated his conviction that there must be a Divine Plan in operation, with a Divine Being in control of it.

In the spring of 1850, Agassiz married Elizabeth C. Cady of Boston. His first wife had died in Baden two years earlier. Elizabeth became a mother to the children from the first marriage as well as working as a laboratory assistant for Agassiz.

Agassiz was a founding member of the National Academy of Sciences in 1863 and was involved in the founding of the American Association for the Advancement of Science. He served as a regent of the Smithsonian Institution. In 1865-1866, Agassiz lead the Thayer expedition to Brazil, where he collected many specimens of fish and unsuccessfully sought signs of glacial activity. Just before his death, Agassiz established the short-lived Anderson School of Natural History at Penikese Island, Massachusetts. He died December 14, 1873 and was buried at Mount Auburn Cemetery in Cambridge, Massachusetts. A big chunk of granite, taken from near his home in Switzerland, marks the grave.

Notes:
1. http://www.ucmp.berkeley.edu/history/agassiz.html
other information from:
http://www.nceas.ucsb.edu/~alroy/lefa/LAgassiz.html
http://research.amnh.org/ichthyology/neoich/collectors/agassiz.html