Clodd was an early follower of the work of Charles Darwin and had personal acquaintance with Thomas Huxley and Herbert Spencer. He wrote biographies of all three men, and worked to popularise evolution through books like The Childhood of the World and The Story of Creation: A Plain Account of Evolution.
Clodd was an agnostic and wrote that the Genesis creation narrative of the Bible is similar to other religious myths and should not be read as a literal account. He wrote many popular books on evolutionary science. He wrote a biography of Thomas Henry Huxley and was a lecturer and popularizer of anthropology and evolution.
eBook Occultism - Two Lectures Delivered in the Royal Institution on May 17 and 24, 1921