The concept of evolution first emerged in the early nineteenth century. Up until that time, the post-classical Western world had generally regarded the account of creation provided in the Biblical book of Genesis as literal fact. Thus, it was held that the world had been created relatively recently, that every species was created separately and distinctly, and that these species had remained unchanged over the centuries.

As the eighteenth-century scientific community began attempting to classify plants and animals systematically, however, the immense diversity and interrelatedness of living things cast doubt on this traditional model. The plant and animal fossils sought out by excavators were particularly at issue, since they implied that the history of earth extended back much further than previously thought, and that life developed only gradually and unevenly from simple to advanced organisms.

In 1809, the French botanist Jean Baptiste de Lamarck made an important...