Darwin changed late-19th-century American literature less by supplying plots than by changing its model of human nature: people could be portrayed as biological organisms shaped by heredity, environment, chance, and competition rather than as wholly free moral agents. His influence helped drive the transition from realism toward literary naturalism.nlm.nih+1
After On the Origin of Species (1859), evolution by natural selection challenged the assumption that life reflected a fixed, divinely ordered hierarchy. American writers could consequently depict nature as indifferent and unstable, and human life as continuous with animal life rather than separate from it.nlm.nih+1
The effect was neither immediate nor uniform. Recent scholarship argues that Darwin influenced some U.S. writers soon after publication—Henry David Thoreau’s scientific attention to geological and natural processes is a notable early case—although the strongest, most visible literary impact came in the 1890s.publicbooks+1
American naturalism converted evolutionary ideas into a literary method. Its writers emphasized causal explanation: inherited disposition, poverty, urban settings, labor conditions, sexuality, accident, and social pressure constrain a character’s choices.umsystem.pressbooks+1
Stephen Crane, Frank Norris, Theodore Dreiser, Jack London, and Edith Wharton are commonly associated with the broadly Darwinian turn-of-the-century naturalist sensibility. Their works favored gritty social observation and characters exposed to forces greater than individual will.nlm.nih
For example, Crane’s fiction often makes combat, poverty, or social pressure test a person’s fragile self-image; Norris and Dreiser investigate how economic and urban systems bear on desire and action; London uses wilderness and animal life to dramatize survival and adaptation. These writers did not merely “apply” biology—they used Darwinian concepts to question older ideas of autonomy, progress, and moral certainty.nlm.nih+1
“Darwinism” in literature often blended Darwin’s science with Émile Zola’s naturalist aesthetics, Social Darwinism, eugenics, racial ideology, and popular notions of “survival of the fittest.” Those are not interchangeable with Darwin’s evolutionary theory, and Jack London’s racial thinking illustrates how literary appropriations of Darwin could become entangled with damaging pseudoscientific claims.nlm.nih
Thus, Darwin’s central literary legacy was formal and philosophical: American writers increasingly made fiction a kind of social and environmental investigation, exposing how much human conduct might arise from conditions people neither chose nor controlled.nlm.nih+1