Evolution Day is a celebration to commemorate the anniversary of the initial publication of On the Origin of Species by Charles Darwin on 24 November 1859. Such celebrations have been held for over a century, but the specific term “Evolution Day” for the anniversary appears to be a neologism which was coined prior to 1997. By highlighting Darwin’s contributions to science, the day’s events are used to educate about evolutionary biology. It is similar to the better-known Darwin Day, held on the anniversary of his birth (12 February 1809). It is unrelated to the secularization campaign by the Giordano Bruno Foundation to have the German public holiday of Ascension Day renamed to “Evolutionstag” (Evolution Day).