Trench naturalist and formulator of a distinctive theory of organic evolution. Lamarck was born in the Picardy region of Prance to a noble family of somewhat declining fortunes. Originally slated for a religious career, Lamarck’s education began in a Jesuit school where he studied ancient languages, logic, mathematics, and scholastic thought. After his father died, however, Lamarck turned away from the religious life and joined the army. Eventually, he distinguished himself for bravery during the Seven Years’ War and was promoted to the officer’s rank, which afforded him enough leisure time to study music and botany. After an injury mustered him out of the military, Lamarck went to Paris, where he embarked on the scientific career that would make him famous.
In Paris Lamarck began his career as an associate of the famous naturalists Bernard de Jussieu and Georges-Louis Buffon. Initially interested in plants, Lamarck worked as a collector and classifier at the royal botanical garden. In 1789, he produced his first major scientific work, Flore frangaise, which was well received and prompted his election to the prestigious Academy of Sciences. In the midst of the French Revolution, he helped organize the Natural History Museum (Musee d’histoire naturelle). Lamarck focused his studies on invertebrate zoology and cultivated side interests in meteorology, hydrogeology, fossils, and conchology. His most important works were produced between 1800 and 1822, including Zoological Philosophy (1809) and The Natural History of Invertebrates (1815-22). In them Lamarck outlined a systematic theory of nature that included his evolutionary theories. These stressed the inheritance of acquired characteristics as a mechanism of organic change. The merits of the latter, dubbed Lamarckianism, would be debated by biologists and philosophers well into the 20th century.