Lamarck, Histoire naturelle
Published before Darwin’s theory, this diagram summarized, in part, how French naturalist J. B. Lamarck understood evolution. Lamarck argued that animals strove to adapt to the needs of their environments, and their purposeful striving caused changes that ultimately made them more complex in form (a process shown here in two parallel columns). Darwin’s theory of natural selection countered Lamarck’s argument, which had been one of the most accepted ideas about evolution in the early 19th century.
Jean-Baptiste Lamarck (1744–1829). Histoire naturelle des animaux sans vertèbres.... Vol. 1 of 4. Paris: Verdière, 1815.