The French naturalist Jean Baptiste Pierre Antoine de Monet, Chevalier de Lamarck (1744-1829), is best known for his theory of organic evolution and his work on invertebrate animals.

Jean de Monet, Chevalier de Lamarck, was born Aug. 1, 1744, at Bazentin-le-Petit in Picardy. He studied for the priesthood, but on the death of his father in 1760 he joined the French army. When his military career ended because of illness in 1768, he went to Paris, where he began to study medicine. He also became interested in meteorology, chemistry, and botany.

Jardin des Plantes

Lamarck's scientific reputation was established with the publication of his Flore française (1778; French Flora), in which he combined the best of two competing systems of plant classification. This work brought him to the attention of the French naturalist the Comte de Buffon, who helped gain Lamarck's admission to the French Academy of Sciences in 1779. Buffon also...