With the publication of The Origin of Species and The Descent of Man, Charles Darwin not only sparked a revolution in science, but also radically changed the way millions of people thought about themselves, their societies and their values. The evolutionary science he gave birth to acquired a political dimension from the outset, and one with a deeply troubling and ongoing impact on the world in which we live.

The Political Gene examines how scientists and politicians have sought to use Darwin's ideas to solve social problems, or to bolster political ideologies. Social Darwinism, eugenics and scientific racialism - whose adherents have all claimed Charles Darwin as their inspiration - became associated with some of the darkest episodes in our recent past. Dennis Sewell follows the thread of theory and the historical footprints left by a myriad cast of key characters to tell an often shocking and sometimes heartbreaking story. Sewell's narrative shows us what drove people to put a black man on display in a zoo, forcibly sterilize a pair of innocent teenage sisters, lock up a British girl for eighteen years for a petty theft, murder disabled people in Nazi Germany, and slam shut America's 'Golden Door'.

Poverty and welfare, race and immigration, education, sexual equality and human rights are just some of the public policy areas to have felt the effects of Darwinian thought. Today, rapid advances in genetic and evolutionary science are once again placing Darwin's theories at the centre of some of the most bitterly contested cultural and political controversies. In the future, as the stakes for humanity are raised yet higher, the gene is set to become more political than ever before.