FILE - In this undated file photo, British scientist Charles Robert Darwin, founder of the theory for the evolution of life is seen at an unknown location. An auction house said it is selling a rare first edition of Charles Darwin's "On the Origin of Species" found in a family's guest lavatory in southern England.
Credit: AP

Christie's auction house said the book - one of around 1,250 copies first printed in 1859 - had been on a toilet bookshelf at a family's home in Oxford.

The book will be auctioned tomorrow, the 150th anniversary of the publication of the famous work. Christie's said the book is likely to sell for 60,000 pounds ($99,000).

Darwin's The Origin of Species outlined his theory of natural selection, the foundation for the modern understanding of evolution.

Celebrations around the world this year have marked the 200th anniversary of Darwin's birth.