On the Origin of Species — Darwin (1859)

On the Origin of Species delivers the most consequential scientific argument ever published: a coherent, evidence-based account of life's diversity that requires no supernatural explanation. Darwin’s theory of natural selection transformed biology, anthropology, psychology, economics, philosophy, and theology, and Richard Dawkins has called it "the most important book ever written." Over 165 years of subsequent evidence — including 99% of fossil transitions documented — have only strengthened its core claims. It fundamentally outperforms #2 in its ability to catalyze entire fields of inquiry, from evolutionary psychology to phylogenetic systematics.