Discovery BBC World Service

Who should be prevented from having children? And who gets to decide? Across 20th century America, there was a battle to control birth - a battle which rages on to this day.

In 1907, the state of Indiana passed the first sterilisation law in the world. Government-run institutions were granted the power to sterilise those deemed degenerate - often against their will.

In the same period, women are becoming more educated, empowered and sexually liberated. In the Roaring Twenties, the flappers start dancing the Charleston and women win the right to vote.

But contraception is still illegal and utterly taboo. The pioneering campaigner Margaret Sanger, begins her decades long activism to secure women access to birth control - the only way, she argues, women can be truly free.

In the final part of the episode, sterilisation survivor and campaigner Elaine Riddick shares her painful but remarkable story.

Contributors: Professor Alexandra Minna Stern from the UCLA Institue of Society and Genetics, Professor Wendy Kline from Purdue Univerity, Elaine and Tony Riddick from the Rebecca Project for Justice

Featuring the voice of Joanna Monro

(Photo: Elaine Riddick was sterilised without her consent, when she was 14, in North Carolina. Credit: Tami Chappell/The Washington Post/Getty Images)

"You will not replace us" was the battle cry of white supremacists at a rally in Charlottesville in 2017. They were expressing an old fear - the idea that immigrants and people of colour will out-breed and replace the dominant white 'race'. Exactly the same idea suffused American culture in the first decades of the 1900s, as millions of immigrants arrived at Ellis island from southern and eastern Europe.

The 'old-stock' Americans - the white elite who ruled industry and government - latched on to replacement theory and the eugenic idea of 'race suicide'. It's all there in The Great Gatsby - F.Scott Fitzgerald's novel set in 1922 - which takes us into the world of the super-rich, their parties and their politics.

Amidst this febrile period of cultural and economic transformation, the Eugenics Record Office is established. Led by Charles Davenport and Harry Laughlin, it becomes a headquarters for the scientific and political advancement of eugenics.

By 1924, the eugenically informed anti-immigrant movement has triumphed - America shut its doors with the Johnson-Reed Act, and the flow of immigrants is almost completely stopped.

Contributors: Dr Thomas Leonard, Professor Sarah Churchwell, Professor Joe Cain

Presenter: Adam Rutherford
Producer: IIan Goodman

(Photo: Immigrants arriving in Ellis Island, New York, 27 May 1920. Credit: Getty Images)

Clips: BBC News, coverage of Charlottesville protests, 2017 / CNN, coverage of buffalo shooter, 2022 / MSNBC, coverage of buffalo shooter, 2022 / Edison, Orange, N.J, 1916, Don't bite the hand that's feeding you, Jimmie Morgan, Walter Van Brunt, Thomas Hoier / BBC Radio 4 Great Gatsby: Author, F Scott Fitzgerald Director: Gaynor Macfarlane, Dramatised by Robert Forrest.

We follow the story of eugenics from its origins in the middle-class salons of Victorian Britain, through the Fitter Family competitions and sterilisation laws of Gilded Age USA, to the full genocidal horrors of Nazi Germany.

Eugenics is born in Victorian Britain, christened by the eccentric gentleman-scientist Sir Francis Galton. It’s a movement to breed better humans, fusing new biological ideas with the politics of empire, and the inflexible snobbery of the middle-classes.

The movement swiftly gains momentum - taken up by scientists, social reformers, and even novelists as a moral and political quest to address urgent social problems. By encouraging the right people to have babies, eugenicists believed we could breed ourselves to a brighter future; a future free from disease, disability, crime, even poverty. What, its proponents wondered, could be more noble?

The story culminates in the First International Eugenics Congress of 1912, where a delegation of eminent public figures from around the world gather in South Kensington to advocate and develop the science – and ideology – of better breeding. Among them Winston Churchill, Arthur Balfour, the Dean of St Pauls, Charles Darwin's son, American professors and the ambassadors from Norway, Greece, and France.

But amidst the sweeping utopian rhetoric, the darker implications of eugenic ideas emerge: what of those deemed 'unfit'? What should happen to them?

Contributors: Professor Joe Cain, Daniel Maier, Professor Philippa Levine, Professor Angelique Richardson

Featuring the voices of David Hounslow, Joanna Monro and Hughie O'Donnell

(Photo: Francis Galton (1822-1911), British man of science born in Sparkbrook (England). Ca. 1890. Credit: adoc-photos/Corbis/Getty Images)

Hiding in the shadows across the American continents lives a big cat with many names. From puma to mountain lion to panther to cougar, this animal is carnivorous, cunning and uses stealth to silently ambush its prey. Its elusiveness and brutal attacking style has earnt it the reputation of a cold-hearted killer. But behind this façade, hidden camera footage has revealed the cougar is all about caring for their family. And its silent whispering amongst the trees could actually be saving human lives. Adam Hart and guests uncover the mysteries of the ‘ghost of the forest’ and break its merciless stereotype.

Dr Laura Prugh, associate Professor of Quantitative Wildlife Sciences at the University of Washington, and Dr Mark Elbroch, ecologist and director of the Panthera programme in Washington USA.

Why do wasps exist? While many see them as unfriendly bees who sting out of spite, their aggression could be interpreted as a fierce form of family protection. They are hugely understudied and even more underappreciated, with hundreds of thousands of different species carrying out jobs in our ecosystems. Some live together in nests whereas others hunt solo, paralysing prey with antibiotic-laden venom. In abundance, they can destroy environments - outcompeting most creatures and taking resource for themselves - but could we harness their predatory powers to take on pest control? Adam Hart and guests are a-buzz about this much-maligned insect and explore why we should be giving them more credit.

Professor Seirian Sumner, behavioural ecologist at University College London, and Dr Jenny Jandt, ecologist at University of Otago, New Zealand.

As a great African predator and a hot-spot on safari, it is hard to believe that only last century, the African wild dog was considered vermin. It's beautiful coat of painted strokes makes it undeniably distinctive. Yet out in the field, this animal is hard to find. Yes, it camouflages easily against the landscape, but years of persecution, bounties and unintentional trappings means it's now one of the most endangered mammals on the planet. Revelations about its reliance on the pack for protection, predation and parenting means every dog matters in its bid for survival. So how can we further stop numbers dwindling? Adam Hart and guests investigate the tools and tales of the magnificent painted wolf.

Dr Dani Rabaiotti, zoologist at the Zoological Society of London, and David Kuvawoga and Jealous Mpofu, conservationists at Painted Dog Conservation in Zimbabwe.