Do we not therefore perceive that by the action of the laws of organization . . . nature has in favorable times, places, and climates multiplied her first germs of animality, given place to developments of their organizations, . . . and increased and diversified their organs? Then. . . aided by much time and by a slow but constant diversity of circumstances, she has gradually brought about in this respect the state of things which we now observe. How grand is this consideration, and especially how remote is it from all that is generally thought on this subject!
— Text of a lecture given by Lamarck at the Musée National d’Histoire Naturelle, Paris, May 1803Jean-Baptiste Lamarck was born in the village of Bazentin-le-Petit in the north of France. Charles Darwin, Charles Lyell, Ernst Haeckel, and other early evolutionists acknowledged him as a great zoologist and as having helped establish the fact of evolution. Charles Darwin wrote in 1861 (The Origin of Species 3d ed., p. xiii):
Lamarck was the first man whose conclusions on the subject excited much attention. This justly celebrated naturalist first published his views in 1801. . . he first did the eminent service of arousing attention to the probability of all changes in the organic, as well as in the inorganic world, being the result of law, and not of miraculous interposition.
Georges-Louis Leclerc, Comte de Buffon, one of the top French scientists of the day, mentored Lamarck and helped him gain membership to the French Academy of Sciences in 1779 and a commission as a Royal Botanist in 1781. Lamarck was appointed curator and professor of invertebrate zoology at the Muséum National d’Histoire Naturelle in 1793.
Lamarck began as an essentialist who believed species were unchanging; however, after working on the mollusks of the Paris Basin, he grew convinced that transmutation (that is, evolution) of a species occurred over time. He became one of the first to use the term biology in its modern sense in his book Hydrogéologie, published in 1802. Lamarck’s book, Philosophie Zoologique (Zoological Philosophy), published in 1809 most clearly states his theories of evolution. Throughout his life, Lamarck criticized palaeontologist Georges Cuvier’s anti-evolutionary stance. He died penniless in Paris on December 28, 1829.