England’s famed auction house Christie’s has managed to get an original copy of Charles Darwin’s On the Origin of Species, the book that details the scientist’s theory of evolution. The book, first printed in 1859, was found on a toilet book shelf in a family home in southern England.

Insert your own evolutionist theory crap joke here.

The book, one of only 1,250 first editions printed, will be sold on Tuesday to celebrate the 150th anniversary of its first publication. Christie’s estimates the tome could bring as much as $99,000 USD.