Candolle , Augustin Pyrame de

(1778–1841) Swiss botanist

Candolle, who was born in Geneva, Switzerland, studied medicine for two years at the academy there before moving to Paris in 1796 to study both medicine and natural sciences. In Paris he met many distinguished naturalists, including Georges Cuvier and Jean Baptiste Lamarck, and quickly established his own reputation through the publication of many outstanding monographs on plants. He received his MD from the University of Paris in 1804 and, at the request of the French government, made a botanical and agricultural survey of France between 1806 and 1812.

In 1813 he published his famous Théorie élémentaire de la botanique (Elementary Theory of Botany), in which he introduced the term ‘taxonomy’ to mean classification. This work was based on the natural classificatory systems of Cuvier and Antoine Jussieu, and in it Candolle maintained that relationships between plants could be established through similarities in the plan of symmetry of their sexual parts. He realized that the symmetry could be disguised by fusion, degeneration, or loss of sexual organs, making structures with a common ancestry appear different. Candolle thus formulated the idea of homologous parts – a concept that lends much weight to the theory of evolution, but surprisingly he continued to believe in the immutability of species. Candolle's classification replaced that of Linnaeus and was used widely until George Bentham and Joseph Hooker produced their improved system 50 years later.

Candolle also made important contributions to plant geography, realizing that the distribution of vegetation can be profoundly influenced by soil type. The relationships he described between plants and soil were backed up by personal observations from his travels in Brazil, East India, and North China.

From 1808 to 1816 Candolle was professor of botany at Montpelier University, after which he returned to Geneva to take the chair of natural history at the Academy. On his arrival in Geneva he completely reorganized the gardens. Between 1824 and 1839 he published the first seven volumes of his hugeProdromus Systematis Naturalis Regni Vegetabilis (Guide to Natural Classification for the Plant Kingdom), an encyclopedia of the plant kingdom. His son, Alphonse de Candolle, saw to the publication of the remaining ten volumes after his father's death and also carried on many of his father's other schemes.