In 1859, Charles Darwin published On the Origin of Species, a book about the evolution of non-human animals by natural selection. In its wake, a political idea arose — eugenics. Reading Darwin's book, Sir Francis Galton proposed that humans should be bred to give more "suitable" characteristics a "better chance of prevailing." Today, producer Rebecca Ramirez talks to Adam Rutherford about his new book, Control: The Dark History and Troubling Present of Eugenics, which traces the inextricable link between political ideology and science, and the enduring shadow of eugenics.

This episode was produced and edited by Rebecca Ramirez and Gisele Grayson with help from Berly McCoy. Abē Levine checked the facts. The audio engineer was Maggie Luthar.