On this day in 1859, Charles Darwin's "On the Origin of Species by Means of Natural Selection" was published. Above is the only illustration from the original edition: a lithographic diagram by William West, which demonstrates how the degree of similarities between a number of varieties and species is explained by descent from common ancestors. . . . . . . . . . #darwin #charlesdarwin #evolution #science #onthisday #otd #today #history #sciencehistory #todayinhistory #sciencegoals #goals #evolve #humanevolution #family #genes #dna #diagram #originofspecies #species #life #earth #nature #illustration